Utah Teens Invent Better Air Conditioner

Carl Youngblood writes "Two recent Utah high school graduates won the first-ever Ricoh Sustainable Development Award for inventing a better car air conditioner based on the Peltier effect. The peltier chips used in the device are more energy-efficient, last between 20 and 30 years, are solid-state, and don't harm the environment with ozone-depleting freon like today's car air conditioners."

Comments

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[GoogolPlexPlex]

I wish they had built a better server.

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[softends]

It looks like Mirrodot didn't even get to it soon enough. The Peltier link works, though.

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[pcmanjon]

Ahh, I "read the fucking article" and now I understand. The main article makes you think a couple of chips save the day, and makes A/C's last longer. They do, in a way, but the article on ./ here should have quoted the real article, instead of trying to paraphrase.

"Today, the young inventors say, U.S. drivers use about 7.9 billion gallons of fuel each year to run their air-conditioners, which draw power from the engine. By adopting their contraption - which taps into the electrical system, using fans to blow hot air through five Peltier chips and then releasing cold air - they say the country stands to save 3.9 billion gallons of fuel annually, or about $10 billion based on current gas prices."

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[HeroreV]

It doesn't say 20 to 30 years longer, it just says that the peltier chips "last between 20 and 30 years". I have no idea why you just randomly inserted a word, but that's exactly what you've done.

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[Jumperalex]

Wel I can't sak you if you even RTFM'ed since I haven't either (damn /.) but I can ask if you even RTFS (read the f%ck1ng submission)?

They are mention the use of peltiers. Those are SOLID STATE heat pumps (for simplicity sake). that means no regrigerant (since Freon is a brand name) and no moving parts other than the fans on the hot and cold sides and the extra large alternator to power it.

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[kfx]

This article sounds like its stretching the truth. How can a couple of chips make an air conditioner last 20 to 30 years longer, and make it not use Freon (R12)

A Peltier device, when supplied electricity, transfers heat from one surface to the other. As such, there is no need for coolant, compressors, or any of that. They are solid state devices, and as such *should* last longer than anything with moving parts.

All you really need to build an A/C yourself is a few peltiers, a couple of fans, and some heatsinks to improve heat conduction to/from the peltiers.

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[NoImNotNineVolt]

The chip replaces the entire refrigerant-based cooling system. Including the compressor and the refrigerant. The peltier effect results in one side of the chip becoming cold when a voltage is applied. No refrigerant, no compressor. Just a solid state device, and cold.

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[Anonymous Coward]

WHY ON GOD'S GREEN EARTH IS THE PARENT MODDED INSIGHTFUL?

Ok, get this straight... from the article and what I know of the peltier effect (yes, I'd like a better primary source concerning the structure of the students' system given GM's naysaying), this is only a modification of an air conditioner system in the sense that it still has an internal loop for conditioned air cooled by a heat exchanger/evaporator (for lack of a better description of the peltier equipped analogue) -- the system no longer has a compressor, condenser, and coolant loop.

Instead, the peltier drives one side of the heat exchanger/evaporator to cool the conditioned air loop, and SIMULTANEOUSLY pumps the absorbed thermal energy and the peltier waste energy to the other side of the heat exchanger to dump the heat into a waste air stream.

I.E. - no coolant liquid (water, ammonia, R12, or R134a) and no inherent moving parts in the core cooling system (compressor), at the price of significantly higher electrical energy demands (the A/C system is mechanically driven and does not require a mechanical/electrical conversion step).

THIS IS NOT A CASE OF "PLUG IN THE MAGIC CHIP". It's the difference between installing a peltier CPU cooler and one of those phase changing multi hundred dollar monstrosities.

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[dknj]

what kind of power savings can we expect with this design over a refrigerant based design. I only see an improvement of not using ozone depeleting materials.. I am skeptical to believe that one of these devices won't expect the same kind of power a compressor needed.

of course i've never really investigated peltier chips either

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[Shanep]

The main article makes you think a couple of chips save the day, and makes A/C's last longer.

It did not make me think that at all.

Has the headline changed since you wrote this?

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[Shanep]

It's genius really, but unfortunately companies are already considering buying their idea. I'd suggest they patent the idea and sell the patent rights of it -- instead of being stupid and selling such valuable idea in full to some company.

I would not call it genius. It is just an obvious application of something which is very interesting (Peltier's). So obvious I thought it up all by myself many years ago. I realise many patents are as ridiculous as this, but they offend me and should not be possible. I mean this is what peltiers are for! Move heat from one place to another. It is up to you, the person applying the peltier, as to what medium you want the heat moved from and to.

I was going to do this years ago to see if I could cool my small computer room (at home). I don't know how well their patent application will go when this is already done in portable refridgerators (A fan-heatsink-peltier-heatsink-fan sandwich. With the hot heatsink outside and the cold heatsink inside).

The genius is the peltier, not the crud bolted to it.

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[modecx]

Yeah, of course this contraption ain't gonna be anywhere close to the efficiency of a decent/good refrigeration system.. I'm no AC guru, but I understand that refrigeration systems can be very very efficient. 80% on the low end and 90+% on the high end. That's pretty astonishing in the mechanical world, where typical engines are less than half that efficient.

"Invent" is a pretty strong word when you can go and find those mini in-car /desktop "silent refrigerators" using peltier chips at Cost-Co for $100.. They're not at all efficient, but if the need scratches... Itch it.

If one determines that it takes 5kw to cool a space then that's what it takes. At that point, it dosen't matter except for efficiency and other factors (i.e. environmental concerns) what you use to move the heat, but that's the power you'll need to provide... Unless you're using magic or mutant powers or something.

In this car, we obey the laws of thermodynamics!

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[vijayiyer]

And the electrical system gets its energy from the alternator, which gets its energy from the engine. Conservation of energy is alive and well...

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[Charcharodon]

Don't see how it is going to "save" fuel since taping into the electrical system puts a load all the same on the engine. Instead of the AC/pump getting the load the Alternator does.

Of course it is possible that the Peltier chips are more efficient, but considering the ones found on most electric coolers are around 60watts each I doubt it, considering you'd need 10-20 of them to keep up with the heat (the summers in CA are tough).

The real advantage would be that they are simple and wouldn't need to be connected directly to the engine. So if 1-5 broke you might not even notice.

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[AaronLawrence]

Except for one tiny details: they are not. They are an order of magnitude LESS efficient at moving heat.

Let's not let facts get in the way of a good story though.

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[modecx]

Yeah, too bad it's only a fraction of the efficiency of common refrigeration systems, contrary to what the writeup/article says, or what the editors beleive.

Unless these kids invented some breakthrough in peltier chips, this will never, ever, be practical. If indeed they did invent semiconductors that will compete with what's in your car (since I can't read the article), they deserve some kudos, and oh, a Nobel Peace Prize.

You really think that hundreds of thousands of people more knoweldgable and experienced seeking a way to make their company's products better than everyone else's wouldn't have stumbled upon this idea long ago? Oh, I'm sure they did. And then they said "Back to the drawin' board, Cletus!".

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[Rei]

Yeah, this article sounds like "really, really bad misunderstanding of science".

The reason why the Peltier effect isn't used everywhere a heat pump is needed - and it's a really neat effect, mind you, as it has no moving parts, little to get corroded, is small and lightweight, etc - is that it's inefficient. We're talking god-awful inefficient until recently (~5%), and even now we're trying to stretch it to ~20% in the lab (no easy task).

As another poster mentioned, conventional refrigeration systems are quite efficient - at least, by themselves. Now, for a home refrigerator, it doesn't work out so nicely, because your power is being generated at 50% efficiency, transformed multiple times at a loss, suffers transmission losses on the way to your house, etc (that's why propane and even solar refrigeration systems are more efficient). But for a system like in a car, where the motor is directly running the compressor, it's going to be very efficient.

The Peltier chips - inefficient on their own - suffer from the inverse problem that the refrigerator suffers from! They need DC electrical power, but what the car engine produces is mechanical power! The car's alternator produces AC at a loss, which is rectified to DC, which then goes to the lossy Peltier chips. Assuming "ebay chips" are, say, 5% efficiency, we're looking at an overall system efficiency of 1-2%. Yeah, great way to save gas.

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[dbIII]

Of course it is possible that the Peltier chips are more efficient

Obviously the laws of physics are different in Utah - elsewhere the peltier effect was understood and applied decades ago. Heat pumps do it the easy way with a lot less energy than the peltier effect, which has to do it the hard way. It doesn't take a lot of energy to move a gas and expand it, which is why you get an order of magnitude more heat moved that way than with the peltier effect. It's interesting stuff (look up thermocouples too - they work on the same principle) but not what these people think it is.

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[modecx]

The other sad facet of this is that if they intend to run this off the typical 12v system in a car it's going to need 83 amps of 12v per 3400BTU/hour (1000 watts) they intend to move even at 100% efficiency, ignoring losses in the cable.

Gonna need some real Monster Cable(tm) to handle much of that! You know.. You should be worried when they start looking for cable in the kcmil range.

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[Hadlock]

I don't know if you've ever worked on a car, but if you know what you're doing, you can change an alternator in about 20 minutes, or get it replaced at the dealership for $150. It costs that much to have someone look at your A/C system, let alone work on it. The A/C system truly has no user serviceable parts.

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[Petersson]

One side gets hot, the other is cold.

But the temperature rise on the hot side is much higher that the temperature drop on the cold side.

Generally it is silly to use Peltiers for cooling; if you use the hot part for heating while the cold part pumps heat from the outside, you will get >100% heating efficiency (read: the hot part will generate more heat than all the energy you put into electric circuit).

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[ajs318]

Well, ozone-depleting refrigerants were banned nine years ago {Google for "Montreal Protocol" sometime}. Modern refrigerators and ACUs use non-ozone-damaging chemicals anyway, thanks to the same Greens who are now complaining about them as though they were still being used, and when they finally get a clue they will whinge about something else instead.

For me, the big thing with vehicle air conditioning is the way American car manufacturers had to design this incredibly complicated electromagnetic clutch thingy to transfer power from the engine to the compressor or not depending whether or not the coil is energised. European cars {except for those arse-shunting German monstrosities} simply drive the compressor with an electric motor and fit a bigger alternator.

I wouldn't expect Peltier effect {think solid-state heat pump} cooling to be much more efficient than a mechanical heat pump, since in both cases you have the Second Law working against you {in any energy transaction there will always be some heat on the output side}. In a mechanical heat pump you have friction in the compressor bearings and between the fluid and the pipes; in a solid-state one, you have resistive heating.

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[rogerzilla]

Except that car alternators are surprisingly efficient - up to 90%. In fact, if it wasn't for the power supply difficulties (a typical 4kW unit would draw 333A at 12V), electrically-powered car a/c would have a huge advantage - it doesn't need expensive servicing every 2 years because there are no shaft seals open to the outside, hence no refrigerant leakage.

Domestic fridges are the most reliable applicances in the home because they are built as a completely sealed unit.

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[damsa]

AC can be user serviced. But then there is a strong chance that you might die. Alternator's have a lower likelihood of death upon servicing.

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[Lumpy]

Those numbers are skewed. Today's cars use more gas at highway speeds if only one window is down compared to the air conditioning. Hell the econobox I bought to beat gas prices loses only 1mpg when the AC is on (based on using a tankfull of gas. Comparing a month of commuting in cooler weather with only fan and vents open compared to the tankfull used when the AC was on full blast non stop.)

Older cars had horribly inefficent AC systems, and larger vehicles that have the equilivant of a house sized AC system also have horribly inefficent AC systems.

One of the most efficent AC setups in current production vehicles is in the Honda Insight and Toyota Prius. using less than 72 watts of electricity to run the electric compressor and a synthetic compressor oil + newer coolant technology.

you can not get near the efficency of a phase change cooling system with peltiers.

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[crath]

But Google's cache does have a copy.

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[budgenator]

1,1,2,2-tetrafluoroethane R134 is still ozone depleting but not as bad as the old R12 stuff is. What I can't figure out is given the
1. equilibrium of the Halides in the upper atmosphere in destroying ozone, about 1:35 a BadThing(tm),
2. the tendency of the halides to concentrate over the poles, a GoodThing(tm),
3. the large number of balloons send up to study the "problem"
wouldn't it make more sense to just say, we don't know if it will help or not, but if your package doesn't have a chemical pack to sequester atmospheric halides in the upper atmosphere, we're not going to give you any grant money for your study period.

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[budgenator]

now that's interesting. I wonder how it compares to geo-thermal heat pump style heating units

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[BillyZ]

Those numbers are skewed. Today's cars use more gas at highway speeds if only one window is down compared to the air conditioning.

Completely false. This statement is a common urban legend, and nothing more.

Using your AC taps mechanical power from the engine. This requires you to use more gas to maintain the same speed. Opening your windows adds some wind resistance, but doesn't add the same amount of loss as engaging the AC compressor. (you should watch mythbusters sometime, its a great show!)

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[Digital Vomit]

Today's cars use more gas at highway speeds if only one window is down compared to the air conditioning.

Didn't the Mythbusters prove this one false (albeit in a somewaht flawed test)? The car with the open window ran significantly longer on the same amount of fuel.

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[afidel]

Mythbusters was stupid on that one. They used a vehicle with about the highest possible starting drag and a huge, inefficient A/C system. With modern cars the change in wind resistance is a MUCH higher %age change in overall efficiency then the small amount of power robbed by turning on the A/C. Heck almost half of the power loss from an A/C system happens whether you use it or not, the belt's already going over the compressors feed wheel.

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[numbski]

econobox?

Never heard of it. I know several people that have made or purchased hydrogen boosters, but seeing as you have to use distilled water instead of tap water (unless you like cleaning disgusting slime out of your hydrogen generator), it is a bit of a pain.

What are you using?

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[TheScorpion420]

However unlikely it sounds this would save gas. It takes a lot of engine power to run the compressor for the A/C. Don't you notice how your engine bogs down when you turn the A/C on? You have to apply more throttle when the A/C is on to produce the same amount of acceleration or hold a speed than when it isn't on, thus you burn more gas. However the alternator on a car takes significantly less of the engines power, most people when driving don't even notice when the alternator kicks on, so the system can be massively inefficient but still save on fuel simply because it is taking electrical power instead of mechanical power directly from the engine.

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[BillyZ]

Heck almost half of the power loss from an A/C system happens whether you use it or not, the belt's already going over the compressors feed wheel.

this again is false. The compressor belt certainly turns, but it is not engaged. The pully spins freely with hardly any resistance. Try this as an experiment. Turn off your AC, get driving on a straight stretch of road with no traffic (for your own safety) get to a constant speed (even set the cruise if you have it). Then turn on the AC. You will hear and feel (and see if you have a tachometer) a sudden dip in the power output of your engine. AC Compressors take a large amount of horsepower away from the engine. This has been my experience with many different cars over a number of years. I currently drive a 2004 car so I would have to say its AC system and engine are fairly "modern".

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[TheScorpion420]

EEEEEENNNNNNNNNNNNTTTTTTTTTTT!!!! Wrong The A/C compressor has this thing called a clutch that while the A/C is off the pulley spins freely with no load other than its own weight. When you turn on the air the clutch enguages and voila nice cold air.

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[nuxx]

Did you note that the also ran the vehicles at 45MPH?

Change the speed to typical highway speeds (70MPH here in Michigan) and I bet the story would change quite a bit. I know that my car (a standard smallish sedan) drags quite a bit when you open the windows at highway speeds. Windows up and AC on, the throttle doesn't have to be depressed nearly as far in order to maintain higher speeds.

I'd agree that at 45MPH and below the AC is less efficient, but start getting up to faster speeds where the turbulance caused by open windows creates a *lot* of drag and I think the difference will be pretty obvious.

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[rogerzilla]

But drawing more power from an alternator increases the back e.m.f. and the engine has to work harder - you don't get nowt for owt and if you were drawing power for a large a/c unit from an alternator you would feel it kick in, I promise.

Thinking about it more, the reason car a/c is belt-driven is probably because no-one makes an alternator that can handle the current to an electrically-driven compressor. Ideally you'd have TWO alternators, one running at 12V (or 14.4V, which is typical) and the other running at 400V to drive the a/c without using huge fat cables.

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[Chrispy1000000 the 2]

So your going to ttell me that to get the comfort of an AC on full blast you are going to roll down all your windows at 70mph at highway speeds? You must have one mother of an AC then....

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[ebh]

That's not too bad of a mechanical problem, but the real danger of higher voltages in the engine compartment is sparks.

Because of the huge demand for current in modern cars (when's the last time you saw a window crank?), the automakers are trying to move to a 42V electrical system, but they're having a hard time bringing down the costs of all those gas-tight connectors, not to mention devising safe procedures for jump-starts etc.

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[jazzkat]

Completely false. This statement is a common urban legend, and nothing more.

Completely true. While the A/C taps power from the engine, rolling down windows taps more power from the engine to overcome drag.

I have a 2001 Chrysler Sebring sedan with the 2.7 V6 and one of those nifty trip computers. I use synthetic oil. At 75mph, I get around 31MPG. With the A/C on, that drops to 29 MPG. With the A/C off and one window down, that drops to 26 MPG. (This is with the cruise control on - so no lead foot to take into account.)

Care to back up your assertion with some facts?

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[Lord Pillage]

This is very interesting as it seems to break the first law of thermodynamics.

But seriously, go read a 11th grade physics textbook and don't post about stuff you 'think' you know.

A link to get you started.

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[samkass]

I'm curious if a hybrid car changes this equation at all. In stop-and-go city driving, if you can recover up to half of the gas energy in the form of electricity, would it be more efficient to drive the peltier off the battery, or the A/C compressor off the engine?

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[TigerTime]

Care to back up your assertion with some facts?

He did referencing the "MythBusters" Episode. They had two trucks, the exact same model going around the track at 45 MPH. The one with the windows down went 30 miles farther at a 15% savings of gas.

Granted that savings could change with increased speed. However, I would imagine MOST people don't average 75MPH in or around the city.

Essentially, use common sense. If you're getting on the interstate, roll your windows up. Otherwise, roll them down.

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[ginbot462]

Most manufacturers wouldn't won't to present milage in a bad light. So, gas milage is probably always calculated with the least drag (windows up) and a/c off. So while I doubt they have to report milage with the top down, that would be interesting to know.

Second, convertibles on average will get worse gas milage. They are not as smooth and are heavier (to add support for since the frame doesn't wrap fully around).

but, no one buys a convertiable to save on gas. And if you bought a Geo convertiable, 'the hell's wrong with you?

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[silicon not in the v]

Using your AC taps mechanical power from the engine. This requires you to use more gas to maintain the same speed. Opening your windows adds some wind resistance, but doesn't add the same amount of loss as engaging the AC compressor. (you should watch mythbusters sometime, its a great show!)

I watched that episode of Mythbusters about the A/C vs. open windows debate, and their conclusion was that it was pretty close to even. Their test results could barely find a difference, but their testing methods were so horrible(as in not real life) that I found any conclusion they would come to worthless. The biggest aspect that screwed up their results was that the identical vehicles they were using were both huge SUVs with V-8 engines. Of course an A/C compressor isn't going to be much of a load(proportionally) on that powerful of an engine.

I have always had small 4-cylinder cars, and in them, when you turn on the A/C, it feels like the car just hit a construction barrel. It's pulling a much larger percentage of power from the engine than on those big SUVs. That large percentage of power would translate significantly to lost fuel efficiency.

The other aspect about the Mythbusters test that was messed up was that they were running them around a closed-in, banked racetrack. The handling limitations of the SUVs on that track forced them to keep their speed down to about 45mph. Those two factors--the low speed and the sheltered from the wind environment pretty much take the wind resistance factor out of the equation.

So, myth: The Mythbusters show proved something about the A/C vs. windows debate? BUSTED!

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[sirket]

That was one of the less intelligent bits of testing they have done on that show and some of their test rigs have been doozies. Let's list some of the problems:

1- When they tested the car at 55MPH using the computer it showed that using the AC was more efficient. Jamie wrote this off as "Yeah but the computer was measuring airflow and not fuel consumption." Modern engines use O2 sensors and closed feedback to maintain stoichiometry. As a result if you use less air the engine will inject less fuel to maintain stoichiometry or the appropriate air-fuel balance.

2- When they did the objective testing they drove at 45MPH and not the 70-80 commonly done on American highways (Don't claim people don't drive this fast- get on any highway in New Jersey, New York, Mass, or Maryland where I drive). Drag increases exponentially so this can make a _huge_ difference.

3- Instead of draining the fuel tank they siphoned it out instead. They could have missed the fuel in the sump on one car and gotten it on the other. As the difference in economy was only about 15 miles (less than a gallon of gas) it could have made the difference on it's own.

4- They used two different vehicles for the test- as the difference was so small then it could simply have been a result of engine differences, tire pressure differences, air cleaner performance differences, transmission slippage, etc.

-sirket

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[andywww]

Don't forget that the weight of a conventional airconditioning system- liquid working fluid and all, is greater than the peltier system that the students designed. I'd imagine a lot of the power savings coming from reduced weight increasing fuel economy.

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[twosmokes]

Try living somewhere hot. I can drive down the highway at 70 with all the windows and my sunroof open and still sweat.

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[Charcharodon]

I cut my original response in half. I was starting to bring up that fact as well. Having Peltier units installed would and have one go bad would reduce repairing your A/C unit to something akine to changing a light bulb. That and the fact that you would have quite a few of them installed would prevent a total loss of your cooling system should one fail.

After looking online at a few sites I did find some interesting peltier coolers that might do a good job, but you are still talking about 500-1500 watts to do the job.

Well duh not thinking too well this morning, just remembered that the trend of auto is going towards hybride which happen to have 5000-15000watt generators built in. Maybe they're going to be practical after all.

It would be interesting to have them installed in a vehicle with a roof covered in solar cells. They could left on to keep things from heating too much while you were gone. Due to there nature they could also be intergrated into places such as the floor or the roof where they wouldn't take up much in the way of space.

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[sam_van]

Feh. A/C is not that difficult. Swapped out the entire system in my pickup in a couple of hours and have recharged a number of systems over the years.

The perception, however, is that it is something mystical...however, it is, in the end, a pretty basic system.

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[Spark00]

RTFA. the whole contraption doesn't last 20 years. the chips do.

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[ChrisMaple]

A car air conditioner pulls at least 2 HP, and often as much as 5 HP. Most alternators provide much less. This implies that the Peltier devices are going to have a lot less power available to them, and aren't going to be able to perform as well.

Typical air conditioners run at efficiencies of 200%-300% or better, the Peltier devices I've used are about 50%. Unless these kids have done something really outstanding, the numbers just don't work out for this being an effective system.

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[ChrisMaple]

Throttle depression is not a good measure. Some cars open the throttle a little regardless of driver input whenever the compressor engages.

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[malfunct]

Notice that I said "in this application" meaning car air conditioning. If they weren't more efficient than the existing car air conditioning I don't see any way at all that we could save "3.9 billion gallons of fuel annually" as the article very clearly states.

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[iamhassi]

"Assuming "ebay chips" are, say, 5% efficiency, we're looking at an overall system efficiency of 1-2%. Yeah, great way to save gas."

exactly. A quick search of ebay turns up several $10 peltiers, sucking down 170 watts each. That's ~14 amps each (170w divide 12 volts). Another search of ebay shows that car alternators are usually 100 to 160 amps, with 160amps being "high output" and 100 being closer to the norm. That's 100 amps to run the entire car, from radio to headlights to... well, you get the idea, in addition to charging up the car battery. Some alternators go as low as

This little "invention" (which i use losely, since all they did is reinvent the wheel) "blows hot air through five Peltier chips". That's 5 Peltiers each pulling 14+ amps each, so u got 70 amps of the car's total 100 amp alternator powering the peltiers! So now you get to decide if you want headlights or A/C. Oh and don't forget you wont be able to start your car since these will drain your 600amp battery in no time, and with the alternator constantly powering the peltiers it sure wont be charging the battery. Everytime you turn on the headlights, radio and A/C at the same time you're sucking battery power. Carry jumper cables with you!

Obviously whoever judged the constest knows very little about peltiers.

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[Pionar]

Yeah, I noticed that stuff, too.

I usually drive mid-size six-cylinder sedans. I love my Camry. You usually can't tell the difference when the air kicks on.

However, on a recent trip to Vegas, we took a friend's brand-new 2005 Corolla (a four-cylinder). When the air kicked on, you could definitely notice a "kick" in the steering as (I suspect) the A/C jolted the serpentine belt. It wasn't as noticeable as when I drove an Escort in the early 90s (shut up!), but it was still there. And it definitely made a difference on fuel mileage.

When you have 4000 miles to drive, you get to conduct lots of mileage experiments.

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[robslimo]

Uh, he's correct. The hot side gains more heat than is removed from the cold side because of, wait for it...

inefficiency! The extra heat is from that 92% to 95% inefficiency of Peltier devices!

11 grade physics is still holding strong.

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[iamhassi]

oh!! I forgot to add, those amp numbers for the alternators are maximum amp, meaning high rpms put out those numbers. When you're just cruising town you wont even be putting out 100amps, so your car will die within minutes of driving with these peltiers running. Can you use weaker peltiers? Course you can! But they wont cool as well, there is no "magic peltier" that proves sub-zero temps while sucking only 1 amp or something.

In closing this is the most worthless invention ever.

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[notthe9]

The Peltier link works, though.

Because we are going to /. the wikimedia servers?

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[PeelBoy]

Uhm.. "which draw power from the engine." and their solution "which taps into the electrical system"

And where exactly does this electricity come from? The land of make-believe? No. The alternator produces it, which runs off the power of the car which in turn consumes gas so uhhh.. Tell me again how this saves gas?

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[Rei]

Yes. They're efficient - at generating A/C. You need DC for peltier chips.

Also, to you the person who responded to you: Peltier chips are lighter, but the increase in mass for the alternator (and engine, given the efficiency) would easily outweigh it.

Re:/.ed

[narsiman]

And a conversion project to modify all cars on US roads will will cost $85.3 billion dollars, resulting in employment opportunities to 2.5 million. In addition this would result in production changes to all car manufacturing process adding an additional cost of $8 billion. But this would result in adding an addition $115 billion dollars to the Peltier chip manufacturing and support industries.

Now if we can only find somebody to lobby . . .

Re:/.ed

[Lord Pillage]

(read: the hot part will generate more heat than all the energy you put into electric circuit).

It is possible for the 'hot' side to become hotter from this inefficiency, but it is still impossible to retrieve more energy from the system than is put into it.

Re:/.ed

[PeelBoy]

I didn't catch the entire episode, but I remember the conclusion being NOT to drive with your windows down.

Re:/.ed

[erveek]

They need DC electrical power, but what the car engine produces is mechanical power! The car's alternator produces AC at a loss, which is rectified to DC, which then goes to the lossy Peltier chips. Assuming "ebay chips" are, say, 5% efficiency, we're looking at an overall system efficiency of 1-2%. Yeah, great way to save gas.

This assumes the car uses gas.

Re:/.ed

[iamhassi]

"the trend of auto is going towards hybride which happen to have 5000-15000watt generators built in. Maybe they're going to be practical after all."

yeah, but that's to power the car, not a 850 watt A/C unit (170 watts each X 5)

"It would be interesting to have them installed in a vehicle with a roof covered in solar cells. They could left on to keep things from heating too much while you were gone."

yeah sure, cuz I could strap 850 watts worth of solar cells on my roof :rollseyes:
"A Siemens 610mm x 1321mm panel will produce 110W...weighs 25 pounds (11Kgs) and costs US$634 for 12V production".

So I just need $5000 worth of solar cells, not to mention a roof the size of half a basketball court, oh and dont forget the 200 lbs they'll weigh...

Re:/.ed

[bobcat7677]

I have a couple large electric fans for cooling the radiator on my Honda. For whatever reason some engineer thought it would be a good idea for both fans to come on at the same time when the radiator needed cooling. At idle having these fans comes on produces a very noticable drop in RPM and if I'm watching a volt meter you can see the system voltage drop to seriously low levels (it will kick one of my inverters into protect mode every time). That's on a 1.7L 135HP engine. Consider if you will that those fans are drawing (educated guess) ~10amps a piece (12V). Imagine adding an electrical load of another ~40amps(12V) to that in peltiers. Plus another 10amps at least of fans to blow the air around them. You would have to add another alternator to handle that much load (you could upgrade the existing one but an upgraded one able to handle that much load would be prohibitively expensive). And at that point you are basically just replaceing the load of the air conditioning pump with load of another alternator. Unless they somehow found a way to magically make the peltiers move just as much heat on less current then they normally operate on, I don't see how this would be any more efficient then conventional A/C...possibly less efficent. Almost everything is designed for or has been converted to freon alternatives now that don't hurt the ozone. So other then the no-moving-parts arguement I don't see a benefit.

Re:/.ed

[Bulldozer2003]

Mythbusters is horrible. Not even an inkling of the scientific method. Anyone that takes their results as truth without doing their own experiments is a fool.
They don't test in the right environments.
They don't test adjusting for all the variables.
But at least they're entertaining right?

Re:/.ed

[Tacky the Penguin]

I'd agree that at 45MPH and below the AC is less efficient, but start getting up to faster speeds where the turbulance caused by open windows creates a *lot* of drag and I think the difference will be pretty obvious.

Without turbulence, aerodynamic drag increases linearly with velocity. With turbulence, it increases with the square of the velocity.

Re:/.ed

[Artfldgr]

they also work in reverse... so you can use peltiers to generate electricity which is also a cooling effect.... now put them in opposition and use all the heat you want from the engine as its free... that in turn makes more elect for the peltiers that will cool the ambient air at the point were the people are.

Re:/.ed

[Obfuscant]

He did referencing the "MythBusters" Episode.

Mythbusters is entertainment, not science.

The main flaw in their "experiment" was that they used two different vehicles and did the run once. The difference between the two could have been entirely due to differences in the carburator setttings. They did nothing to rule that out.

Had they done the experiment ten times, swapping the "window open" and "AC on" between the two, I'd be more impressed with the results. Had they used real measurements (such as a fuel flow) I'd be convinced.

Re:/.ed

[robslimo]

er, you're right. he was going strong til that last bit (which I apparently didn't read the first time).

Re:/.ed

[PeelBoy]

It's not all bad.

Their methods are fine for most of the myths they bust.

Re:/.ed

[sirket]

Shooting a .50 calibur rifle at a pool and seeing a huge plume of water and a disintegrated bullet made one of the more recent episodes entirely worth watching :)

Re:/.ed

[mollymoo]

Yes. They're efficient - at generating A/C. You need DC for peltier chips.

Yeah, it's a pity you can't efficiently rectify AC into DC. Oh, wait...

Re:/.ed

[dknj]

you're missing the point. if it takes 1000 watts of energy to power a compressor and 1000 watts of energy to power the heatpump/chips, you still use the extra fuel to turn your alternator instead of your a/c compressor. no savings in fuel economy. that was my original question

Re:/.ed

[PitaBred]

Actually, mileage stickers are calculated via an EPA equation. That way you don't have manufacturers trying to game the system.
But since there are so many advances and differences in cars and so on, what you see on the sticker is rarely related to actual milage under real driving conditions.

Re:/.ed

[Rei]

Yeah, it's a pity that I had to go and say that you can't efficiently rectify AC into DC. Oh wait...

The problem is when you chain losses. The best small rectifiers will get you ~90% efficiency. Chain that with a good, new alternator (say, 80% for a new 42V at optimal engine speed - old alternators are often 50% or so, the best 14V alternator is about 72%, and higher speeds waste energy), and you're down to ~70% efficiency. Chain that with a 5% peltier efficiency and a 30% efficient engine, and you're down to 1% overall system efficency (take out the car's engine's efficiency from consideration, and you're at 3%).

Use an older alternator, and those numbers drop to 0.6% and 2%, respectively. Use a non-optimal engine speed, and again, the numbers fall.

Re:/.ed

[toddestan]

My 1988 Nissan (a boxy 4 door sedan with 4 cylinder engine) actually stated in the owner's manual that is was more efficient to run the A/C at highway speeds than it is to open the windows. Though I certainly wouldn't take the owner's manual of some car as the final word in the matter. Unfortunently, I never did actually get to test that out, because by the time I got the car the A/C had already gone kaput.

Re:/.ed

[toddestan]

Mythbusters is entertainment, not science.

And that's the reason I cringe just about everytime someone brings that show up here on slashdot. They've done some good episodes, but some seem to create more myths than they "bust".

Re:/.ed

[Andy Dodd]

Unfortunately, the article is 100% false in its claims that Peltiers are more efficient than phase change heat pumps. Peltiers are known for being INCREDIBLY inefficient.

Re:/.ed

[geoffspear]

Actually, no. My car's not a piece of crap, and has no noticable power drain when I turn on the A/C.

I did have a Subaru 10 years ago on which the effect was so bad that you could practically stop the car without the brakes by turning on the A/C, no no car I've driven more recently has had this problem.

Re:/.ed

[modecx]

Power is power, guy. If it takes 10 horsepower to cool your car, then it dosen't really matter what path it takes, except for the sake of efficiency... Simple as that. The power to generate the electricity still comes directly from the engines' crankshaft, whether you care to believe otherwise. There's no magical Electricity Elves in that alternator, or the belt that powers it--which is often the same belt (which is about 98% efficient if tightened correctly, FYI) that powers the compressor.

The fact is that a standard car alternator will probably never produce more than 1200 watts (100 Amps). That's A little over 1.5 horsepower. A car AC sytem is probably at least 18,000 BTU/hr, maybe almost double that for a big car/SUV. So now you know why your alternator drags on your engine about 1/15th that of your AC. Furthermore, alternators do not always run at 100% capacity. The largest loads on an average alternator is often the the rear window defroster and stereo system, followed by replenishing the battery from it's ignition duties--except for those jerks that decide a 2kW Thunder Pumper(tm) sound system is in order, then the stereo wins..

Peltiers would have to be 95% efficient just to make up the losses in the alternator enough for them to be practical. Aint' gonna happen this decade.

Re:/.ed

[silicon not in the v]

So driving at 40 mph on a track takes wind resistance out of it?? Were they in a vacumn? Driving at 45 MPH gives you 45 MPH or wind resistance, wind from the enviornment is not an important factor here, just the acutal speed the car was traveling

Maybe I was unclear in leaving the detail out of it, but as someone mentioned elsewhere in this thread, air resistance goes up exponentially with speed. At lower speeds like 45mph, other factors like engine power, tire rolling resistance, etc. are the dominating factors, and air resistance is extremely minor. At very high speeds, air resistance comes to be the dominant factor of a vehicle's resistance to movement. In fact, if you read a lot of car reviews, they will specify on the top speed whether it is limited by engine governor, engine capability, or wind resistance.

My comments about being in a sheltered environment are relevent because any "natural wind" in the environment except for a tailwind will also contribute to drag. So for real-world highway conditions at about 70mph out in the open, the wind drag will be more severe than their tests account for.

Re:/.ed

[JetTredmont]

Exactly. If your open window is generating enough drag to affect gas consumption to anywhere near the degree your AC does, then keeping cool is your least concern.

More important: wind burn, surprisingly hard crickets hitting soft human flesh at 70 miles per hour, and your map flying out the window.

At 70mph, if I have the window open, it is only a crack open. Additional drag is only marginally higher than that at 45mph or 25mph.

Re:/.ed

[tricorn]

The peltier effect IS a heat pump. I don't know where you get the idea that it doesn't take a lot of energy to compress the gas down in the first place (which you have to do to get it to release the heat). That energy can't be recovered when the gas expands after it has cooled down.

What I've always wondered is if you could do a more direct air-conditioning by compressing the air you want cooled, running it through cooling fins, then expanding the air and releasing it.

Re:/.ed

[TClevenger]

They also did pretty poor in their measuring and metering of the gasoline, and relied on the fuel tank pickup (which varies between vehicles, especially when driving in a circle.) If they had been smart, they would have used a separate measured tank instead of "take about 12 gallons out and drive it until it runs dry."

Re:/.ed

[dbIII]

I don't know where you get the idea that it doesn't take a lot of energy to compress the gas down in the first place (which you have to do to get it to release the heat)

I suggest you get hold of any first year university thermodynamics textbook - refridgeration is explained well in all of them.

One old and simple example is the kerosine refridgerator. In that case the compressor is a reservior of water, ammonia is the working fluid, and kerosine is used to provide flame to get some heat input to keep it all moving before the expansion nozzle.

compressing the air you want cooled, running it through cooling fins, then expanding the air and releasing it.

It's a lot easier to compress the working fluid/gas, run it through a cooling system (for example the exposed copper piping with a big surface area on the back of old refridgerators), then expand it. Gasses that we can do this to easily are the ones that are used as the working fluid - with air it's a lot of hard work to get the CO2 out so you don't get solids and then compress the nitrogen down to a liquid. It's far easier to cool something else and blow the air past it than to compress and expand nitrogen.

Re:/.ed

[JLF65]

Gas mileage isn't calculated by actually driving the car around. The car is placed on a machine that puts rollers under the drive wheels. The car is put in a certain gear and the engine run at a certain RPM to determine "city" and "highway" mileage. As the car never actually moves, wind resistance (among other things) never figures into the mileage.

Re:/.ed

[OhioJoe]

Just curious, but does the amount of electricity the peltier chips will need make a peltier chip AC unit in a car silly? I.e., if you are funneling that much electrical energy into the AC unit, why not keep the old AC unit and funnel that electrical energy into supplying a hybrid engine with energy? However, the ozone factor still is valid.

OJ

Re:/.ed

[coopex]

Oh wow, you took junior high physics too! That's nice, but Thermodynamics doesn't get taught, at least at UIUC, until sophomore standing.

First of all, for god's sake, if you're gonna use a physics link use some like Hyperphysics

Secondly, he's talking about heat pumps - so the first law of themodynamics would say that delta U = Q - W, and since the work is being done by the peltier to the system (car interior), it's negative, so you get the delta U = Q + W, where resistive heating would only get you delta U = W, hence > 100% heating efficiency.

Knee jerk reactions based on very limited phyiscs knowledge make you look both arrogant and stupid.

Re:/.ed

[Charcharodon]

There are a few companies that are selling thin film solar cells, they're printed on plastic or steel. Several are finally maturing enough to the point that they don't have to be the clasic red, blue, or black solar cell colors.

http://solarworld.com/PowerFilm.htm/

They aren't cheap, but the price is dropping quickly. The weight is more reasonable.

Make it so the "paint" of the car is the solar cell and throw in a hybrid that can take advantage of the extra juice. It'll give you a little more range and let you run things while you are parked or stopped without the engine kicking on. I can see something like that taking off once it hits the $1000 option mark for at least 1000watts.

Using them to run the A/C while your car is parked on the hot asphalt probably wont result in the bottle of soda you left behind being frozen, but maybe it'll stay cool enough that it wont explode and you wont get 3rd degree burns on your legs when you jump in to take off.

Re:/.ed

[Charcharodon]

Yep that was brough up many times. They have many advantages, but you are correct efficiency isn't one of them.

The boys concept of what is an acceptable A/C unit in Utah wouldn't work in say California or Arizona. It would simply be too low powered. Most people forget that the auto manufacturers put A/C units in cars that can survive out here in the Mojave even if they are selling them in Alaska. Of course by the very nature of a Peltier cooler you could just simply add more modules for more cooling and gain efficiencies by simply only installing and using what you need, vs a standard A/C unit which is pretty much all or nothing.

Cost scaleable
Size easily integrateable
No chemicals
No plumbing
Runs on electricity
can be made to generate electricity as well as cool/heat
long life
relatively inexpensive
very low tech, easy to work with

Re:/.ed

[FlyingRobin13]

Wouldn't it be much more efficent to just reflect the solar energy away from the car, rather than absorb it, convert it to electricity, run a heat pump, and fan... to pump the energy which wasn't absorbed by the solar array... out again. Much cheaper solution: a biiiig sheet of mylar; drape it over your car, blind all other motorists, and have a _clear_ road all the way to work!

Re:/.ed

[Grishnakh]

Weight really doesn't have that much effect on fuel economy. Subtracting 20 pounds of weight will have a negligible effect, and that's probably a generous effect. Notice how your fuel economy doesn't drastically drop when you bring along a 150-200lb passenger. The heaviest A/C system probably only adds 40-50 lbs. of weight.

Re:/.ed

[Grishnakh]

No, they don't. This fair was run in Phoenix by Intel, and IIRC was judged by Intel employees. They're not going to be experts any more than anyone that frequents /. Worse, they probably know very little about refrigeration systems, which is probably why they didn't immediately see how this "invention" is actually quite useless.

I'm no A/C expert either, but I am an engineer, and after reading through all the posts here, which quite clearly, using real numbers, illustrate why this invention is useless because of the poor efficiency of Peltiers, I'm convinced.

If someone ever improves Peltiers to where their efficiency is much better than that of a conventional refrigeration system, then maybe this would make some sense. But for now it looks pretty stupid.

Re:/.ed

[Grishnakh]

When it's 113 degrees outside, it doesn't matter how fast you go; wind from outside will never approach the comfort of A/C.

No more freon in cars

[ToadMan8]

Cars sold in the states haven't used Freon since the late 90's. That's why A/C sucks in cars now.

Re:No more freon in cars

[AKAImBatman]

I *still* think that Cryocoolers are the way to go. You can't tell me that a Stirling or Pulse Tube cryocooler would cost that much more to mass produce than a regular AC unit. Not to mention that the engine load would drop to an unnoticable amount in comparison to today's AC units. Even the EPA's own documents mention Stirling coolers as an acceptable solution! :-)

Re:No more freon in cars

[ciscoguy01]

Yeah, they use that fake freon.

If I'm gonna die from ozone depletion I want to at least be cool while I'm doing it.
Give me freon or give me death!

Re:No more freon in cars

[jimi the hippie]

All cars with A/C still use freon. They don't use R-12!! (which is the stuff that supposidely depletes the ozone, and has been illegal since about model year 1995, NOT the late '90s)

Freon != R-12

Re:No more freon in cars

[pongo000]

This should actually have been modded as "misinformed" (don't we wish...)

R134a A/C systems have evolved over the years. Granted, the early systems left a lot to be desired, but the output of the recent systems rival that of old R12 systems. R134a systems are very pressure-dependent, far more than R12, and must be precisely charged for maximum effectiveness.

It's hot here in Texas, at or above 100F in the summer, and both of my Chevy trucks (an '02 and an '03) blow frigid air.

Re:No more freon in cars

[akhomerun]

how do you know this much about CAR AIR CONDITIONERS?

i thought people on /. were just linux and computer geeks!

Re:No more freon in cars

[minus_273]

well that and the insane amounts they have to spend on workers salaries and benefits when compared to the rest of the world. There is no way they can compete. It's funny when you realize that becasue of the unions and their short sightedness, many of those jobs will disappear in the next decade or so.

Re:No more freon in cars

[Basehart]

I just wind all the windows down and don't drop below 120MPH.

Re:No more freon in cars

[Anonymous Coward]

R-134a is still considered a Freon. While it has a low ODP - ozone depletion potential, it is still considered a greenhouse gas so it is not complete innocious. Hydrocarbon blends are used for cooling systems all over the world but greatly discouraged in the US (propane, the major component, was $1.74 a gallon when I filled a tank last week) Can anybody say Profit?

Re:No more freon in cars

[JanneM]

well that and the insane amounts they have to spend on workers salaries and benefits when compared to the rest of the world.

Other companies around the world do pay for pensions and health care as well. Not by setting up their own insurance funds, but by paying higher salaries (to compensate for the higher income taxes on those salaries) and by paying sometimes quite high employer fees. The difference is really that in state-run system everybody shares the cost, while for the US carmakers they are stuck with the bill for a lot of workers all by themselves.

Re:No more freon in cars

[CurlyG]

You're delusional. You really thing the average German worker in the automotive industry gets lower salaries and fewer benefits than his equivalent in the US?

Try again.

Re:No more freon in cars

[EnronHaliburton2004]

I'll partially agree.

But European Car Makers are pretty competitive, and their unions are much stronger and demand greater benefits then American Unions.

And Japan has alot of socialized services, such as National Health Care. As a result, the Japanese corporations are able to remain much, much more competitive. Here in the States, the companies pay for the healthplan. I don't know any auto assemblers, but a typical healthplan for my professional friends costs $10,000-12,000 for 2-4 people. That's a ton!

Re:No more freon in cars

[deglr6328]

Sigh... I've always said that cryogenic liquids were the way to go. You CAN'T tell me that a 20L dewar of liquid air piped directly onto the driver's lap would cost much more than a regular AC unit! :)

Re:No more freon in cars

[ppanon]

Doesn't help if the temperature outside is over 100F; you just cook faster.

Re:No more freon in cars

[drsmithy]

well that and the insane amounts they have to spend on workers salaries and benefits when compared to the rest of the world.

You mean compared to countries like Germany and France ? (Well known everywhere as bastions of conservative capitalism and mercifully free of the unionised workplace).

Re:No more freon in cars

[majikenny]

nah, people here are just geeks in general. Thus mechanical engineers arent entirely out of the allowed crowd, just not the main group. now if he was in marketing or something, that'd be a little wierd. but engineers are just as geeky/nerdy as you crazy computer foklks.

Re:No more freon in cars

[AKAImBatman]

Errr... no. There are no cryo liquids in these coolers. They're used to make cryo liquids, although in much bigger form than you'd use in a car. A Stirling Engine is a reasonably simple device. You have two pistons, a regenerator, a hot surface, and a cold surface. Heat the hot surface, and you get energy as the heat is pumped to the cold side. Apply energy to drive the engine, and the cold side will pump all its heat to the hot side, making it that much colder. Damn efficient devices, they are.

I briefly discussed this topic recently when we were talking about keeping computers cool. The heat problem is becoming so critical that Intel is actually designing a Pulse Tube cooler for their microprocessors!

Re:No more freon in cars

[jonored]

Last I heard, the drag from having open windows smacks your fuel effeciency a lot more than having an AC unit, and doesn't keep you as cool...

Re:No more freon in cars

[Anonymous Luddite]

>> but a typical healthplan for my professional friends costs $10,000-12,000

According to my company, the non-cash benefits I receive cost them (and our customers ultimately) more than half my cash salary in addition (I do have an excellent benefit package though)

>> And Japan has alot of socialized services, such as National Health Care. As a result, the Japanese corporations are able to remain much, much more competitive

having company-run unions help the japanese corps *just* a little bit there too.

Re:No more freon in cars

[Trepalium]

Sure it does. The added wind cools you by evaporating sweat. The only time it doesn't work well is when the humidity levels are extremely high.

Re:No more freon in cars

[Breakfast Pants]

You would get dehydrated really fast. With temperatures above 98.6 wind feels good until you pass out from dehydration.

Re:No more freon in cars

[deglr6328]

I know what cryocoolers are. It was a JOKE :)

Re:No more freon in cars

[Slipped_Disk]

You. Are. Wrong.

The drag from rolling down your windows does not kill your fuel efficency as much as turning an AC compressor.

Don't believe me? Take your car to a track and run it until it stops - first with your windows down, then with the windows up and the AC on. See which runs longer.

Re:No more freon in cars

[dreadknought]

The EPA also approves about twelve refrigerants for use in automobiles. You know how many the automotive industry approves? two. R-12 and R-134a. You will never find a shop anywhere in the world that will charge your A/C with anything but R-12 or R-134a. Just because the EPA approves something for automotive use doesn't mean the industry will. Afterall, the EPA most likely aren't experts in the field of automotive airconditioning.

Re:No more freon in cars

[ForestGrump]

tried it before, and either way, it tops out at 120 mph...damn you governor!

Re:No more freon in cars

[mrchaotica]

They proved that false on Mythbusters a while back. Of course, wind resistance increases with the square of the speed, so the faster you go the closer you come to breaking even. Seeing as how they tested at 55 MPH (I think), if you're doing 70 or 80 the AC might be more efficient.

You're right that the AC keeps you cooler, though...

Re:No more freon in cars

[WhiteWolf666]

A/C sucks in cars now?

The A/C in my Lexus, my dad's Benz, and my sister's escalade all rock.

Instant on, instant cold, instant-blast-of-frigid air. Then, they get colder.

This is in the midwest, chicagoland area. So its *friggin* hot. Like 100F, or higher.

Re:No more freon in cars

[Rei]

That Mythbusters ep was so faulty. Why they decided to go on "which ran out of gas first, after doing guestimation on how much to fill and remove, with two separate vehicles and two separate drivers with one trial run", instead of the readings on how much fuel was actually being burned, is beyond me.

Re:No more freon in cars

[zippthorne]

contents of compressed gas air duster (office depot variety):
1,1,1,2-Tetrafluoroethane
(from quick google search)

contents of R134a recharge canister (avail at autozone and Kmart even)
1,1,1,2-Tetrafluoroethane
(from the label on the partially discharged canister I happen to have lying around)

There are more warnings on my can of "refrigerant" than on the "air duster" though. (and it has to be the same pressure too, whatever pressure brings the boiling point to room temp) One of those is that I am not supposed to discharge the car AC into the atmosphere: i'm supposed to take it to a garage which collects the refrigerant for proper disposal/storage/whatever.

side note: It's cheap, easy and fun to recharge the refrigerant in your car's AC. Unfortunately, most of the problems that can be solved by a quick recharge have an underlying cause that necesitates replacement of one or more componants anyway. This requires a complete bleed down and flush anyway, so you might as well take it in for service unless you feel like doing all of that yourself. (don't forget to add lubricant when you replace everything, the compressor will thank you)

Re:No more freon in cars

[zippthorne]

Mythbusters did not prove it false. They showed one case where it was false. I think they're fun to watch, but their "scientific method" leaves much to be desired. giving me things to bitch about, making them even more entertaining :)

In the episode of which you speak, they had two different cars and two different drivers and they only ran the course once. If they'd done several trials and switched drivers a couple fo times, and rotated the tires between cars after each run, then maybe they'd eliminate enough of the variables to make a statement of any confidence.

(a few pounds of underinflation on the tires on one car could've explained the discrepancy they saw) what about alignment, tire wear etc.?

Not only does the AC keep you cooler, but it also doesn't muss your hair.

Re:No more freon in cars

[jrockway]

It hasn't been over 100F in Chicago since July 30, 1999.

But it is hot out, I'll give you that :)

Re:No more freon in cars

[jizmonkey]

The difference is really that in state-run system everybody shares the cost, while for the US carmakers they are stuck with the bill for a lot of workers all by themselves.

More precisely, as I understand it, is that when an industry shrinks its domestic footprint (like the steel and auto industries), underfunded private pension and health plans are in huge trouble. It doesn't matter if there's "a lot of workers," because they're working and able to pay their own way (the benefits are just a form of compensation), it matters if there's a lot of retirees compared to the number of workers.

Re:No more freon in cars

[MemoryAid]

I generally don't like nitpicking, but since I do like thermodynamics...

• Temperatures above body temperature can still feel cool, as the wind will carry away the latent heat of vaporization of the sweat.
• Humidity is a big factor in this; lower is better for evaporative cooling.
• 98.6 is the average core body temperature. Average skin temperature will be lower.
• 98.6 is a fairly bogus number with respect to significant digits. It is just 40C converted to Fahrenheit, but even that number is plus or minus a degree or two for normal population distribution.

Good point about dehydration, though.

Re:No more freon in cars

[forty7]

Since you're picking nits anyway... :o)

98.6 is a fairly bogus number with respect to significant digits. It is just 40C converted to Fahrenheit, but even that number is plus or minus a degree or two for normal population distribution.

It's just 37C converted to Fahrenheit. 40C is 104F.

Re:No more freon in cars

[VectorSC]

Drive a 1994 Nissan Pickup truck some day, and say that again in relation to that particular model. We managed to get a 60 degree drop out of it. We let it run for 3 minutes when the outside temp was 96 degrees. The interior temp, with the A/C on high, was 36. And yes, it used R-134. :-)

Re:No more freon in cars

[DigiShaman]

No, A/C sucks because the major car manufacturers are too lame to figure out how to build good A/C without Freon. It's possible, they just won't do it.

American auto manufacturers especially. They fail to innovate, and are going down the tubes. Nobody to blame but themselves, really.

As long as it's American bashing going on, this WILL get moderated up.

Fact is, EnronHaliburtons post is a troll! And he knows jack shit about the auto industry or how A/C systems work in general. Had he done his homework, you would realize that the FACT is R134 is LESS efficient then R12. That's correct EnronHaliburton2004... you troll. Do your god damn homework. And no, I won't do it for you. Google it.

While were at it, AC systems have always blown less cool regardless of the auto manufacture. This isn't an American sucks issue. This is an R134 sucks "issue". I bet my Honda on that!

Re:No more freon in cars

[mboverload]

They did a special episode behind the scenes that shows they really DO do experiments over and over again. Lots of times. It would just be boring to put that in the episode.

Re:No more freon in cars

[ultranova]

You would get dehydrated really fast. With temperatures above 98.6 wind feels good until you pass out from dehydration.

Unless, of course, you do an amazing move and drink something. Hmm... Maybe I should patent this innovation. "A method of preventing dehydration in organic beings using dihydromoxide injections".

Re:No more freon in cars

[donscarletti]

I never thought I would ever see a single comment that both mentions a Texan's two Chevy trucks and contains useful technical information about refrigirative gasses.

I have been proven wrong by slashdot once again.

Re:No more freon in cars

[Itchy Rich]

You mean compared to countries like Germany and France ? (Well known everywhere as bastions of conservative capitalism and mercifully free of the unionised workplace).

What, free from unions like this and this and this you mean?

Re:No more freon in cars

[MountainMan101]

dihydromoxide? You mean hydrogen oxide (no need to use mono or di or any other crap).

Secondly, injecting H2O into the body would kill someone. That's why hospitals use glucose or saline solutions.

Re:No more freon in cars

[curious.corn]

Speaking of Germany: the country has done extremely well for decades. It has one of the most advanced mechanical engineering industries of the world and it's economy has always been the driving point of the whole contintent. Things started to wobble whith the reunification but let's be real, it's like suddenly running with a dead horse on your back. Yet they're still doing fairly well and shurely much better than other countries like Italy. You see, unions or high salaries are not a problem (what's wrong with high school teachers affording Mercedes Benz cars?) as long as they contribute to the sustainment of a market loop. The real point isn't about crushing labour, it's about taking responsibility and creating value add rather than going for a hit and run.

Italy for example is the worst example of antieconomic administration ever: entrenced 'corporative' unions that blindly protect privileges granted by unscrupulous policians for clientele sustainment; credit martket held hostage by individuals (yes, individuals... not even interest groups or boards) playing power games amongst themselves rather than just selling capital to investors.

Unions just represent part of the stakeholders, they're not bad per se. Of course in China, India or S America one can completely ignore them and eat the workers' cake but that doesn't mean being profitable, it's theft.

Eventually you have to admit that there's nothing bad in paying for labour as it produces the value add you sell and probably consumes it too! The point is going for the value add, there's nothing worse than stagnation with high salaries. Like sharks, economies have little if no buoyancy, if they stop swimming they sink.

Re:No more freon in cars

[wisdom_brewing]

Are you sure its 40 C converted to fahranheit? because if it is then most people who are apparently healthy are wandering around who really should be in hospital. You are usually quite ill at 38, 37 is considered healthy in england, 36.6 in countries which prefer a little precision.

Re:No more freon in cars

[Ignignokt]

Post taxes, probably. Post the 10%+ of them that are unemployed, certainly. Maybe their US counterparts in the automotive field will catch up to them in the latter category in the next decade, but they're not there yet.

Re:No more freon in cars

[Ignignokt]

I wouldn't necessarily lay the blame solely on the unions here. The management signed off on the pay/benefits plans too, right?

Re:No more freon in cars

[Temkin]

It's hot here in Texas, at or above 100F in the summer, and both of my Chevy trucks (an '02 and an '03) blow frigid air.

Here in Austin, we have Kali style traffic. I have yet to find a vehicle with R-134a refrigereant that will hold it's own in commute stop and go. I've tried Honda, Toyota's, Ford's, and Dodge's. The A/C will be just kind of tepid until you can sustain 1000 rpm and get some airflow over the condenser.

Only one car I've found has really kick ass A/C here in the summer. The hybrid Toyota Prius. I'm told it uses a sealed electric compressor that runs off the electrical side of the powerplant, but I haven't gotten a good look under the hood.

Re:No more freon in cars

[Jeff DeMaagd]

My dad has converted numerous R12-based systems to R134a and there haven't been any complaints. The "book" recommends changing several expensive parts, but he's slowly given up on that because of the cost, now replacing any leaking parts is the most he does outside of the refrigerant and oil.

Re:No more freon in cars

[WonderSnatch]

He said longer not faster.

That govenor is there to keep you uner the rated speed of the stock tires. This is a good thing.

Brett

Re:No more freon in cars

[caswelmo]

Where's the "Talking out of ass" mod?

I guess that would just be overused here...

Re:No more freon in cars

[cheesybagel]

I wonder how all those Arabs in the desert manage to survive without air conditioning... Could it be that:

a) they use shade
b) they wear clothes fit for the desert
b) they drink water

Re:No more freon in cars

[Anonymous Coward]

IAAME (mechanical engineer)and work in the cryo field, I'll contribute my $.02. Actually, Stirling cryocoolers do cost more to mass produce than regular A/C units. The tight tolerances and high grade materials required drive up the cost. Cryogenic applications require oil-free compressors and expanders because the oil would work its way to the cold head and freeze, destroying the cooler. Oil-free compressors don't have the reliability for an automotive application.

IAASAEM (Society of Automotive Engineers Member), I don't work in the automotive field, but I'm a geek interested in cars. From their magazine: The automotive industry calculates cost to the penny, and if there was some technology that was cheaper, improved mileage, or help cut emmisions (by not working the engine as hard), they would probably use it. There are numerous technologies in the works, but changing the A/C involves changing a massive infrastructure from manufacturing to maintanence.

Re:No more freon in cars

[the eric conspiracy]

There is so much wrong with using the word freon like this. Freon is a trademark of DuPont, and thus should always be capitalized. It is used to cover a class of halogenated fluorocarbons. Some of these halocarbons are ozone depleting, and some are not. Other manufacturers sell the same halocarbons under different trade names such as Genetron.

All car air conditioners use halocarbons, some use Freon, others Genetron, others other brands. If they use Freon, they may or may not be using ozone depleting types. I don't remember when the legislation banning ozone depleting halocarbons in auto air conditioners went into effect, but I am pretty sure that it has been several years since the lastnew car equipped with this type of refrigerant was sold.

Re:No more freon in cars

[mrgreenfur]

I believe they replaced the freon with R134a (which is, apparently tetrafluoroethane-1,1,1,2). So, yeah, no freon in cars or humidifiers, etc, for a while. Doesn't have much to do with it's efficieny I don't think.

Re:No more freon in cars

[bhiestand]

I doubt it. We paid a lot more than $3k/year on employees earning less than $30K/year. It was roughly 40-50% in addition to the salary we paid them. A $10/hour laborer cost us roughly $15/hour in taxes. IIRC, we had to match the social security and medicare benefits, pay some sort of money into unemployment, etc. Insurance costs were pretty bad too, along with all the OSHA-imposed expenses. Just buying all the government-mandated informative posters on minimum wage and how to report safety hazards cost a lot of money.

Re:No more freon in cars

[JDevers]

Actually 99.6 is the average core body temp (normal is +/- 1 from that). 98.6 is the average oral temperature which is a bit below core (as measured by rectal probe).

Re:No more freon in cars

[AKAImBatman]

Sorry, couldn't tell if you were just kidding or being sarcastic. :-)

Re:No more freon in cars

[harryk]

ugh ... people need to be informed about the chemistry behind what they speak of before speaking.

Freon is a generic term, loosley attached to the original liquid coolant, of R12 and slightly less so of R22. R12 is the chemical used in early model (pre 95ish) vehicles to act as a refrigerant in your A/C system. R22 is a coolant typically (and still today) used in home A/C systems. The R22 system, is similar to the same system as the one in your refrigerator (although I admit not knowing which coolant a fridge uses). In extremely rare instances do you need to recharge your refridgerator system with coolant, and only slightly moreso do you need to recharge your house's A/C system.

Newer vehicles use R134a as a replacment for the R12 system. There was another coolant that was available for a short time (and might still be) that worked in both systems, but I don't recall if it was very efficient, and it mostly served as a temporary solution for people that couldn't buy R12 (no license) and couldn't afford to buy the R134a conversions that were available.

At any rate, current R134a systems cool vehicles quite well. Come over any time, and I'll let you sit in my truck (Mazda p/u), engine at idle with the air blowing cold enough to make you want to change from your shorts back to pants...

Someone else posted the reasoning is due to the pressure needed in 134a systems, which I think explains why the early conversions couldn't keep up, the efficiency in design just wasn't there...

my 2 cents
harryk

Re:No more freon in cars

[Anonymous Coward]

yeah and the tradeoff is that they have unemployment from 12-15% while the US hovers around 4-6%

Re:No more freon in cars

[curious.corn]

As far as I know the inmate population is accounted for as 'employed'. US inmate population is in the 1 million range isn't it? Economic slump = lower living standsrds = increased crime rate = tougher laws = increased inmate population = lower/stable unemployment... Heh! cunning...

Re:No more freon in cars

[squiggleslash]

Seems to blow in my car, not suck.

You know, I live in the heart of Florida. It's hot here. My AC, my old AC, and my fiance's AC, all R134a based, are all absolutely fine, the odd leak notwithstanding. Trust me - if A/C in cars were a problem, I'd be complaining.

In fact, when I have my relatives over from Britain, they usually complain I make my car too cold.

Re:No more freon in cars

[AKAImBatman]

I was in an IRC interview with the MythBusters after that episode. They said that they are definitely considering revisiting the idea based on all the feedback they've gotten, and that it seems clear that they can only consider their current results to be preliminary.

Part of the problem they ran into with the episode was that it took so darn long to perform the experiments, that they really didn't have time (for that episode) to do a more in-depth test. :-)

Re:No more freon in cars

[ichigo 2.0]

Probably more like inmates aren't counted in the total available workforce. But don't other countries do this as well? I mean, inmates can't really be unemployed either; if they'd count then children should be counted as well, also being people unable to participate in the employment market...

Re:No more freon in cars

[Kordmp]

Not sure what you mean all 3 of my cars A/C is usually too cold to leave on high, after it cools the car off I always have to turn it down. Now my older 2 cars I admit aren't as cold as the old freon A/C's use to get but my new one I would have to say is just as cold as the old freons, which is way too cold anyway. I don't really need the inside of my car at 50F.

Re:No more freon in cars

[silicon not in the v]

Yeah, R134 is definitely less effective than R12. I remember on some older cars that still used R12, they could develop frost on the A/C vents because of how cold they blew.

Re:No more freon in cars

[Hachey]

A quick glance at wikipedia's article and on howstuffworks shows just why Stirling Engines won't be replacing car ACs anytime soon.


--
Check out the Uncyclopedia.org :
The only wiki source for politically incorrect non-information about things like Kitten Huffing and Pong! the Movie !

Re:No more freon in cars

[AKAImBatman]

Do you know the difference between an electric motor and a generator? The answer (which you probably already know) is that a generator creates electricity from mechanical motion, while a motor makes mechanical motion out of electricity. Beyond that, the two are the exact same device.

It's the same way with Stirling engines. You can apply heat to create mechanical motion, or you can apply mechanical motion to remove heat. The list of issues you're linking to are for using Stirling engines as powerplants, not for HVAC purposes. In the HVAC community, Striling engines are beginning to catch on for large-building AC. In the cryo community, Stirling engines are the definitive method for cryo-cooling. :-)

Re:No more freon in cars

[computechnica]

I'm a JoaT geek Myself. I converted My 91 Chevy Astro to R134 in the barn I built on my property that also has most of my computers in it. I converted some old mobile home central A/C units to cool the barn, and will cover the roof of it with solar cells one day when they get cheaper. Due to my rural location I also have a small satelite dish deck on the roof for TV and Internet, good for astronomy too. 8^)

Re:No more freon in cars

[WhiteWolf666]

Ok, Ok, you're right, I looked it up.

Between 90F-100F, then.

Re:No more freon in cars

[AKAImBatman]

Actually, Stirling cryocoolers do cost more to mass produce than regular A/C units. The tight tolerances and high grade materials required drive up the cost. Cryogenic applications require oil-free compressors and expanders because the oil would work its way to the cold head and freeze, destroying the cooler. Oil-free compressors don't have the reliability for an automotive application.

Interesting. I was under the impression that modern materials and boring techniques were beginning to catch up with this issue? i.e. We can now produce a bore that requires no libricant to operate. Granted, the price is probably quite a bit higher, but there's still the matter of economic scaling that can drive the price down.

Would a car AC necessarily need to be oil free? In most cryo applications, you're trying to get the temperature down to liquid nitrogen cooling levels. But in an airconditioner, you just want cool to icy air. That would place the air temperature at somewhere around 20-32F. Assume that the inside of the "cold piston" would have to operate in the range of about -10F to 0F, then couldn't we develop a synthetic lubricant to cover this range? I know that quite a few lubricants exist for arctic work that cover a much colder to hotter range.

The automotive industry calculates cost to the penny, and if there was some technology that was cheaper, improved mileage, or help cut emmisions (by not working the engine as hard), they would probably use it.

Fair enough. Unfortunately, it's a chicken and egg problem. Unless we have the engines in mass production, they're going to be more expensive. And they're not going to be in mass production until someone starts using them. Hmm... sounds like a good place for Venture Capital to jump in. ;-)

Re:No more freon in cars

[EnronHaliburton2004]

Yeah, but being unemployeed in Europe isn't as big of a deal as it is here.

In Europe, you still get healthcare and enough money to eat & pay rent.

Here, the government doesn't care if you loose your job, loose your healthcare, are evicted from your apartment and starve to death. Just get a job lazy fucker.

Re:No more freon in cars

[zippthorne]

It wouldn't be boring to mention. There is a filmmaking device invented for just this sort of thing. It's called a montage.

They also make a lot of unproven conclusions based on evidence shown, but that makes sense since they're not actual scientists/engineers (though they should've included at least one PE on their staff). The 'suction from sinking ships' comes to mind: their experiment did not take into account effects of scale. e.g. their pool model, the tugboat, and a real ocean liner would all have different reynolds numbers, their experiments should've been altered to take this into account.

The chicken gun was a particularly bad example of this as the high-speed video showed exactly what they were claiming to disprove: the frozen chicken impact took place over a shorter time period and over a smaller area --- it did not "spread out as much" --- Since they noted that the total impulse was the same whether frozen or not, the conclusion is that the pressure exerted on a real window would've been greater for the frozen chicken. Whether the frozen chicken would break the window and the thawed chicken would not is a matter for more trials, but their experiment showed that it was indeed possible.

Also, they should consider more than one myth-historian. I vaguely remember at least one episode in which the myth as I knew it (and as found in snopes) was not the same as the one she described. Coincidentally, her version was easier to disprove. Certainly, being myths, there are more than one version out there, but i would expect a myth-historian to know of the more popular versions and at least have heard of snopes.

That being said, the show is good. It's fun to watch and makes people think about physics. It could be great---in addition to thinking about physics they could have good physics, by doing exactly what they do now, but with real scientists to guide the experiments. I expect that either Jamie & Adam are too narcisistic to allow additional experts or ---far more likely---Discovery doesn't want to spend much more money on this than they do on "remarkeably homogenous chopper-of-the-week" (or is that "the learning channel" I keep getting them mixed up because the programming has slipped so far into MTV land)

Re:No more freon in cars

[mr.mighty]

Probably more like inmates aren't counted in the total available workforce. But don't other countries do this as well? I mean, inmates can't really be unemployed either; if they'd count then children should be counted as well, also being people unable to participate in the employment market...

But no other western industrialized country incarcerates nearly as large a percentage of its population as the us. I know that between the difference in incarceration rates and the way the numbers are tabulated, most of the difference between US and Canadian unemployment rates disappear, whereas Canadian rates are generally 2% - 3% higher.

Re:No more freon in cars

[MemoryAid]

Are you sure its 40 C converted to fahranheit?

No.

The formula I should have used is included below for reference:

F=9/5*C+32

Re:No more freon in cars

[pallmall1]

Maybe it's the cars they make?

How is this flamebait? I wasn't referring to the Pinto (and it was a Ford, anyway.)

Re:No more freon in cars

[tricorn]

Driving from Illinois to California and back, it was quite obvious that running the AC didn't hurt gas mileage appreciably, even in 90-plus degree weather. Opening the windows put more of an obvious drag on the car than turning on the AC (e.g. cruise control - watch the tach when you change conditions, or feel the gas pedal move). It was also interesting that the car I was driving seemed to get better gas mileage at higher speeds (e.g. 70-75 through Colorado) than at lower speeds (e.g. 50-55 in Iowa). The effects of up-and-down mountain driving, and high altitude driving, were less consistent.

Re:No more freon in cars

[ppanon]

Yeah, but after ambient temperature is a certain amount over core body temperature, you gain more heat from heat transfer of the air to the skin than you lose from sweat evaporation. Your pores can only put out sweat at a certain rate and there is thus an upper limit to the amount of heat that can be shed by the body through seating. However as you increase the air volume that comes into contact with your body, you increase the amount of heat that your body will absorb through direct thermal transfer.

I was driving around Phoenix at the end of June in extremely dry, 108F weather. I tried rolling down the window to see if it would be possible to use sweat cooling instead of AC and found that I quickly started cooking a lot faster than when I was just walking around earlier, even though I was expending less energy driving.

So yeah, my 100F number might have been a little low, but it doesn't requiring going over that temperature by much before no amount of airflow increase due to speed is going to help. Otherwise, nobody would sell convection ovens.

Re:No more freon in cars

[instarx]

Your statistics are misleading and mis-applied. The German unemployment rate for June 2005 was a whopping 20.5% in the former East German sections of Germany, while the country's overall unemployment rate was 12.5%. Therefore the western, industrialized, parts of Germany have a rate roughly comparable to the US.

The overall 12.5% jobless rate is clearly not a result of unionization or social programs as you imply, but from re-unification problems. I dare say that if Mexico were added to the US overnight our unemployment rate would skyrocket too.

Re:No more freon in cars

[Asic Eng]

US inmate population is in the 1 million range isn't it?

About 2.1 million according to the International Centre for Prison Studies The prison population rate is 726 / 100,000 in comparison Germany has 96 / 100,000. The population there is 82.6 million, so in order to get to the same rate, Germany would have to imprison (726-96) / 100,000 * 82.6 million = 520,380 people (more than 6 times the number imprisoned there now).

Re:No more freon in cars

[unitron]

You forgot the most important part:

d)they don't have to fight the humidity

freon?

[schematix]

The peltier chips used in the device are more energy-efficient, last between 20 and 30 years, are solid-state, and don't harm the environment with ozone-depleting freon like today's car air conditioners."

Ahem. "Today's" cars use R134a refrigerant, not ozone-depleting freon. This has been the standard for a little less than ten years now.

Re:freon?

[schematix]

screw all you people modding this post as redundant....this was one of the first 10 posts in the thread and the first to even mention R134a, which a lot of people have picked up on after i made this.

Re:freon?

[Technician]

In the new Prius, the AC is no longer belt driven. This eliminates the shaft seal, a common wear and slow leak source. The new AC is electric using a sealed compressor much like a home AC unit.

The peltier chips used in the device are more energy-efficient, last between 20 and 30 years,

I have a solid state ice chest. I don't believe the expected life rating when applied to a solution where condensation is present. It does not apply when they are used in high humidity. Corrosion from condensation kills these in a very short time. The module in my fridge died long ago from condensation caused corrosion. I would not want these in any application that runs below the dew point. Since my AC in my car is designed to run below the dew point to defog windows, there is no way I want a cooling solution that dies when it gets wet. Speaking of more energy-effecient; More effecient than what? Older modules, compressor driven? I have not seen any peltier chips ready to replace the compressor driven freezers and window AC compressors. They simply don't remove enough heat.

An advantage a working fluid AC has over a solid state solution is the hot side can be far removed from the cold side. The radiator for most car AC units is in front of the engine in cool air. A solid state AC would have the hot side behind the engine next to the passanger compartment. Just where were they planning on putting their waste heat? A typical car AC unit is over 20,000 BTU's. How many BTU is their system?

Re:freon?

[n1ywb]

Unless the refrigerant is flowing around the electric motor, which I doubt, there is still a shaft seal inside the sealed unit. Also this seems pretty silly since you're now converting mechanical energy into electricity in the alternator or whatever your prius has, then converting it back into mechanical energy to drive the compressor. Granted that allows the AC to work even when the engine isn't running but it does decrease the overall efficiency of the AC system. Maybe that loss is made up for in the whole hybrid system...

Let's not forget this is the local yocal salt lake city paper promoting a couple of local yocal kids, not a serious technical journal with serious technical data to back up their claims.

Re:freon?

[Technician]

Unless the refrigerant is flowing around the electric motor, which I doubt,

Hint,, Look at the compressor in the back of your refrigerator. Look for a motor and shaft..

Yes, it is a sealed compressor with the motor completely sealed inside the can. There is no shaft seal.

Frigidaire got to them...

[aapold]

Frigidaire got to them. Don't mess with the cooling conglomerates...

Re:Frigidaire got to them...

[MrNonchalant]

...they'll put you on ice.

Ka-ching!

Re:Frigidaire got to them...

[irtza]

Luca Brazzi cools the fishes

sweet!

[sams2100]

I can now overclock while I drive!

Re:sweet!

[Mars2020]

Air conditioning? Pfff....I just keep a bag of ice over my loins while I drive....

great.

[Forbman]

Now I can overclock my car's OBD-II computer.

Re:great.

[cynic10508]

Now I can overclock my car's OBD-II computer.

Don't bother. It's time to upgrade to the CAN interface.

Google Cache

[j00bar]

If you're having trouble seeing the article, try this: Google Cache

Re:Google Cache

[demogorgonx]

Here's the whole article:

BLUFFDALE - The code name, Space Beast, was one they came up with in the wee hours of the night.

Tyler Lyon, Daniel Winegar and Chad Thornley were overtired and giddy as they tackled a science fair project. Their idea: Eliminate the use of Freon in automobile air-conditioning systems by relying on the Peltier effect - of course.

"We aren't planning our lives around making air conditioners," Lyon explained. "We wanted to do something to help the environment and the economy."

But what began as a Riverton High School physics class assignment nearly two years ago has morphed into an award-winning, internationally recognized invention.

Lyon and Winegar, two recent Riverton graduates - Thornley graduated in 2004 and is now on an LDS Church mission - won the first-ever Ricoh Sustainable Development Award in May when they competed against 1,400 other worldwide invitation-only entries at the Intel International Science and Engineering Fair in Phoenix.

Aside from the $50,000 college scholarship the two 18-year-olds will share, the budding engineers are jetting off to Japan today for a 10-day visit on Ricoh's dime. The office equipment and electronics company, a leader in the field of sustainable development, has invited the Utahns to attend the World Expo, address Ricoh executives, tour their research and development lab, meet with government officials - including the Minister of the Environment - and sit down with Tokyo University professors.

"It's been a total, unbelievable dream," marveled Tyler's mom, Diane Lyon, last week. "They're just typical boys. But when someone believes in you, amazing things can happen."

Physics teacher Kari Lewis, who recently left Riverton High, said trusting in Lyon and Winegar was easy.

"They came up with this idea . . . and they made it work," she said. "It's a perfect solution to an incredible problem."

Today, the young inventors say, U.S. drivers use about 7.9 billion gallons of fuel each year to run their air-conditioners, which draw power from the engine. By adopting their contraption - which taps into the electrical system, using fans to blow hot air through five Peltier chips and then releasing cold air - they say the country stands to save 3.9 billion gallons of fuel annually, or about $10 billion based on current gas prices.

Furthermore, the product would free drivers from Freon - which despite improvements, remains an ozone-depleting chemical in current air-conditioners. The Peltier chips, which they purchased on eBay for $9.99 each, have a life span of 20 to 30 years and an unfaltering cooling capacity. And like every component in the Space Beast, which can be minimized in size to about 2 inches in width, the chips are recyclable.

As a young boy, Lyon's parents said he tore apart and reassembled household electronics - CD players, clocks, an old stereo that didn't work until he fixed it. And while Daniel's mom, LouAnn Winegar, was grateful her son was "not a take-apart-person," she said her boy's love for science, engineering and computers has been consistent.

"It's nice to see all of his years of interest and hard work being recognized," she said.

The two-year process of fine-tuning, however, was not without its glitches. When the teens were trying to convert a blow-dryer fan from AC to DC power, a miswiring gave Lyon a doozy of a shock - "a low-enough amp that it couldn't really stop my heart," he said. And there was that computer power strip that they managed to ignite, before throwing it outside in the snow, only to retrieve it two days later to recycle its parts.

Despite the setbacks, and bouts of procrastination, the teens didn't give up. When they weren't playing computer games, skiing, snowboarding or, in Lyon's case, rock-climbing, they buckled down, sometimes working through the night. Their focus nearly cost them graduation - they had to scramble to make up work in other classes

Re:Google Cache

[Alsee]

Salt Lake Tribune printer version of article working link.

-

Re:Google Cache

[starm_]

I concur. I helped build a beer refrigerator 3 years ago for a university engineering project using the same technology. It's nothing new. Its an impressive project for high school students. They probably did have to do some electronics to regulate the power so that they wouldn't damage the chips. But it's neither new nor inovative. Its an obvious use for these cooling chips that they bought on ebay.

Re:Google Cache

[darkonc]

Oh give me a break! This is not new! Hey peltiers get hot on one side and cold on the other, so lets bolt heatsinks and fans to both sides! Hey we have something here!

Sometimes a basic idea is well known, but turning it into something that is commercially viable for a given application can still be a real issue. The idea of using a fillament to turn electricity into light was well known before Edison became famous for creating a bulb that was reasonably efficient, and long-lived.

Creating a simple cooler with a commercial peltier device should be an almost trivial project. Creating something that would be a viable vehicle air conditioner really might have required some decent work to scale it up probably.

An example of the problem would be Nuclear power plants: (early?) US designs were apparently a simple scale-up of breeder and/or nuclear submarine plants. That didn't work to well, and resulted in systems that needed to be shut down on a regular basis (According to one Arizona resident I talked to their power plants have more than a 50% downtime). Canada's Candu system, on the other hand was designed from scratch as a commercial power generation system with a near-100% uptime, and significant downtimes for the Ontario plants are national news.

Ozone depleting

[atrus]

Last I check, most cars have R-134a, or have been retrofitted to run it. No one uses ozone depleting CFC refrigerants anymore (at least in the US).

Re:Ozone depleting

[schnikies79]

You can still get r-12, it's high as heck though.

What article

[Ropati]

I would be nice if you could post a story that was still active:

The Salt Lake Tribune
The content item you have requested is no longer available.

Re:What article

[OrangeGoo]

But this is Slashdot. You're supposed to be mean and bitter. :)

*zip!*

[Kid Zero]

Wow... gone before the slashdotting!

Freon isn't used in new cars!

[DarkHelmet433]

Freon (R-12) hasn't been used in new cars for something like a decade now. R-12 is an ozone depleter. It hasn't been manufactured in the US since the mid 90's or so

Newer car air conditioners use refrigerant R-134a. This is *not* an ozone destroyer, but it is still a greenhouse gas.

Peltier coolers use electricity, which is generated by the horribly inefficient internal combustion engine which produces greenhouse gasses and other toxins by the boatload.

It's all bad. :-(

Re:Freon isn't used in new cars!

[TykeClone]

Peltier coolers use electricity, which is generated by the horribly inefficient internal combustion engine which produces greenhouse gasses and other toxins by the boatload.

But is the load on the engine when running the AC more than if it was attempting to cool air using the Peltier cooler?

Re:Freon isn't used in new cars!

[Muerte23]

Peltier coolers use electricity, which is generated by the horribly inefficient internal combustion engine which produces greenhouse gasses and other toxins by the boatload.

Not to nitpick, but the compression cycle of regular car AC is also powered by the motor...

Plus, if your alternator can handle it, the peltier is probably much lighter, and certainly much smaller, further improving your engine efficiency.

m
this is not a sig

Re:Freon isn't used in new cars!

[Neoprofin]

I'd like to see you move 3000lbs 20 miles using only a gallon of fuel.

Re:Freon isn't used in new cars!

[DarkHelmet433]

To refer to posts above, the peltier coolers have a severe disadvantage.

#13120684: Normal peltiers have an efficiencies of less than 30% Modern air conditioners have an efficiencies approaching 400%.

#13120746: Modern aircon works by using matter phase change and using pump to move the fluids. It transfers more heat than the energy consumed in moving the fluids.

So while I don't have one of these, I'm really really sceptical that the CO2 and other greenhouse emissions per unit of cooling by a peltier can get anywhere near a modern air conditioner.

Re:Freon isn't used in new cars!

[truckaxle]

The point his is trying to make is that a vapor compression air conditioner has a COP of about 4 whilst a peltier effect conditioner is around .3.

Therefore you have to use more energy to cool the car and that energy comes from the fossil fuel powered internal combustion engine albeit indirectly via the alternator. In this case around 10 times more energy, not very efficient.

Re:Freon isn't used in new cars!

[ErichTheWebGuy]

OK, allow me to put some things into perspective. In addition to being a MCSE, A+, etc. certified geek, I also hold EPA certification to handle refrigerants and to service and install refrigeration systems in commercial, residential, and automotive applications.

The parent poster is absolutely correct, R134a is a greenhouse gas. However, that statement should be qualified: it is only a greenhouse gas when it is released into the atmosphere. Modern technicians use recovery equipment to remove refrigerants from cooling systems (everything from your freezer to your central A/C). The refrigerant is either recycled, or disposed of properly.

As long as we are all conscious about our environment (and we all should be, lest anyone turn us in to the EPA, causing us to have to fill out the reams of paperwork!) there is no problem. Oh, and there is always that pesky thing about preserving the planet for generations to come :)

I, for one, am quite sick of people blowing things out of proportion when there is no real problem. Having said that, kudos to the two teens for their inventive spirit. Maybe with some refining, the invention will prove more efficient and ultimately prove commercially useful!

Re:Freon isn't used in new cars!

[jimi the hippie]

and R-134a IS FREON. (FYI)

Re:Freon isn't used in new cars!

[Brandybuck]

To put it into perspective, H2O and CO2 are also greenhouse gasses, but that doesn't seem to stop people from exhaling...

Re:Freon isn't used in new cars!

[Michael Hunt]

Um...
(quick conversion to metric units, very rough)

3000lbs ~= 1.5 metric tons.
20 miles ~= 32 metric kilometres.
1 US gallon ~= 3.8 litres.

My 1995 Ford Fairlane weighs 1.7 metric tons (tare) plus payload plus fuel. I average 10.5 litres of fuel used per 100KM in mixed highway/city driving.

Some quick maths: 10.5L/100 divided by 100, multiplied by 32 gives me 3.36 litres per 32 kilometres, which is roughly .89 gallons per 20 miles. AND it weighs 400 imperial pounds more.

Re:Freon isn't used in new cars!

[DarkHelmet433]

My closing comment was too brief. I probably should have said "there is no such thing as a free lunch".

See my comments in #13120817about the efficiency aspects of it though.

Peltier coolers contain no greenhouse gasses nor ozone depleters. But they still need lots of energy to run, which comes from a greenhouse gas producer (internal combustion engine).

Car A/C systems contain greenhouse gasses which can escape to the atmosphere in accidents or when idiots do stupid things. Older ones contain ozone depleters. And they too use energy to run.

A decent car A/C system should leave a peltier system in the dust for energy efficiency. Of course, that is assuming there are decent car A/C systems.

And then there's the financial incentives. R-12 is increasing in value at a quite nice rate. It is extracted from old A/C systems and resold to repair other systems that haven't been retrofitted yet. R-12 is quite valuable these days.

Of course, all the environmental impact of the gasses assumes that the gasses escape... The $25000 fine for deliberately releasing R-12, plus the high price of R-12 makes it well and truely worth recovering.

I bet more geeks have released difluroethane or tetrafluroethane into the atmosphere via dust remover / compressed "air" cans than they'll ever release via car airconditioner leakage. This "air" can is of course the same gas that is used in R-134a (tetrafluroethane).

Re:Freon isn't used in new cars!

[DarkHelmet433]

Umm, no.

"Freon is a trade name for a group of chlorofluorocarbons used primarily as a refrigerant. The word Freon is a registered trademark belonging to DuPont."

R-12 refrigerant is a chloroflurocarbon. ie: Freon.

R-134a is tetrafluroethane. ie: not Freon.

Re:Freon isn't used in new cars!

[simcop2387]

#13120684: Normal peltiers have an efficiencies of less than 30% Modern air conditioners have an efficiencies approaching 400%.

in that case i better run mine all the time! its going to generate power instead!

Re:Freon isn't used in new cars!

[bewebste]

Peltier coolers use electricity, which is generated by the horribly inefficient internal combustion engine which produces greenhouse gasses and other toxins by the boatload.

Or electricity generated from the brakes on your hybrid car...

Re:Freon isn't used in new cars!

[jnik]

Modern air conditioners have an efficiencies approaching 400%.

So if I turn on the A/C, gas goes back into the tank? "In this house, we obey the laws of thermodynamics!"

Re:Freon isn't used in new cars!

[WindBourne]

• Weight of Peltier vs. Modern AC? Peltier is under a Kg, while modern AC is 20-30Kg?
• Weight and complexity of hooking into serpentine belt?
• Adding the controls?
• Servicing charge on the AC for changes (none for peltier). Will need recharge every so often.
• In fact, how often do you service a peltier (NO moving parts) vs. an AC.

One nice advantage of this, is that it will fit in with the new hybrids/electrics. I suspect that down the road will see increases in how these work IFF they are accepted as normal.

Re:Freon isn't used in new cars!

[ErichTheWebGuy]

Good point, and also absolutely correct. In fact, we don't see people running in droves to burn down the rain forest, in fact, quite the opposite is true. Do plants (including the rain forest) emit greenhouse gasses (CO2)?

Another theory of mine (and it is strictly a theory, absolutely *zero* research has been applied to proving or disproving this theory) is that as we develop more and more enclosed space, we are heating the planet more and more. Here's how it goes:

Air conditioners remove heat from the air. That fact is known and well documented. Consider all of the skyscrapers, office buildings, high-rises, and apartment buildings in modern society. Hot air rises, and cool air sinks. We all know about convection as a method of heat transfer. More energy is used to cool the upper spaces of a structure, since the heat is deposited there (it has nowhere else to go, after all!).

Consider this: as an air conditioner draws air into the system, passing it through the evaporator coil, it removes heat from the air by allowing the refrigerant to absorb its heat. As the refrigerant passes through the condenser coil, it removes this heat through conduction via the fins that are attached to the condenser coil and the fan that moves air over those fins. Where does that heated air go? Why, to the atmosphere.

*GRANTED* most of the heat is lost to radiation into space after dark. but the contribution to rising of average temperatures cannot (IMHO) be denied.

Also consider our refrigerators, freezers, beer coolers, water dispensers, etc. etc. These all have to vent heat from their respective cargoes somewhere, which is typically our homes/offices. That heat is then vented outside by our air conditioners.

It seems small I know, but the cumulative effect could be staggering (like every car in the U.S. getting 1/100 M.P.G. lower fuel economy). I theorize that these very systems contribute to global warming, and will continue to do so as we build more urban populous centers and continue to build higher into the sky. I welcome any contrary evidence.

Re:Freon isn't used in new cars!

[juanescalante]

Peltier coolers use electricity, which is generated by the horribly inefficient internal combustion engine which produces greenhouse gasses and other toxins by the boatload.

Isn't it possible that in combination with new hybrid cars this will be an actual environment friendly alternative?

Re:Freon isn't used in new cars!

[turbod]

Are you nuts? You need to take some heat pump theory, or just plain old thermodynamics.

Heat pumps are cheaper to run because they don't _create_ or _take_ any more energy than necessary to compress and move the fluid through the system. The temperature difference between the hot and cold side, combined with phase change properties in the fluid is what makes air conditioners so efficient.

You have to power the pump, but no more.

Compare a 20,000 BTU strip heater's power consumption with a 20,000 BTU heat pump.

Simply put, you need to check your facts before you post cheeky stupid comments.

Furthermore, the people who gave this award to these kids are most definitely graduates of the New Math way of thinking, ie., no point in obeying proven facts when we can make up what we want along the way to make older proven and better technology look bad by putting kids faces on it.

The educated know what New Math was really about --- but it has been corrupted into what we see here in this article, which is just plain stupidity and laziness about checking facts.

A Peltier Junction emits more heat than it moves, and fails the test for good technology at the scales where a compressor is not too much of a burden on the rest of a design. In addition, running a current drain system like a peltier junction off of 12Vs at the size required for a car (20,000 BTU or more), would require a alternator that would be so inefficient at out of rpm conditions, that twice the amount power wasted at the peltier, at least, would need to be wasted just to keep the stupid alternator rotating against the humongo bearings and cooling fan necessary to cool the damned thing.

Geez people, read the physic manuals before you make stupid assessments.

TurboD

Re:Freon isn't used in new cars!

[ErichTheWebGuy]

bleck... I see now the error of my post, of course plants do not emit CO2... So, error recognized and (hopefully) corrected!

Re:Freon isn't used in new cars!

[Aqua OS X]

Nah, the coolers will be installed Priuses, and they will only turn on when the car breaks.

Re:Freon isn't used in new cars!

[Hugonz]

In addition to being a MCSE, A+, etc. certified geek

Syntax error.

Re:Freon isn't used in new cars!

[ColaMan]

Let's see here....

Fatter alternator due to the giant amount of power consumed by a 40% efficient peltier. (Move 1 unit of heat with 2.5 units of power in)

VS

A/C compressor with a COP of 3 (move 3 units of heat for 1 unit of power in)

All that energy's got to come from somewhere. A typical car A/C is around 3-4kW. Or about 2kW of power to drive an A/C compressor. So, for a peltier equivalent, that's 10kW of electrical power from the alternator, driven from the engine, for the peltier array to get the same cooling effect.

I'll stick with compressor-driven A/C for now, thanks.

I keep toying with the idea of a twin ammonia-calcium chloride adsorption A/C, driven from the excess heat in the car exhaust. Heat one salt pack, release ammonia to condense in accumulator and tx valve , which then gets drawn to the other previously-heated-and-now cooling salt pack via an evaporator. When one pack is expended, direct hot exhaust gases to heat the other pack and continue. One of these days I'll get arond to it.

Re:Freon isn't used in new cars!

[Anonymous Coward]

Air conditioners are no different from any other electical load; the laws of thermodynamics require that ultimately a 1 kw air conditioner will generate exactly as much global heating as a 1kw electric fire. The fact that the thermal signature of a building is biased towards the roof really won't have any significant effect on air flow beyond a few hundred feet away. In any case the global warming contribution of the CO2 from the fossil fuels that were (almost certainly) burnt to provide the power to run the AC will greatly outweigh the direct thermal contribution.

Re:Freon isn't used in new cars!

[arodland]

Simcop's joke was based on the grandparent's (I think) misuse of the word "efficiency". What the grandparent meant by 400% efficiency was that it moves 4 times as much heat than it emits itself -- but what "400% efficiency" means in the rest of the world is "takes one unit of energy as input, and outputs four units of energy" -- i.e. free energy.

But your grammar-deficient tirade was fun anyway.

Re:Freon isn't used in new cars!

[Jeffrey Baker]

Yes, and if you weren't an ignorant twat you would realize that modern refrigerators have coefficients of performance in excess of unity. Well in excess, normally.

Re:Freon isn't used in new cars!

[Velox_SwiftFox]

I would think that simply spraying the condensation from the A/C onto the condenser, as done in home window units, would add a useful bit of energy efficiency. Maybe even assist the radiator.

Re:Freon isn't used in new cars!

[ErichTheWebGuy]

I appreciate that, insightful indeed... But the point remains, the more square feet of enclosed space we build, the more we heat our planet. I have not completely spelled out my theory, as it is only slashdot, and the fact that I have not done any research still looms over my head. Anyway, a couple of points I have not yet considered have been brought up, thanks!

Re:Freon isn't used in new cars!

[dbIII]

Not to nitpick, but the compression cycle of regular car AC is also powered by the motor

Yes, but it is far more energy efficient than a thermocouple driven in reverse. There's good reasons why this sort of thing wasn't done fifty years ago in this situation, but was done fifty years ago where space was tight and energy efficiency was not the issue. We have known about the physics involved and the materials used here for decades - peltier cooling has just come to prominance lately because it's a way to cut down on the number of moving parts and is getting into home computers.

These kids won against others because they did something others with knowlege knew was no big deal, and those that judged only looked at it superficially and thought it was a big deal.

It reminds me of a famous artist that developed an apparent way of dramaticly inproving fuel efficiency in internal combustion engines. By putting a spacer under the carby he optimised the motor to run while idling, dramaticly reducing the amount of fuel it used on a test bed - because the motor had been optimised to run at a specific load. He completely missed the point (that you want the motor to do something) and the press didn't realise either. The judges in this competition have also missed the point and gone for drama over utility.

Re:Freon isn't used in new cars!

[mobets]

I don't know much about cars or electronics, but I'm wondering if using more electricity makes it harder to turn the alternator (assuming you don't have to install a larger one to power the peltier). If not, then wouldn't the extra energy you are using for the peltier have symply been released as heat any way?

Re:Freon isn't used in new cars!

[uncqual]

Won't the building eventually return to the average temperature of the surrounding environment (for example, when the AC is shut down for the weekend or, in extreme cases, when the building power is shut off prior to demolition)? Thus the effect is temporary. The heat originally pumped out of the building/contents will eventually be reabsorbed by it. As has been noted, of course, there is a bunch of heat (and, with our current infrastructure, greenhouse gas) produced in the process of generating power for the compresser (and some wasted heat since the compresser has friction which causes the moter/compressor to convert some of the input energy to heat). But, what do I know... I'm a software guy who was hacking ("hacking" meant something different in the 70's than it does now!) in the computer center instead of going to the classes on this stuff... Feel free to correct me!

Re:Freon isn't used in new cars!

[The_Dougster]

The design does have some advantages.

A solar panel on the roof or rear deck could run this unit all day, keeping the temperature down inside your vehicle. You can probably get a pretty decent solar panel for the price of a replacement AC pump.

Consider the metal components and precision machining required for parts in a current automotive AC system versus a couple pelters, heatsinks, and possibly a small auxiliary electric fan. I think the component and machining cost savings would be substantial enough that AC could be equipped as standard equipment on all vehicles.

Alternators don't waste power needlessly, the load that they put on the engine depends on the amount of current that they are producing. So switching off the Peltier doesn't cost you anything. I know AC compressors have clutches too but I'm just pointing this out.

Re:Freon isn't used in new cars!

[srw]

> bleck... I see now the error of my post, of course plants do not emit CO2

Well, actually, they do. Most plants emit some CO2 at night. Of course, during daylight, they absorb more CO2 than they emitted at night, but still... Your statement was technically correct.

Re:Freon isn't used in new cars!

[The_Dougster]

I keep toying with the idea of a twin ammonia-calcium chloride adsorption A/C

Ammonia might not be a good idea for Joe Lugnut the backyard mechanic. One good whiff of ammonia can actually kill you. Granted, its properties are a dream for refrigeration cycles, but there's a reason why it isn't used in consumer products.

Theoretically, one could stick reverse Peltiers all over the catalytic converter too, and use the thermoelectric generated power to run the cooling Peltiers. It would be grossly inefficient and pretty damn expensive, but it would basically give you free cooling with no power loss, similar to your idea above. I suppose the cost could be brought down by using cheaper Seebeck junctions at a trade-off in output power.

Re:Freon isn't used in new cars!

[ErichTheWebGuy]

Thank you for that... That only goes to prove the fact that I have done zero research into my theory!

Re:Freon isn't used in new cars!

[ErichTheWebGuy]

I agree completely with you.. The effect is probably even more dramatic than you convey here. I even theorize that the majority of the heat that we vent from our structures is vented into space at night via radiation. I still contend that our venting of heat from our structures is contributing, even if ever-so-slightly, to the rise of the avrage temperature that has been observed as of late.

Re:Freon isn't used in new cars!

[The_Dougster]

I'm wondering if using more electricity makes it harder to turn the alternator

Yeah, it definately does. To get 1W of electricity you might have to put in 1.5W of mechanical power, the variance is a curve and there's typically a sweet spot where the efficiency is maximized for any particular alternator.

One horsepower is about 750W, so for a reduction of 1hp from your engine output you might get 500W of electricity which would be about 40 amps in a car.

Re:Freon isn't used in new cars!

[zippthorne]

You don't need to know anything about cars or electronics, only about physics. specificaly that conservation of energy thing. If you are drawing more energy from the alternator, it must come from somewhere. If it is not coming from the engine in the form of increased load, then it must be coming from the battery in the form of draining it.

If you could draw any amount of current from the alternator without increasing the mechanical load then there would be no reason for gasoline powered cars at all: just power an electric drive with the alternator and bam, perpetual motion car!

Re:Freon isn't used in new cars!

[The_Dougster]

Thus the effect is temporary. The heat originally pumped out of the building/contents will eventually be reabsorbed by it.

Actually, I think all AC's blow out substantially more heat than they remove. The electricity you are putting into the unit is converted to heat and blown out the back along with whatever heat you manage to remove from the interior. That electricity isn't just disappearing, its being emitted as heat.

Re:Freon isn't used in new cars!

[Trepalium]

Plants do emit CO2, especially when there's no sunlight or water available. Dead or dying plants also produce it while they rot. When both sun and water are available, they produce O2.

It seems small I know, but the cumulative effect could be staggering

The fact that "heat pockets" exist around cities and other major centres is well known. In fact, it's a major reasons why cities tend to create their own weather. See this article or this one for more details. They call it the "urban heat island". It causes storms when the conditions shouldn't be right for them, extends the growing season in both fall and spring, and produces winds. This phenomenon has been observed since the early 1800s, and it's only getting worse.

Instead of targeting A/C, the researchers have pointed to the more mundane things, like roads and parking lots (the dark colour of asphalt absorbs sunlight and turns it into heat) and dark roofs. Areas with sufficient tree coverage, on the other hand, were much cooler. The seemingly trivial change of having a light colour roof can substantially reduce air conditioning requirements (although it can also increase heating requirements).

Re:Freon isn't used in new cars!

[kidgenius]

What's funny is that the judges are actually engineers, etc., whose jobs may require them to have knowledge of thermodynamics, or at least they were taught it at one point in their career. They sent out emails at work asking if any of us engineers would volunteer to be a judge in this competition. Really sad that something like this would win. The other entries must've sucked bad.

Re:Freon isn't used in new cars!

[ksheff]

It's also lethal. The amount in typical car A/C system could kill you if released into the passenger compartment. http://yarchive.net/ac/r134a_lethal.html

Re:Freon isn't used in new cars!

[ksheff]

The seemingly trivial change of having a light colour roof can substantially reduce air conditioning requirements (although it can also increase heating requirements).

That depends on what was done when changing the roofing materials. For a couple summers when I was in college, I had a job as commercial roofer. We would rip off the layers of tar and rocks that had built up over the years. In its place, polyurethane foam insulation would be sprayed down and then coated with a thick rubbery paint. We would normally see a big difference in how much the A/C units were running before we were even 1/2 way done. The cost savings due to using less energy all year round usually paid for the roofing in a couple years.

Re:Freon isn't used in new cars!

[Desert Raven]

One good whiff of ammonia can actually kill you.

If by "one good whiff" you mean to snort up a hundred ml or so directly into your nose, maybe.

I worked in a blueprint shop some years back. You had 12-16 people working in a room with 9-10 machines leaking ammonia into the room, eight hours a day, six days a week. Can't remember any of us dying from it. Heck, I can't remember anyone getting *sick* from it, even on the first day on the job.

And as far as the average person is concerned, they'd be clearing out of the area long before it reached harmful levels. Man, that stuff *stinks*!

Re:Freon isn't used in new cars!

[DarkHelmet433]

Heh, except that (again) there is no such thing as a free lunch. The electricity that you get from the brakes is simply a partial recovery of the kinetic energy that originated from the car engine. Unless you were pushing the car yourself, the energy ultimately came from the fuel in the tank in the first place. Even if it was from braking on a downhill run, the engine still had to work extra hard to get up the hill in the first place. And of course, at each transition there is wastage.

I believe it would be significantly more energy efficient to put an electric compressor in the car for A/C operation when the engine isn't running than use peltier cooler.

There are some distinct advantages to peltier coolers compared to fluid phase change heat pumps, but energy efficiency isn't one of them. They're cheaper, lighter and simpler (no noisy moving parts!!), but that's about it.

You want a peltier cooler for your aquarium during the summer, not your car.

Re:Freon isn't used in new cars!

[XO]

How can you have something 400% efficient? Wouldn't that mean it generates 4X the amount of output as is input? That doesn't work in my head. Or do I just not understand the concept?

Re:Freon isn't used in new cars!

[zippthorne]

Ok, back of the envelope time.

Total electrical power used by people on the earth:
~14 trillion kwh
(assume all of this is used to do something in a building and that no other energy is used by buildings and that all electric power is generated by non-solar means: no solar, hydro, or wind power)
1.5*10 terawatt

Total people on the earth:
~6.5 billion
~2000 kcal/day = 100 W

total: 629 GW

Total insolation:
2*pi*(6378 km)^2 * 1400 W/m^2 = 357 petawatt

Temp of earth that emits this power:

~280 Kelvin

delta-T caused: 0.0003 C.
delta-T if considering total human energy usage: 418 * 10^15 Btu / year = 14 terawatt => 0.003 K
since if P = {const}T^4: dT = TdP/(4P)

So whatever the temperature of the earth is, only about .003 degrees of it can be accounted for by the industrial output of mankind. The effect on the temperature of the earth soley as a result of human energy usage is significantly smaller than as a result of solar variance. If man is to have an effect on the earth's temperature it must be by affecting the heat transport rates.

Re:Freon isn't used in new cars!

[Desert Raven]

No problem.

1995 Jeep Cherokee Sport in-line 6cyl

Curb Weight: 3,000+ lbs not including driver
Highway mileage: 24mpg

And that's a vehicle that's almost 10 years old. The newer vehicles are quite a bit more energy-efficient.

3,000 pounds isn't all that impressive, really.

Re:Freon isn't used in new cars!

[uncqual]

I freely admit to not being in class when I should have - software I know, thermodynamics I know not -- but since this is /. and no expertise is required to opine on most any topic, I shall ramble into the valley of humiliation :)

No question there is heat produced to move heat from inside a building to outside a building (this heat being produced due to inefficiencies at the power generation facility, the lines/transformers between the generation facility and the air conditioning units due to line resistance et al, and within the air conditioning units themselves due to friction etc). However, I'm under the impression based (in part) on this thread that it takes as little as 1/4 of a joule to move 1 joule from inside to outside with conventional air conditioning (nearly the inverse with Peltier junctions which, long ago, this thread was about).

If my lame brained assumptions are valid, then perhaps for every erg moved from inside a building by conventional AC, less than an erg may actually be released as "net additional heat".

Of course, I'm so outside my area of expertise and so inside a bottle of Lagavulin that this is probably complete crap.

Re:Freon isn't used in new cars!

[Trogre]

*whoooosh*

Re:Freon isn't used in new cars!

[kesuki]

yea buddy... make fun of it. i am quite willing to wager that the grandparent poster makes a hell of a lot more money than you do while the it market is in a slump... and that s/he never has to worry about being laid off, because there is always someone who wants to be 40 degrees cooler than surface-level atmospheric temperature. i only wish that i had the smarts to have a fallback career like that, maybe then i would not be in a bankruptcy trial with my family being thrown into ruins!

The point (of the joke) is that A+ is so basic even the 'typical' best buy tech could pass it. And that MSCE certs are the MBA of the tech certification world. There are 'better' certificitaions but the point is he mentioned the most 'rice boy' of certs... Nothing wrong with embracing one's poser status, but real geek cred doesn't come as easy as a piece of paper. they are as you mentioned really good at getting you a 'job.' Certifications are just exactly about that, employment, nothing more..

It would be like being proud of being a CCNA When there are quite a few here who could breeze through the CCIE certification...

Re:Freon isn't used in new cars!

[wing03]

I see now the error of my post, of course plants do not emit CO2.

Er, don't they emit CO2 at night when there's no light for photosynthesis to occur?

Re:Freon isn't used in new cars!

[Temkin]

No... No... Certifications are about vendor lock in. Employment for the cert holder is secondary. The vendor's know that if you spend $5K on a MCSE/CCIE/RHCE cert, you're going to recommend that which you're certified in!

Seriously, have you ever seen a MCSE holder recommend against a MS product?

Re:Freon isn't used in new cars!

[karnal]

20$ says that a lot still leaks into the atmosphere.

I bought my house and I had 4 seperate service calls out on leaks in the AC unit. They finally told me to replace the unit, which I did, but if they could have told me that the 1st time, it would not have leaked all of it's r134a out of the coil.... instead of just doing a fill.

That really did piss me off.

Re:Freon isn't used in new cars!

[jimi the hippie]

In common usage any gas with an unpronounceable name used for refrigeration is referred to as freon.

According to one source:

"Freon - any one of a special class of chemical compounds that are used as refrigerants, aerosol propellants, and solvents. These compounds are haloalkanes, i.e., halogen derivatives of saturated hydrocarbons (see alkane). Every Freon contains at least some fluorine in its molecule, and most contain chlorine or bromine as well. Freons are generally colorless, odorless, nontoxic, noncorrosive, nonflammable, and chemically unreactive."

Wiki lists R-134a as a Haloalkane, which would match this definition as well.

Re:Freon isn't used in new cars!

[Octorian]

Having been through the CCNA and CCNP certifications, however, I can say that while Cisco does put a lot of their own stuff into those certs, they also put far more generally useful internetworking information.

True, if you handed me a non-Cisco router or managed switch, a CCNx might not know "the exact commands to type" to make it useful. But chances are that they would know exactly how to configure it, given some basic reference material. Protocols are standard and universal enough (ok, some are proprietary, but not most of them).

Re:Freon isn't used in new cars!

[bonius_rex]

Yep. I do it all the time. I'm an MCSA/MCSE and I frequently site that fact when I tell people how much windows sucks.

"I'm not just some linux hippy, I know *all about* windows [brandishes certificates], and I can tell you that it does, in fact, suck!"

Re:Freon isn't used in new cars!

[gfilion]

BSD is for people who love UNIX.. Linux is for people who hate Windows.

and MacOS X is for people who get laid!

Re:Freon isn't used in new cars!

[aXis100]

A phase change air conditioner doesnt "create" energy - it merely moves it around. It's like a 10000L petrol tanker only needing 100L of fuel to drive around.

The process for air conditioners is that cooling might be around 300% efficient (you pump 3 times the energy you consume), and heating is around 400% efficient (you pump 3 times, plus the consumed energy adds to the heat load).

Re:Freon isn't used in new cars!

[wheany]

and MacOS X is for people who get laid! ...by members of the same sex.

Re:Freon isn't used in new cars!

[CXI]

As a certified firefighter and geek, I can tell you that we certainly do not "use recovery equipment to remove refrigerants from cooling systems" when we arrive at an incident. Instead we are a little busy cutting people out of cars, extinguishing car fires, extinguishing house fires and the like. There are plenty of opportunities for this stuff to leak into the environment and if we do not have to use it, so much the better. BTW, does burning it turn it into a worse chemical?

Re:Freon isn't used in new cars!

[afidel]

I do it all the time. Of course the fact that I hold both an MCSE and started on my RHCE might have something to do with it =) I will generally recomend the best solution for my client/employer. If they are already an all windows shop with an IT staff with windows experience then of course I will likely recomend the MS solution (ISA server excluded). On the other hand if they have Unix/Linux experience and some windows infrastructure then it's simply about what best fits their needs with the smallest amount of capital outlay.

Re:Freon isn't used in new cars!

[jnik]

Would you care to demonstrate your knowledge and explain how the COP is measured? (I'm guessing it's joules moved / joules in and neither a fraction of Carnot efficiency nor energy out / energy in, as neither of those can exceed unity).

Re:Freon isn't used in new cars!

[metamatic]

Another theory of mine (and it is strictly a theory, absolutely *zero* research has been applied to proving or disproving this theory) is that as we develop more and more enclosed space, we are heating the planet more and more.

I read a great SF short story about this, decades ago. However, in the story it was the reverse problem--a new highly efficient heat pump had been developed, and everyone was sucking heat from the environment to heat their homes in winter. They had reached the tipping point, and the world had been sucked into a new ice age.

Can't remember the author. Wish I could.

Re:Freon isn't used in new cars!

[mobets]

My line of thinking is that since an alternator is a big spinning magnet surrounded buy coils of wire (maybe this is where I am wrong), when it is spinning at any given speed, it will be able to produce a certain amount of power directly related to that speed. If that is true, then ataching more electrical devices would not have any effect untill you tried to draw too much power. Then, all of the component in the car simply wouldn't receive enough power.

If all of this is true, I don't see why there would be a need for more mechanical load. The power would have been created any way as you are spinning it fast enough to make the power. You might have to spin it fater, or install a larger alternator to create enough power for the peltier, and I can see how that would take more mechanical energy.

Re:Freon isn't used in new cars!

[grgyle]

"...I welcome any contrary evidence..."

There are some basic physics nits to pick, I'd recommend reading up on guys like Carnot, Boyle, etc. When A/C coils pass heat to the outside surroundings, they are *not* creating a net increase in overall heat, they are simply moving existing heat from one place to another. The heat you feel coming off the back of your fridge is simply the heat that was contained in the interior of the unit. Once cool, the A/C only has to work to maintain a temperature difference, pushing already existing energy back to the outside--it doesn't continually pump heat willy-nilly into the atmosphere or create it from nowhere.

If left at rest, your fridge or office building would gradually warm as the energy migrates back in through conduction and convection, until everything is at equilibrium. Using your argument, if everyone turned off their A/C at once, we would risk global cooling as all of that outside heat gets sucked back into the buildings!

The only net heat increase happening is due to mechanical and electrical inefficiencies in the motor and compression cycle. All mechanical systems do this.

Re:Freon isn't used in new cars!

[Malcreant]

It's obviously impossible for technicians to capture and recycle all refrigerant ever manufactured. Refrigerant will be leaked into the atmosphere by accidents and careless users. It's irresponsible to be generating substances which can't be easily cleaned up. Over time, these substances will accumulate in large enough quantities to cause serious problems.

Also, what are the wastes produced by manufacturing Peltier chips?

These aren't ridiculous things to consider. It's the reality of the world we live in.

P.S. Isn't it ironic that the quest to cool ourselves forces us to cool ourselves even more?

Re:Freon isn't used in new cars!

[msaulters]

One good whiff of ammonia gives me uncontrollable nose bleeds. One summer while I was still in high school, I spent a week in a major university dorm which used ammonia-based cleaners. I woke up after the second night there to find my pillow was solid red from the blood soaking in.

A couple years later, I worked in a paint factory with my dad. I was driving a forklift, moving empty containers (6'x6'x6') that had contained industrial-strength ammonia. The lids on these containers had not been replaced, and the vapors gave me a nosebleed that wouldn't quit for 2 hours.

Ammonia definitely is a hazardous chemical, and you don't even wanna know what happens if you mix it with bleach.

Re:Freon isn't used in new cars!

[Desert Raven]

Ammonia definitely is a hazardous chemical, and you don't even wanna know what happens if you mix it with bleach.

I know very well what it does. I had a friend who thought it was the greatest cleaner in the world until I explained to him why he was getting dizzy from using it.

In this case, all that the ammonia does is to liberate the chlorine from the bleach, producing chlorine gas. So *technically*, it's not the ammonia that's the primary issue, it's the bleach.

Ammonia is highly alkaline, and is also mildly corrosive. It's the latter of the two properties that probably affects you so badly. But all that proves is that it's highly dangerous to *you*. The vast majority of people can handle being around fair amounts of it in well-ventilated areas with no bad effect.

Re:Freon isn't used in new cars!

[Joe5678]

It's also worth noting that R134a is used in a LOT of different products that simply expel it because it compresses well and therefore is a great propellant.

R134a is also known as Tetrofluoroethane, take a look at that can of compresses air we all have on or around our desk and you'll see that's pretty much all that's in there.

Re:Freon isn't used in new cars!

[Bobb Sledd]

It certainly would seem that way, wouldn't it.

Unfortunately you're not really creating any heat at all; you're just moving it around and concentrating it. Arguably you could even be cooling the planet by drawing heat from places that it normally couldn't escape and transfering it to the outside air, where it can eventually escape into the atmosphere... though I don't think this is really true either.

I think the overall net effect is zero (if you're only considering that effect.) More likely we are warming the planet from the fossil fuels we burn to power the air conditioners that end up insulating the planet and preventing heat loss.

Consider the number of parked cars there are in the world. Ever come out on a hot day only to singe your eyebrows when you open the door as a pocket of heat blasts you in the face? All that pent-up heat has to go somewhere! It must be heating the planet up more, right?

Re:Freon isn't used in new cars!

[Hugonz]

If you had read my post carefully, you would have noticed that nowhere I mentioned the air conditioning knowledge. Guess I'll have to explain the joke: the syntax error is between "geek" and "MSN".

Re:Freon isn't used in new cars!

[Neoprofin]

There are a lot of cars that get more than 20mpg, I drive two of them, I was aiming for the low end so that a person would have a chance of doing it themselves. My point being that you can bash the ineffciency of internal combustion engines all you want, they're still doing better than you would with a human under the hood.

Re:Freon isn't used in new cars!

[Neoprofin]

As I replied above at greater length I know cars can do it. I want to see you do it. In reply to the poster that said how dreadfully inefficent internal combustion engines are. They certainly beat the heck out of human labor.

Re:Freon isn't used in new cars!

[Cervantes]

No no no, you mean:

Hi, I'm Clippy! Would you like some help inspiring the wrath of linux geeks everywhere?

Hey, it looks like you're trying to admit taking it up the rump from Satan! Would you like some help with that?

Oh, god, now I'm suddenly picturing someone using clippy as lube to take it up the rump from Satan. Ahhhh!!! Out of my head! Out! Out!

Re:Freon isn't used in new cars!

[Bad_Feeling]

Not likely, even if the roof was covered with panels they would only produce a max of 160 -190 watts. By the time it gets to the pelties there will be some cooling effect of about 80 watts but it would be way too small to ever cool down a car. There is one really cool thing about this project that no one has mentioned. Instant heat in the winter time!

Re:Freon isn't used in new cars!

[BugZRevengE]

Where does the heat originally come from? All we are doing is moving the heat from inside the building to outside.
If there was no building or we opened the windows the heat would still be in the atmosphere, as the heat from the space of the building would still exist.
I will admit that if there was no building, the heat from people and computers, etc would not be there, however, if we just open a window, the heat will still exist and contribute.
All air conditioners really do is move the heat from one part of the atmosphere (in the building) to another (outside). They do generate a small amount of heat themselves, however that is minimal in comparison.

Re:Freon isn't used in new cars!

[Hard_Code]

All work generates net heat. It's not a theory. So, yeah, ANYTHING we do generates more heat, including doing work to remove heat from places we like to live in.

Re:Freon isn't used in new cars!

[palion]

I had got that. Agreed. It's not only a semantic error, it's really a syntactical one, i.e. much more fundamental.

Re:Freon isn't used in new cars!

[palion]

This is cool. I guess you did not learn how much Windows sucks while making the MCSE, you knew that before you started. This makes it even more impressive that you finished your Microsoft certs.

Re:Freon isn't used in new cars!

[julesh]

but what "400% efficiency" means in the rest of the world is "takes one unit of energy as input, and outputs four units of energy" -- i.e. free energy.

You can of course use this technique to get "free energy" (i.e. energy captured from the environment). See heating systems currently sold as "geothermal" (which aren't reallygeothermal, they just capture heat from the ground that has been warmed up by the sun).

Re:Freon isn't used in new cars!

[Sibelius]

What the hell is wrong with the world when an article claims something about 400% efficiency gets modded to +5? I'm awe-struck.

No, Virginia, there is no machine with an efficiency over and including 100%. I don't even have a clear idea of what the OP is talking about about ("efficiencies approaching 400%" -- which efficiency, exactly?), but the claim is so outlandish and against all my physics training that I'm stunned people would actually believe this stuff.

Re:Freon isn't used in new cars!

[Vlad_the_Inhaler]

I saw an article recently on Ozone depletion.

Allegedly the Ozone is returning much faster than it should be, given the rate at which the Ozone Destroyers are breaking down.

That of course gave rise to another theory, which was that massive amounts of Sulphur from the Mt St Helens had actually caused the depletion. Mt St Helens is in the US so I guess we can still blame the Americans :-)

Re:Peltiers

[Anonymous Coward]

not so sure 400% is possible, captain science....

Re:Peltiers

[USSJoin]

400% efficiency?

This seems unlikely to me, simply from a conservation-of-energy perspective. Every first-semester Physics course teaches that even 100% efficiency is unattainable in the real world; there will always be losses due to friction or whatever.

But if you've seen an air conditioner with 400% efficiency-- then why are we working for better energy sources? This would be the magical Infinite Energy Box! Let us all dance and celebrate!

Since the article seems to be AWOL now...

[kevcol]

...let's go back in the Slashdot wayback machine and laugh at the last air conditioning article.

Re:Peltiers

[HermanAB]

An aircon using vapour change effects is a heat pump. Therefore, it can move more heat, than the amount of energy consumed to move the heat.

Re:Peltiers

[ErikZ]

Maybe you mean 40%. Because the most efficient thing I've heard of is a matter-antimatter reaction, and that's 200% efficient.

Theoretically.

Re:Peltiers

[I don't want to spen]

Funny, I always thought that 4 was 400% of 1.

RSDA Press release

[mabinogi]

Here's the press release from the awards themselves, since TFA is dead.
(PDF)

easy to make

[Polymorph2000]

Get 1 thermally insulating box (with sub-divisions), 2 fans, a power supply (AC-DC), and some of these:

http://jameco.com/webapp/wcs/stores/servlet/Produc tDisplay?langId=-1&storeId=10001&catalogId=10001&p roductId=172056

and you're set. You use one fan to cool the hot side, and the other to blow air over the cold side to distribute the cold air.

If you find the right geometry for the box it might just be efficient.

The problem is the power supply from the Altenator

[GrpA]

Vapour phase airconditioning uses direct power from the engine, which often has an output of 100+ Kilowatts. More in a recent design.

No one notices a few Kilowatts disappearing. Except ricers.

Peltier devices come from the Altenator with an output capacity of around 1Kw or less, And most of that is used by Lights, Engine management etc... And for charging the battery

There's not a lot of electricity spare to run a Peltier based cooling device.

I've built something similar myself for a car once, but it only provides piped air - and didn't have to cool the whole cabin.

A 12 amp peltier device consumes a LOT of power... About 150 watts Not all cars can spare that much. And it doesn't cool much either.

I'm sorry I can't get the article up though. I really wanted to read it :(

Good on them though for experimenting :)

GrpA.

Re:Peltiers

[matt21811]

I could have made it more clear but your understanding and explanation are correct.

It is entirely possible to move 4 watts of heat energy out of the car with only 1 watt of electricity energy.

Re:Peltiers

[Anonymous Coward]

Too bad the car manufacturers can't put that extra efficiency back into the entire car. It would be great to turn on the a/c and get better gas mileage.

BFD

[Francisco_G]

I can order these out of an electronics catalog and hook them up. Look! I just 'invented' something?

Please forward to the creators

[iShaman]

Note to those high school kids: please, Please, PLEASE send one of those down the I-15 here to Las Vegas. It was 118F (50C) here yesterday...I actually watched my truck's rear-view mirror slide off the windshield!

Damn smart Utah kids...the only thing they teach our high schoolers is advanced Texas Hold'em.

Re:Please forward to the creators

[MikeFM]

Over here in Henderson it hit 122F. To damn hot.

Re:Please forward to the creators

[confusedneutrino]

Damn smart Utah kids...the only thing they teach our high schoolers is advanced Texas Hold'em.

Funny you say that. The impression several of my AP teachers had this past year was that our senior class was among the dumbest overall that they had ever seen.

*shrug*

Re:Please forward to the creators

[Thnikkaman]

I went to high school with these kids, so I'll let em know. I just got back from LA and was passing through Baker and Vegas. The temperature in Baker was 116F and when I stopped in Vegas it was 118F. The ice in my drink melted about 45 seconds after I left IN-N-OUT. I'm glad to be back in Utah where it's only 100F. Of course, we still have Orrin Hatch to deal with... :)

Re:Please forward to the creators

[otis wildflower]

Damn smart Utah kids...

So, do they win an extra wife now?

KIDDING!

Naah, now they don't _have_ to get married..

KIDDING!!!!

Re:Please forward to the creators

[iShaman]

Heh...Baker. Was there smoke shooting out of the World's Tallest Thermometer?

Re:Please forward to the creators

[calidoscope]

You'ld be better off having someone test out a huge fleet of liquid nitrogen powered cars....

Sure glad I went through LV early this month - only hit 108 then.

Re:Please forward to the creators

[Thnikkaman]

No, although I wish the thing would have burned down. The first time I passed through there I was so disappointed that the World's Largest Thermometer was a stick with lights on it. I wanted an actual thermometer. I've hated Baker ever since.

Re:Please forward to the creators

[iShaman]

Pity me, then. I love driving around Mojave Ntnl Preserve. I actually have to use that joint as a gas stop! At Baker's prices I have to eat cat food for a week to make up for it. :)

Re:Peltiers

[groman]

I've never seen one with efficiencies greater than 100%.


Oh, you haven't!? It's right here, next to my Orgone generator and universal translator.

Coefficient of Performance

[truckaxle]

It's call COP Coefficient of Performance and most heat pumps have greater than 100 percent efficiencies which depend greatly on the temperature differential between the heat sink and the air condition space. It means that it for each Watt of input you can move x watts (x being the COP) between the two thermal reserviors.

Bad Link - better one

[WindBourne]

For the naysayers, it does say that it saves some 4 MPG over current ACs. IOW, it is more efficient.

Re:Bad Link - better one

[havardi]

Of course there is no mention of how many BTUs the thing can pump. Some googling reveals that automotive a/c's are typically house-sized (30-40k btus/hr).

If this peltier cooler is anything as efficient as other peltier coolers on the market such as
http://www.melcor.com/ssspecs.html

then it would take about 11,000 watts of power to be useful (in arizona at least).

Yow!

Re:Bad Link - better one

[LnxAddct]

Yea but what temp is the cabin? I just happened to have had to work on my A/C 2 days ago and got the cabin to a chilly 46.3 F . A/C systems tend to move at least 4 watts of heat for every 1 watt of energy put in, Peltier systems, even high end ones, would have trouble moving 1 watt of heat for every 3 watts of energy. The efficiency difference is ridiculous, your moving 4 times the heat at 1/3 the energy with modern A/C systems. No way is their system more efficient unless they are barely cooling or some other number fudging.
Regards,
Steve

Re:Bad Link - better one

[Firethorn]

A problem with this is that my car's AC takes less than a MPG.

So how the heck can I get more gas milage with this system, than with no AC at all?

Re:Bad Link - better one

[Anonymous Coward]

Not to contradict the estimate, but you still need to consider the source. The 4MPG estimate comes from two high school students, albeit bright ones, who also have a vested interest in promoting their design over current versions. There needs to be independent testing, probably by auto manufacturers, before we can conclude that the new design is more efficient.

Re:Bad Link - better one

[truckaxle]

Good point. From this article

Air conditioning and/or electrical loads (headlights, heated back glass, etc.) also result in lower fuel economy (typically less than 1 mpg difference, each 10 Amps takes approximately .4 mpg).

So how are they going to squeeze an extra 4 mpg? Did the judge even check the numbers or verify the claims. I pity the poor kids who actually did their homework and got the math right but were edge out because they did not make wild ass claims.

A someone pointed out above you would need about 150 Amps at 12 Volts to provide a meager level of cooling. So using the above numbers .4 mpg/10 Amps x 150 ~ 6 MPG's. So this system would decrease the mileage significantly.

All this reinforces is the concept that fudging the math and the results can really pay off.

Re:Bad Link - better one

[jfengel]

This is why I get skeptical whenever Slashdot publishes news from something other than a major news source. Major engineering accomplishments don't usually appear first in the Salt Lake Tribune or Deseret News.

New car electrical system

[ErikZ]

Wasn't there supposed to be a new 48v electrical system standard for all cars by now?

It would allow people to hook up better electronics to their vehicle, plus it would make the car more energy efficient. The example I heard was that instead of a belt driven AC unit, it would be electical.

The article I had read at the time stated that the standard would be implemented in 2005. Does anyone know about this?

Re:New car electrical system

[zymurgy_cat]

They are moving to a higher voltage, but given the auto industry, it will probably take a while.

There is also talk of using high pressure CO2 for air conditioning systems. We're talking several thousand psi. While one may find efficiency or environmental benefits, I don't really like the idea of a system with that much pressure in my car....I've seen how US manufacturers build stuff like brake components, etc. I'd be very, very scared of something like this.

Re:New car electrical system

[Technician]

It would allow people to hook up better electronics to their vehicle, plus it would make the car more energy efficient. The example I heard was that instead of a belt driven AC unit, it would be electical.

The article I had read at the time stated that the standard would be implemented in 2005. Does anyone know about this?

The only car I know of with an electric sealed compressor instead of a belt driven compressor is the 2005 Prius. It runs off the 400 volt hybrid battery, not the low voltage side of things. They didn't bother to stop at 48 volts.

Re:New car electrical system

[Anonymous Coward]

Wouldn't an electrical AC unit be less efficient? You need to convert energy from the motor to electricity and then back into motion all of which is not 100% efficient.

Re:New car electrical system

[turbod]

How many thousand PSI are we talking?

Common rail electronic direct diesel fuel injection has been running 3000 or more PSI for several years now (I think since the first Dodge Diesel Cummins came out). All manufacturers with diesels in consumer line cars use the technology now, and I believe all Mac Truck designs use it as well.

Besides, I've never seen a blown brake line on the numerous US built cars I've seen. Not that it couldn't happen, but it would have to be a metallurgical/process failure, not a design failure.

TurboD

Re:New car electrical system

[SPY_jmr1]

Untrue: VW diesels do not use a commmon rail, but either a rotory-type pump, or a PD pump, which is unique to VW.

But yes, MOST diesels use a common rail, due to the simplicity.

Re:New car electrical system

[Solitonjoy]

Electrical is freaking great if your engine is electric or a turbine with stirling voltage ring (it has other names; magnetos is not one of them.) Otherwise of course the generator is on a belt. (Someone made a car with it on a -clutch-; a gearbox is inlined when it's in starter mode. Pricey spare, there.) There are several implementations now, in Volvos and Mercedes (european ones only!?), but the commitment is soft and the exposure of that kind of voltage is limited for obvious reasons (...for use with: http://www.powerstream.com/48v-switchmode.htm ) (plus golf carts and some solar systems) but the 1000s-strong ranks of 48v controllers and electronic accessory devices are still thin in ways. Must've been EDNmag..... http://www.edn.com/article/CA624964.html?spacedesc =newProducts Yes, I think that's our source of choice. That said, shorting your current-gen RoHS-compliant peltier across 48v instead of 12v is not going to run it in a more efficient mode. :) All good kids building efficient amperage supplies is a good thing, though. http://www.edn.com/index.asp?layout=articlePrint&a rticleID=CA624962 --Utah, Hong Kong: Fiiiiiight! 'Better' electronics though, you say: Remember when ATX power supplies didn't weigh 4 stone? A way to 'jump' a car safely at 48v while keeping voltage tolerance within 4% is its own enigma. Reusing all those old Athlon XP HSFs to condense and cool air though, is really going to help save then environment.

No ozone depletion from hfc134a either

[name_already_taken]

Freon is trademark used for a variety of nonflammable gaseous or liquid fluorinated hydrocarbons which are no longer used as motor vehicle refrigerants.

The current refrigerant, hfc134a contains no chlorine (the ozone damaging part of R12) and has an ozone depletion potential of zero.

The idea of using Peltier devices is interesting, because there'd be no mechanical parts to wear out, or refrigerants to leak out, so the system should be much more reliable, but I thought Peltiers would require a huge amount of current to do as much cooling as a car A/C system delivers.

Re:No ozone depletion from hfc134a either

[alienw]

I thought Peltiers would require a huge amount of current to do as much cooling as a car A/C system delivers.

The car's electrical system is not suited to supplying significant amounts of power. A typical alternator tops out at about a kilowatt of power (80A or so). Due to the low voltage, ridiculously large currents are necessary.

Of course, a peltier is much less efficient than a compressor system. A compressor typically has a coefficient of performance (COP) of around 3, meaning that it removes 3 units of heat for every unit of supplied work. For peltiers, this value is around 0.4, which is a huge difference. Thus, the peltier would consume about 7x more energy to supply the same cooling capacity. This is the main reason cars don't use peltier A/Cs.

Re:No ozone depletion from hfc134a either

[UniverseIsADoughnut]

Yeah, I think people are missing simple facts here.

Pelters aren't very efficient.

Furthermore, if they were a good means of cooling things, we would use them for everything, but they don't thus why some kids build it, and corporations don't. If would be massively cheaper for them to use and have nothing but benefits. But they suck for the job, thats why they don't use them.

But people seam to be missing that part of this thing. I'm guessing all the articles are gone cause someone pointed out how bad a story it was.

Re:No ozone depletion from hfc134a either

[mrchaotica]

Here's the weird thing though: according to TFA, people who ought to understand this (such as the ones from the EPA and Ricoh) think that it is more efficient than normal phase-change A/C. How can that be?

Re:No ozone depletion from hfc134a either

[gbulmash]

Due to the low voltage, ridiculously large currents are necessary.

I don't mean to contradict someone who knows more about electronics than I do. I took one year of elementary electronics in high school and then went into creative pursuits that required less math. But if a car's battery & electrical system run at 12 volts, 80 amps creates just short of a kilowatt.

Given that other systems in the car draw current, the system won't get a full kilowatt, or maybe not even half a kilowatt.

As I said, I went into creative pursuits which required less math, so I can't do the calculations on how many BTUs a Peltier cooler can exchange. And the following is just back-of-envelope calculation based on bits and pieces I've picked up, so excuse me for any inaccuracies: I know that a 6,000 BTU window AC unit can cool around 900 cubic feet pretty well, and I know that the interior of your average mid-size sedan is maybe 150 cubic feet at most, so the Peltier AC would need to rate at around 1,000 BTUs.

Can a Peltier system, with a COP of 0.4, turn 200-300 watts of power into 1,000 BTUs or more of heat exchange?

- G

Re:No ozone depletion from hfc134a either

[Eivind]

The volume of air in the car is only marginally interesting when calculating the needed cooling.

To keep a car cool, the AC has to remove the same amount of heat as are being added by the sun/outside temperature, persons in the vehicle etc. Plus a bit so that it'll be capable of *cooling* the car and not only capable of *keeping* it cool.

The average house does not consist of single windows and uninsulated metal all around. A typical house is insulated, which works just as well in keeping heat out as in keeping it in. The average car is not. (or very little)

100BTU/hour is about 293 Watts (like so many nonmetric units, BTU is poorly defined, it's value varies somewhat depending on temperature), so a system with an COP of 0.4 would need to consume 293/0.4 = 732W to cool that much.

This is certainly possible, but it's a lot of power for a car, at the voltages used you'd need more than 60A.

A compressor-cooler with a COP of 3 on the other hand will require about 100W, which works out to around 8A.

Perhaps there's a reason why this is the solution used by all current auto-makers ?

Re:No ozone depletion from hfc134a either

[Kadin2048]

Maybe we're missing something: like this is going to be a special air conditioner, specifically designed for the high Arctic...?

Seriously, the only way I can imagine they even got this thing to work, without throwing an extra gasoline generator in the trunk of the car, is to build it with a much smaller cooling capacity than a standard phase-change air conditioner. Which is stupid; the car companies don't make A/C units bigger than they have to be just for fun, and given how much Americans like air conditioning, I doubt anything smaller would be marketable anyway.

Re:No ozone depletion from hfc134a either

[Descalzo]

I heard that in the near future they were abandoning the 12V battery in favor of 24V. Would that make enough difference?

Re:No ozone depletion from hfc134a either

[alienw]

Well, not to mention that in most cars the compressor is just hooked to the engine drivebelt with a magnetic clutch, so you don't need a more powerful alternator or a motor to drive it. Although some high-performance cars do run it off the alternator to save on friction when it's turned off.

Re:No ozone depletion from hfc134a either

[rogerzilla]

With the power requirements of a large a/c compressor - you'd still need thick cables (I'm not sure how the Prius does it). With 24V you'd have more problems with damp circuits; 24V can electrolyse dirty water, 12V can't.

Re:No ozone depletion from hfc134a either

[alienw]

If you actually understood what the article was saying, you would have noticed that the only thing mentioned was that EPA might have expressed interest. It never says they even looked at it. As far as Ricoh, they won the competition simply because Ricoh liked the project, not because it's a workable idea. You think they have engineers sitting there evaluating project proposals?

The only efficiency figures in that article were some rough estimators from the students, but I really doubt they know enough of the relevant physics and thermodynamics to estimate efficiency correctly. It doesn't take much brains to stick a peltier to a couple of heatsinks and call it an air conditioner. It's considerably harder to measure its efficiency and compare it to that of a car system.

Re:No ozone depletion from hfc134a either

[alienw]

12V electrolyses water just fine. You prevent it by sealing the connectors. The Prius uses something like 96V or more for its engines and probably steps it down for some of the accessories and such.

Re:No ozone depletion from hfc134a either

[penguinboy]

Doesn't really matter, it's still the same amount of power. Going to higher voltages just means smaller wires and less loss.

Re:No ozone depletion from hfc134a either

[JLF65]

So they won an award... big whoop. That only means that a couple judges (who probably weren't scientists by the way) thought it was better than the other exhibits. Maybe this was an off year. Second, no one said it wouldn't work, just that it's less efficient than the standard mechanical AC.

You ignored a lot in TFA yourself. The only people they interviewed for TFA were the two boys and their physics teacher from high school. No "scientists" were quoted in TFA as saying their project was in anyway good. Second, being able to blow cool-feeling air inside an air-conditioned hall for a few minutes is NOT the same thing as keeping a black car cool for several hours on a 110 degree day in sunny Arizona.

First, TFA says these boys nearly flunked because strapping a hair-dryer to five peltiers bought from eBay took all their free time for more than two years. Second, there was no mention of the massive heat-sinks and fans needed to cool the peltiers. If you were an electrical engineer, you'd know that peltiers have a hot side and a cool side. Failure to cool the hot side results in a loss of efficiency, an increase in current consumption, and a higher temperature on the cool side. Ever looked at a peltier CPU cooler? It has a big honking heat sink and fan to cool it. Just as a peltier CPU cooler has trouble working in a room with >90 degree ambient temps, so would the boys' peltier AC.

No, winning a prize at a fair is not a sign that a project is any good, much less useable in real life situations. This idea of using peltiers to cool a car is not even new, much less a "breakthrough invention." As others have pointed out, this was rejected by car makers decades ago as too inefficient. How can you "invent" something that was considered and rejected decades ago? TFA is just playing up the story more than it should because it's a couple of local boys who won a prize. Small papers always overblow local accomplishments.

Re:No ozone depletion from hfc134a either

[NateTech]

E=I/R (Ohm's law)

Double the voltage, half the current if resistance stays the same.

Re:Peltiers

[non0score]

I think efficiency means the conversion from one form of energy to another (that is not heat, otherwise the discussion is kinda pointless). Going from heat to electricity is one such example. So, converting 40kJ of heat to 20kJ equivalent of electricty with 20kJ still in heat means 50% efficiency. Technically, matter-antimatter reaction is 0% efficiency, since all you get is heat (in the form of photons). But do correct me if I'm wrong.

Re:What an ironic twist.

[B4L1STA]

1) It's spelled "Mormons"
2) The trib moves the URL after it's no longer in the day's news
3) The trib isn't a Mormon paper. The Mormon paper is Deseret News (www.desnews.com)

But I have to admit, the poor Trib probably isn't used to getting slashdotted :)

In today's society...

[dpdawson]

More efficient?
Last longer?
Better for the environment?

It'll never catch on.

Re:In today's society...

[$RANDOMLUSER]

Yeah, and those Peltiers would be even more efficient if they didn't have those Athlons strapped to them...

Re:In today's society...

[lightyear4]

It would catch on if such things ever made it into the mainstream. There are plenty of examples of companies buying and burying patents that would be otherwise helpful.

Re:In today's society...

[Anonymous Coward]

Why the hell is this modded 'insightful'? It's not even very funny as a joke.

Re:Peltiers

[calidoscope]

Modern air conditioners have energy efficiencies approaching 400%.

Ummmm, I believe the term you want to use is "coefficient of performance" - which is how many watts of heat are transferred per watt of electrical power used. Also called an energy efficiency ratio.

Having said that, your point about the relative efficiencies of mechanical refrigeration units vs Peltier effect devices is correct. I have a ~18 cu ft fridge in my garage that uses less energy than a 1 cu ft Peltier cooler. Another point, the main focus for the development of Gadolinium refrigeration was to replace Peltier effect devices for small scale refrigeration needs.

Re:Peltiers

[arch_avaj]

Hmm, just reading my physics textbook a few hours ago about this topic, so I can clarify the obvious mistakes.

AC's have a Coefficient of Performance (COP) around 4-5 (or 400%-500%)
This is similar to effiency, but obviously not the same.

COP of a cooling device is measured as:
(Energy Removed from Cold Reservoir) / (Work Done on the device)

AC's don't cool, they just move the heat, and moving the heat doesn't require a lot more energy.

If this new device has higher efficience, it will have a similarily higher COP.

hey!

[austad]

I built one of these back in 1999 with some peltiers I ordered direct from a manufacturer, some old heatsinks, case fans, and bent tin sheets.

It fit in the window, just like a regular ac unit, but it didn't stick out at all. Basically, it was just two layers of heatsinks with the peltiers sandwiched in between. The hot side faced out the window and fans forced air on them to cool them, and the cool side faced inwards, with fans along the lower edge, a sheet of tin across the middle to make the air flow more over the fins, and an opening on top where it blew into the room.

It worked well for a small room. I suppose if I had the money at the time, I could have purchased some massively power hungry units and been able to get some crazy cooling power out of it. I probably still have it in a box somewhere.

Re:hey!

[austad]

Actually, I bought a power supply from here:
http://www.ax-man.com/

It's some long skinny thing, and puts out something like 800 watts. The peltiers I was using only drew about 40 watts each, and there were 12 of them. So I had plenty of power to spare. I originally bought it to build a cable lighting system in my apartment using a bunch of 50W low voltage halogens, but I could never the sockets I needed to plug the lights into and cannibalized it for another project. :)

Article already pulled...

[pongo000]

Here's the Google cache...

(Don't need karma points, so don't waste them here.)

Re:Peltiers

[layer3switch]

At least, IMHO, I don't believe, those two kids were to compete against hightech MIT/CalTech graduates. The idea itself is what is the most important thing here, not the technology of their choice.

Environmentally conscious education and kids inspired by the teachings to apply their talents and knownledge (no matter how inefficient or outdated that may be) in order to make a better devices, those are economically and environmentally friendly.

I think, that's enough to award their talents and invention. I, for one, would like to see more kids "applying" their telants in such manner.

ownare

[Qnaal]

wikipedia was owned for a while there...

byproducts

[ashridah]

Wait... aren't there really nasty byproducts from the construction of solid-state stuff like peltiers?

I know that there's some horrible chemicals used in the production of sillicon wafers (including solar cells, generally, iirc), but is the situation the same for peltier devices?

ash

Re:The problem is the power supply from the Altena

[RzUpAnmsCwrds]

"Vapour phase airconditioning uses direct power from the engine, which often has an output of 100+ Kilowatts. More in a recent design."

Not necessarily. The Toyota Prius, for example, uses an electric (144V AC) A/C compressor. Of course, it's the exception, not the rule. The Prius has a high-voltage battery system and a powerful inverter.

"A 12 amp peltier device consumes a LOT of power... About 150 watts Not all cars can spare that much. And it doesn't cool much either."

True. 150W is a lot to ask of a typical car. But a hybrid vehicle, like the Prius, can put out 5+ KW continuously without breaking a sweat.

"Good on them though for experimenting :)"

Well, if they have developed a peltier system that rivals an electric-powered vapor-phase system in efficency, their technology could very well find its way into future hybrid vehicles.

Neither better nor new

[HermanAB]

Peltiers are not new and are less efficient than a vapour change heat pump. It sounds like a Microsoft innovation... (I should get an award for dragging Microsoft into a discussion on airconditioners!).

Re:Neither better nor new

[Radworker]

Oh, I don't know about that. It seemed logical to me that Microsoft would come up. Weren't we talking about vapour vs . . . ?

Bad pics at wilki

[bxbaser]

Certainly isnt what i was expecting

Re:The problem is the power supply from the Altena

[mogalpha]

Seriously, Peltier devices are known for their inefficiency; way worse than what most A/C's now use. I have no idea why they got an award for this; yes, Peltier cooling is a lot of fun, and yay for solid-state and environmentally-friendly contraptions, but as many have already stated, Freon's gone the way of the dinosaur in most new cars (definitely all here in the States), and the greater wattage translates directly to wasted gaoline, something people won't be too happy with if you consider the long run.

Re:Peltiers

[RRRussian]

And here I was thinking that all AC's were full of hot air...

Re:The problem is the power supply from the Altena

[Frank T. Lofaro Jr.]

If no one notices a few kW disappearing due to A/C load other than ricers, than why do all modern cars disengage the A/C clutch when you go wide open throttle?

If you push the pedal to the floor with the A/C on you'll get your performance, at the cost of warmer air until you are done.

1998 Ford Expedition

[green pizza]

Cars sold in the states haven't used Freon since the late 90's. That's why A/C sucks in cars now.
Then why does the A/C in an un-modified, one-owner 1998 Ford Expedition (which was manufactured long after the R-12 ban) blow HUGE amounts of ice cold air?? That vehicle has the hardest, fastest, coldest A/C I have ever felt. Even colder than a 1975 Cadillac Fleedwood (the original freezer on wheels).

Re:1998 Ford Expedition

[ppanon]

Because if you own a Ford Expedition, power train load and poor mileage are not a concern.

Re:1998 Ford Expedition

[Fulcrum of Evil]

Go get a Subaru Legacy - it blows ice cubes in the frickin desert.

Re:1998 Ford Expedition

[green pizza]

Because if you own a Ford Expedition, power train load and poor mileage are not a concern.
It's not mine, but I wouldn't mind one, I can live with 16 - 19 MPG.

Re:1998 Ford Expedition

[spun]

My '05 Subaru Imprezza does a damn good job here in Albuquerque. It takes about 5 minutes to completely cool the car when it has been sitting in the sun all day, and it's been over 100 during the day here recently. The air coming out gets cold in about 30 seconds. And I have never seen the engine temperature vary at all after it hits operating temperature, no matter what the conditions.

not as efficient...

[YesIAmAScript]

Peltiers do not work very well and are not as efficient as a phase-change (freon-type) system. You can prove this to yourself by buying a Peltier-based portable cooler at Target (they've been available for 20 years, search for "coolerator") and a $99 phase-change based cube fridge. The Peltier can barely get a six-pack to 35 (F), the cube fridge can make ice in a 1+ cubic-foot space.

This is just total bunk. The only way it saves energy is by not cooling as much.

Honestly, I think that the only threat to phase-change systems in small systems is sonic cooling. It could be more efficient, require less maintenance and have less environmental impact than a phrase-change system.

Evaporative systems are nice too, especially for large installations, but don't work for getting much below ambient.

Re:not as efficient...

[Punboy]

Ok, but your cube fridge is a) insulated, b) cooling an enclosed space, and your "coolerator" is a) not insulated, b) trying to cool a much larger space.

Re:not as efficient...

[TRRosen]

yeah but the coolerator is most likely rated around 40W while the mini fridge is 200+. Simply put no one has really tried using peltiers in a larger device than the little toys like these.

Re:not as efficient...

[stienman]

That was a bad analogy.

The power consumed by your $99 fridge is an order of magnitude larger than the power consumed by your $40 target peltier cooler.

Look up the tech specs and see for yourself. The smaller unit takes less than 120 watts, then larger unit takes more than 600 watts (depending on the $99 unit you choose, it'll take much more than 1KW).

-Adam

damn editable encyclopedias

[5n3ak3rp1mp]

I don't know if anyone has noticed yet but the wikipedia entry to the peltier effect linked from this post is now headed at the top with two images, a poo and a peenie (as my 6 year old nephew would call them). Um....

You have no idea what a peltier is...

[Cyno01]

Do you?

Re:Peltiers

[Trogre]

If your goal is to generate heat, then yes you're right. But that's not what we're talking about.

Efficiency is a measure of how much useful energy you get out of a system compared with what you expend in doing so (contrast that with efficiacy).

Going by this a bar heater is 100% efficient, since any energy lost in the cable, etc is radiated as heat, which is useful energy for the purpose of heating a room.

Now heat pumps usually consume electricity to move heat from one sink to another. Once the cycle is started, the useful energy that is transferred is much greater than the energy you're expending to drive the pump. Therefore you're getting more energy out than you're consuming.

By consuming I of course mean converting energy from one form to another. And no this does not violate principles of thermodynamics since we're not converting the heat into another form.

cool things about this idea

[TRRosen]

1. works with electric cars

2. unit can be in passenger area and not in engine compartment

3. you could have several small units instead of one big one

4. flip the peltiers and you have a heater

5. no pulley being spun even when not in use

6. should be much lighter (although alternator would get bigger)

Re:cool things about this idea

[TRRosen]

actually

4. change polarity and you have a heater

Re:cool things about this idea

[walrusx]

It is fairly rediculous to suggest that an internal combustion engine would have a use for an additional heater. One argument I feel qualified to argue against.

Re:cool things about this idea

[Forbman]

Unit will still be in engine compartment, right next to the heater core, just like the AC cold exchanger is right now. Except rather than having to run the AC compressor, you just have a beefier alternator, which will probably weigh a couple of pounds less than current alternator+ac compressor. Plus, the hotter air from the hot side has to go somewhere, and the engine compartment is the most convenient place for this, as the fan is already there pushing air through the engine compartment when the car is not moving.

Oh, and instant warm (not hot) air in the winter, too.

Don't need to flip the peltiers to reverse the effect, just reverse the polarity going through them (like my two thermoelectric coolers do...).

Re:cool things about this idea

[Sir_Real]

4. flip the peltiers and you have a heater

Is this heater instantly hot? Do you have to wait for the engine to get warm before you do? If you don't, then this would be great in cold climates. I've wasted a lot of gasoline waiting for my car to get warm enough to sit in.

Re:cool things about this idea

[Fizzl]

Actually, nowadays turbocharged diesel vans need additional heater in extreme conditions. ..Extreme, as in 8 months of a year in Finland.
This company seems to be so much de-facto supplier of these heaters that usually car fuel heaters are called Webasto's. At least in here.

Re:cool things about this idea

[artemis67]

Well, if you could reverse the polarity through the chips to produce instantly warm air during the winter, that would be huge. And just have the Peltier chips switch off once the engine core reaches a certain temperature.

Re:cool things about this idea

[phorm]

3. you could have several small units instead of one big one

There's an idea, having specialized units would allow you to place peltiers by the various sections of the car... front/rear left/right... allowing for more customized air temperatures.

Re:cool things about this idea

[SnarfQuest]

1. works with electric cars

Add an electric motor to the compressor, and so would a compressor.

Electric cars need all electronics to be very efficient, otherwise you lose a lot of distance. Going from a cooling/cost of 4 to 0.3 is going to be a major hit on milage.

2. unit can be in passenger area and not in engine compartment

Just what everyone wants, less leg room.

3. you could have several small units instead of one big one

With less efficiency too. More ducting for airflow and waste heat removal, more cabling, additional fans, more weight, more volume. Less legroom.

4. flip the peltiers and you have a heater

Just change the polarity.

5. no pulley being spun even when not in use

So what? How much energy does a spinning pully use. Probably less than a second (or larger primary) alternator would.

6. should be much lighter (although alternator would get bigger)

The alternator would need to get MUCH bigger to get the equivelent cooling power. Either that or a second alternator (remember your idle pully concern).

Instead of driving directly a 400% efficient machine off the motor shaft, you now drive a 3% efficient device off a ?95% efficient alternator which is also driven off the shaft.

Re:cool things about this idea

[TRRosen]

Actually the figure I have from engine builders is that the pulley/clutch drains about 2 Hp thats over 1400 watts that makes the first 2000 btus of cooling free. Considering the clutch's draw is always there, its easy to see how this could have a dramatic effect on the real efficentcy of the system.

note-- car systems can draw up to 20hp or 15,000 watts this is more then 10 times that of a household window AC unit.

main lesson here AUTOMOTIVE AC UNITS ARE VERY INEFFICEINT were talking EER of less than 1 here.

Re:Show Prior Art and Beat Them To The Patent!

[StarsAreAlsoFire]

he might be able to break the patent, but he wouldn't be able to get his own. Been in use for over a year, it can't be patented.... I think... not totally positive on that.

wtf

[HiddenCamper]

why did someone put a penis on the wiki page?

Re:wtf

[joelsanda]

why did someone put a penis on the wiki page?

That's not a penis, it's a picture of Deep Impact!

Just roll down the windows

[Andrew Tanenbaum]

And if you're still too hot, drive faster

Re:Just roll down the windows

[Andrew Tanenbaum]

Interesting, I suppose fans are ineffective when the ambient temperature is warmer than your body temperature. Yuck!

don't think of it as removed

[YesIAmAScript]

It's moved, not removed. A/C moves heat from one place to another. The energy it takes to do this is actually all just lost as heat and works against you if exhausted in the wrong place.

It is easy to move more energy than you consume. A Peltier can't do it, but a phase-change A/C can do it many times over.

If A/C actually REMOVED heat, it would be putting energy back into the wall through the plug. It doesn't do that.

Mean and bitter...

[Marvin_OScribbley]

Like this?

Re:The problem is the power supply from the Altena

[Loualbano2]

Couple of clarifications/corrections.

1 hp = 746 watts

While you are technically right about the 5+KW its more like 50KW at least, and that would only be 67hp so it's probably closer to 80-100KW.

12A is not much for a normal car. Most modern cars have 80-100A alternators, depending on options like power seats, seat heaters, etc. Car Audio hobbyists routinly install 150A+ alternators on normal cars. Some folks will run two if needed.

-ft

Re:Peltiers

[onya]

for a reverse cycle aircon in heat mode, this is true. most cars use the engine coolant pumped through a heater box for heating. aircon is cool only.

Re:The problem is the power supply from the Altena

[sam_da_mann]

But then the A/C switch wouldn't double as the Turbo button.

If the patent holds up

[lheal]

They could be gozillionaires.

We have a GE thermoelectric water cooler. It works great. The water's not as cold as a regular refrigerator puts out, but the 5-gallon bottles are hard to fit in the fridge.

I just hope Kevin McBride isn't handling the patent. He's got an interest in IP law, you know. His brother Darl would end up suing GE.

Re. Whatever ...

[Tjp($)pjT]

The new stuff is r-134.
The chips are semiconductor chips that when current is applied exhibit the peltier effect. One side gets warm, the other cooler. Essentially a solid state heat pump. No compressor, no liquid refrigerant needed. Instead just blow air over the device and its "cold sink" (same essentially as the expansion side air handler for a liquid refrigerant system in principle). So fewer moving parts. Especially the blasted compressor clutch assembly which in some cases makes it cheaper to replace the whole compressor with a rebuilt one than separate the clutch from it. The clutch causes the pulley to spin freely and not drive the compressor when cold is not demanded by the air temp controls, hopefully thermostats, but n ot always in cars.

in your disk drive analogy, it would be like coming up with a cheap flash drive that beat the specs for lifetime and cost to those spinning magnets you mentioned. It makes it last longer by eliminating wearing spinning parts that rub against each other roatating and moving up and down and up and down ... Not sure how the parent was maked "insightful" but there is no "lacks relevant technology background". Seriously though it is fascinating technology and along with heat pipes makes overclocking much less of a mess.

Re:Re. Whatever ...

[Helter]

"in your disk drive analogy, it would be like coming up with a cheap flash drive that beat the specs for lifetime and cost to those spinning magnets you mentioned"

Yeah, it would beat the specs for lifetime and cost, but it would require 100 watts of power to operate.

OT: Re:wtf

[NBarnes]

Surely you're not shocked to learn that there are people who cannot build up, so to fill the void inside they tear down?

It's the basic distinction between civilization and barbarism. The person in question is one of the huge number of people on the Internet that, in the great struggle between those who wish us all to be richer and those who wish us all to be poorer, have decided they're on the side of those who wish us to be poorer.

Re:Peltiers

[StarsAreAlsoFire]

Any time you create a heat gradient you are creating useful energy. Now, if you only consider tossing an antimatter baseball at the moon, sure, it could be argued that you can't get energy out of that. But if you direct the energy into a pool of liquid, then use the gasses/high pressure steam created to spin a turbine.....

etc etc.

Cheers,

Re:Bad Link - better one No Just Bad Science

[truckaxle]

The students' research estimates their system would cut millions of pounds of hydrocarbons and nitrous oxides, and billions of pounds of carbon monoxide found in vehicle emissions. It also would increase gas mileage by four miles per gallon and hike horsepower by as much as 4 percent -- saving American drivers billions of dollars in annual gasoline costs.

Since when do they hand out awards for bad research at best or out-and-out lying. A peltier effect heat pump has a COP of around .3 and a typical R134a vapor compression AC has a COP of about 4. In other words, the existing AC systems are an order of magnitude more efficient. Now how are they going to increase the mileage by 4 and add more horsepower?

They would have to increase the size of the alternator several times to power this a peltier effect heat pump and you would have the unavoidable inefficiencies of converting mechanical energy into electrical to boot.

Why didn't they just mention that this thing runs off of cold fusion - and maybe they could get the University of Utah to endorse it ;(

"can't tell"?

[SuperBanana]

No one notices a few Kilowatts disappearing. Except ricers.

I'm sorry, but you're completely full of shit. Every time my A/C compressor clicks on while I'm driving, I can tell; I drive a manual, and if I'm paying enough attention, I can tell especially if revs are low (ie 2k).

Vapour phase airconditioning uses direct power from the engine, which often has an output of 100+ Kilowatts.

You are making the assumption that the engine produces its power evenly across the band, which is outright garbage. Most engines make much more horsepower at high engine speed; better engines tend to keep making that power the closer they approach redline (at high engine speeds, resistance in exhaust and intake paths kills horsepower because volumetric efficiency drops).

The engine will not make NEARLY as much power down at ranges people typically use; ie 2000 to 3000 RPMs. Example- the current Ford Mustang engine (no, I don't drive one- just the first chart I could find) makes 250HP at 5,000RPM+. At 2,500 RPM, it makes 100HP. The chart started at 2,500; numbers probably drop to 50HP at 2000. Suddenly, an AC compressor that uses several HP becomes a two-digit percentage of total engine output. While humans suck at absolute measurements, we can be -really- good at picking up on the finest relative differences.

Also, maximum claimed horsepower is often under ideal circumstances; ie cool air temps, engine cold/warm not at full operating temp, lightweight oil, and at sea level. It's also always on a perfectly functioning engine; ie fresh air cleaner, ignition bits are all new, perfect compression in all cylinders, etc.

Re:"can't tell"?

[GrpA]

>>No one notices a few Kilowatts disappearing. >>Except ricers. >I'm sorry, but you're completely full of shit. >Every time my A/C compressor clicks on while >I'm driving, I can tell; I drive a manual, and >if I'm paying enough attention, I can tell >especially if revs are low (ie 2k). That's because you're a ricer - I can tell from your response ;) (Tongue in cheek) Heh. Don't take that seriously. I'm not trying to start a flame war. And I apologise if you took exception to my generalisation. I'm quite familiar with HP and power ratings. AFAIK, the compressors are most efficient at low RPM, when there is plenty of torque available, so the effect would be even less.... However, for the sake of a quick post to an audience in which probably only about 1% of readers understand the relationship between torque, power and rpm, I thought I'd simplify. As for my experience and background with cars? Have a close look at my alias. GrpA.

Re:"can't tell"?

[Anonymous Coward]

No one notices a few Kilowatts disappearing. Except ricers.

I'm sorry, but you're completely full of shit. Every time my A/C compressor clicks on while I'm driving, I can tell; I drive a manual, and if I'm paying enough attention, I can tell especially if revs are low (ie 2k).

this could be a sign that you're a ricer...

Re:"can't tell"?

[Lumpy]

dude, your headlights use more power than the air conditioner in a modern car.

Turn off your headlights and your foglights (driving with them on makes people look like a dorks anyways) and you will have more than enough power restored for the AC.

My econobox that get's 42mpg went up to an average of 43mpg when I disabled the Daytime Running lights that was simply a diode that was turning on the headlamps when the car was running.

granted i drive highway speeds 909% of the time, but ther are many more power hogs in your car that are drawing more than the airconditioner does.

Re:"can't tell"?

[Vraeden]

"Turn off your headlights and your foglights (driving with them on makes people look like a dorks anyways) and you will have more than enough power restored for the AC."

Safety is more important than fashion. I'd rather see people drive with their lights on all the time than never (as they most often do).

Re:"can't tell"?

[gillbates]

dude, your headlights use more power than the air conditioner in a modern car.

Um, dude, you're wrong. Ford claims that the air conditioning compressor alone will use 25 HP on a hot day.

Your headlights, OTOH might use 10 or 20 amps. At 13.5 volts, thats 270 watts max. Or about 1/3 of one horsepower.

Re:"can't tell"?

[illumin8]

My econobox that get's 42mpg went up to an average of 43mpg when I disabled the Daytime Running lights that was simply a diode that was turning on the headlamps when the car was running.

I call BS. My car has Xenon HID lights plus foglights and I get no noticeable difference in gas mileage whether I drive with them on all the time or off. And because my car has auto-off headlights that stay on for 30 seconds after I turn off the vehicle, I leave them on all the time. It's safer, and other drivers are more likely to notice you're coming at them if they're on. You're foolish if you manually disabled your daytime running lights. They are probably only 15 watts per bulb (x2) and there is no physical way that this small amount of draw off your alternator will affect your gas mileage in a noticeable way.

Re:"can't tell"?

[silicon not in the v]

dude, your headlights use more power than the air conditioner in a modern car.
Turn off your headlights and your foglights (driving with them on makes people look like a dorks anyways) and you will have more than enough power restored for the AC.

Where is the moderation for "Wrong"? Lets say that in one case, you were to drive with basically none of the electrical features in your car running. Then turn on your headlights, dome light, reading lights, windshield wipers, fuzz buster, and the radio on really loud. Wow, I'll bet your car feels really sluggish now, huh? It doesn't? Oh yeah, that's because those things don't take much power, and that power comes from an alternator which is always running and generating at least as much power as is needed to run all of the electrical accesories in your car. In a smallish car, when you turn on the A/C, you'll feel that sudden drag like somebody latched a tow chain onto the back.

Re:"can't tell"?

[reidconti]

HID lights use less power than conventional lights. 35w or so, versus 55.

Then again, DRLs use about 35 I think...

Re:"can't tell"?

[illumin8]

HID lights use less power than conventional lights. 35w or so, versus 55.

Then again, DRLs use about 35 I think...

Even with a power draw of a few hundred watts, I doubt you'd see an appreciable MPG difference.

Re:"can't tell"?

[modecx]

No way... Lights are limited to 50-60 watts each. AC systems pretty well need to be in the multi-kW range to be at all effective in a car. There's lots of single pane non-coated windows, hot metal, etc. Etc. that you have to deal with, plus people would be pretty pissed off if their air wasn't insta-cold.

It's not like a house where you can take a 1kW window AC unit and cool a small room over the course of the whole day.

Re:"can't tell"?

[muckdog]

Sorry but I'd have trouble believing that you can measure your mpg accurate to 1mpg with the gas pump gauge and odometer as your sources. There's too many other factors (temp, air pressure, tire pressure, when the pump cuts off, etc. ) to be scientifically that accurate.

Re:"can't tell"?

[HardCase]

Not to nit pick, but diesel locomotives use electric motors to drive the wheels. The diesel engine drives generators. The US M1 tank uses a gas turbine engine.

Both, though, do have great air conditioning systems!

It's Actually 42v

[mrdrivel]

The new standard calls for 42v not 48.

It looks like there is the Toyota Crown Royal which uses 42v and a "new SUV from GM" that will use 42v as well. Source.

Re:It's Actually 42v

[ArtStone]

If the ieee was involved, why didn't they go metric and make it 100 volts?

Re:Peltiers

[Team Zissou]

AC's don't cool, they just move the heat, and moving the heat doesn't require a lot more energy.

Consider a horizontal cylinder sealed at each end with a piston in the middle which can move freely up and down the cylinder. There is ONE perfectly elastic particle in the left chamber and ONE in the right chamber. The one in the left bounces around at say v1 m/s (cold particle) and the one in the right bounces around at say v2 m/s (hot particle, v2 > v1). The two particles will shift the cylinder to a point where the (average) forces on each end of the piston are equal and opposite.

Now apply an external force on the piston (via an external lever or magnet) so the piston moves from the hot end to the cold end at speed V. The cold particle bounces off the piston at speed v1 + 2V (thereby heating up) and the hot particle bounces off the piston at v2 - 2V (thereby cooling down). We therefore have a refrigerator or air conditioner and can easily work out the heating power or cooling power in terms of the external mechanical power, with the result that cooling power > mechanical power for appropriate values of V and chamber length.

Re:Peltiers

[gerardrj]

I think what's being referred to is the heat the unit moves vs the heat it generates. Refrigerant based units rely on phase change of matter (gas to liquid to gas...) which requires the absorption and release of tremendous amounts of energy. The poster was not trying to say that the compressor was not wasting any energy as heat/noise/vibration.
If I recall my physics even somewhat correctly, the amount of energy it takes to convert a gram of water at 32F from solid to liquid state is 80 calories. That same amount of energy will then increase that same gram of water from 32F to 176F.

Stirling engines as heat exchangers?

[otis wildflower]

I wonder if Stirling engines could be used to convert heat from, say, HVAC coils, into usable power for a car? Or as an add-on to a turbo intercooler?

Fridge ?

[Bugmaster]

Thermoelectric refrigerators utilizing this same effect have been on the market for a while now. The original site is toast, so I can't quite figure out: how is this new invention any different ?

Great! Here's why it won't happen...

[borgheron]

It won't happen because it will put the current freon industry out of business. We're talking jobs here people. And since when has progress ever stopped us from propping up a failing business model before?

The freon manufacturers will lobby congress to have the new invention tied up in a mess of approvals and tests and other some such things that by the time it makes it to market it will be so expensive no one will ever want to buy it.

If it makes it to the market at all. And when it does, the freon manufacturers will again lobby to have it declared unsafe, or worse, unamerican to use Peltier-effect based air conditioners.

Cynically yours, GJC

The Official R-12/R-134a/Freon Thread

[DasBub]

Let's set the record straight, here.

The noun "Freon" has a double meaning. Strictly speaking, it is the trademark name of refrigerant R-12, a single product of a specific formulation.

Due to its popularity it has become a sort of catch-all term used to describe an entire family of products. Much the same way that all couches can be called Chesterfields or all tissues can be called Kleenex, Freon can be used to describe a family of refrigerants.

As well all know, the actual Freon refrigerant, R-12, has been banned for a decade now. In this way, it is proper to say that no air conditioning unit in the US, Canada, etc., made since 1995 uses Freon.

The currently widespread refrigerant is R-134a, trademark name "Suva". It's chemically different from "Freon", but can be described as being part of the Freon family. This can make casual discussions a bit muddled as everyone argues whether or not Suva is Freon... Well, maybe I'm the only one having that type of casual discussion...

So, to make a short story long:

Freon is a Freon, Suva is a Freon, but Suva is not Freon. Got it?

Re:The Official R-12/R-134a/Freon Thread

[MooseMuffin]

Ive never even heard of a Chesterfield. \troll

Re:The Official R-12/R-134a/Freon Thread

[Luckster7]

Freon is a Freon, Suva is a Freon, but Suva is not Freon. Got it?

You mean like:
Linux is a Unix. AIX is a Unix, but Linux is not AIX.

Got it.

Re:The Official R-12/R-134a/Freon Thread

[kfg]

Well, maybe I'm the only one having that type of casual discussion...

Nah. I've had this very one here on /. already. Everything's a dupe here, even my own bloody comments.

KFG

Re:The Official R-12/R-134a/Freon Thread

[kfg]

Well, maybe I'm the only one having that type of casual discussion...

Nah. I've had this very one here on /. already. Everything's a dupe here, even my own bloody comments.

KFG

P.S. And it's rather ironic that I have to add this very line to evade the dupe filter.

Re:The Official R-12/R-134a/Freon Thread

[MisaDaBinksX4evah]

Linux is a Unix. AIX is a Unix, but Linux is not AIX.

Wait a second. Linux is Posix-compliant, but it's not Unix (I realize there are people who might argue otherwise, but I'm going with the commonplace view here). And I don't see how "Suva is a Freon" either. That's like saying "nylon is a rayon" or some other nonsense.

Re:The Official R-12/R-134a/Freon Thread

[Tim C]

How about, argon is a noble gas, xenon is a noble gas, argon is not xenon?

Re:The Official R-12/R-134a/Freon Thread

[johnny cashed]

Freon is actually a whole family of DuPont CFCs. I know because on the farm we used an old 30 gallon drum (not gas bottle) labeled "Freon" that we stored diesel in. R-12 could not be stored in such a drum as its vapor pressure would blow it out. Freon CFCs were also used as an electronics solvent, in addition to a refrigerant. There is also R-22 used in most home air conditioners.

Been there, done that

[gerardrj]

If you've had your hands on a peltier, you've probably sandwiched the thing between two heat sinks and two fans. One side is a heater, the other is a cooler. This is the exact method of operation of those in-car cooler/heater boxes you plug in to the cigarette lighter. These kids are simply scaling the idea up; instead of cooling a box in the car they're cooling the car.
There is nothing novel or innovative about this.

Re:Been there, done that

[tomstdenis]

Shhh no they're geniOSes. I mean never in a million years would anyone else figure that out.

I guess what they don't realize is that they take a wack of juice. I have one of those coolers and it draws roughly 60-70 Watts to cool a small area. Imagine an area 10 times larger [hint power requirried doesn't scale linearly].

The real "environmently friendly solution [for homes and offices] is to realize this simple fact. It's cooler underneath the grass and soil.

More trees and grass, cover your campus and your buildings. Let them absorb the sun and voila. Some companies and appartments do this already. But it isn't a wide spread idea unfortunately...

Tom

Re:Been there, done that

[gerardrj]

Another good plan is to cover an above-ground structure's sun exposed surfaces with photovoltaic panels. Arrange the panels such that there is an air gap between the panels and the structure. The panels keep the building from heating up and provide electricity to off-set grid power usage.

Re:Been there, done that

[tomstdenis]

You do realize though that they are not efficient and produce toxic hazards for landfills right?

I'd rather see buildings covered with vegetation that produces oxygene, cools the atmosphere and enables [to use the bizspeak word] nature to co-exist then millions of pounds of uneartly solar cells...

If in the summer [and heck winter] you can cut your climatization power usage that too would offset grid power usage.

Just go research how much an AC compressor takes. They're killowatts for small homes... Think of what an office complex needs... Imagine replacing that with grass, trees, moss, etc. Now imagine doing that to the tens of thousands of office complexes on earth...

Get my point?

Re:Been there, done that

[gerardrj]

PV panels are far more efficient at producing usable energy than plants are. PV panels produce 0.00 grams of "toxic hazards for landfills". All of the materials that make up PV cells are extracted from the Earth. If it comes out of the Earth, putting it back in the Earth later can't possible be a bad thing.

True, plants produce oxygen; they also produce carbon dioxide and water vapor. While the net effect is they take in more CO2 than they exhaust, they also put out more water vapor than they take in. Water vapor is the most effective greenhouse gas. Surely you would want to minimize the output of water vapor if you believe in global warming.

I know how much power A/C units draw. I live in Mesa, AZ where the daily high temperatures over the past two months have averaged about 110F and I have to run both of my 4 ton units to cool the house to livable temperatures. I've looked at the cost and benefits of PV cells. I'd put them up in a heartbeat if they had an ROI of less than 10 years, but the economies of scale haven't kicked in yet. But certainly PV cells would be cheaper than burying my home in soil and irrigating to promote plant growth.

Sure building underground is a great idea. I wish most of the box stores in the Phoenix metro area were underground, it'd mean lower costs for goods since you could use the "roof" for parking and the cooling load would be dramatically reduced. As long as your already digging to put the building underground, using geothermal/groundwater based HVAC units reduces operating costs even further.

Re:Been there, done that

[tomstdenis]

a google search for you

PV cells "come from this earth" but are made of things that when combined then left in a landfill create a problem.

As for the water vapor issue, time will tell on that one. However, I've been to California [re: treelessville] and if you've ever been to Ottawa you can see concreteland (tm) where clear cutting and buildings are the norm.

Yet it's still hot/warm there...

Have you ever walked through a nature trail on a sunny day? Is it totally unplesant and unbearable? I know from where I live outside of the mosquitos and what not it's actually quite ok.

Tom

fRe:e peltier with rebate

[arbitraryaardvark]

Free peltier with rebate.
*informative, stupid*

Re:fRe:e peltier with rebate

[YouCanCallMeAl]

Amusing. I'm from South Dakota and I'm quite familiar with the Leonard Peltier story. I'm a bit surprised to see such a thing posted on Slashdot...

Re:fRe:e peltier with rebate

[bwcarty]

Rage Against the Machine made the Leonard Peltier story a bit more famous.

Re:fRe:e peltier with rebate

[Southpaw018]

Anyone that was involved with the American Indian Movement on both sides - the FBI agents and the protestors - should be in jail, Peltier included.

Amazing how his site (and not so amazing how his legal briefs) fail to mention that the "unlawful military response" was sparked by the shooting of several FBI agents - or that it was the protestors, not the government or any of its agents, who shot first.

Re:Peltiers

[failure-man]

In this case 400% efficiency is referring to heat moved over work done. I'm not sure if a car system is actually that good, but moving more heat than you put in is typical behavior for a modern refrigeration system.

Re:Peltiers

[Anonymous Coward]

Different news paper same type of content.
Deseret News Article

Re:Peltiers

[turbod]

I would agree that it is good that kids experiment, however, adults shouldn't stand by while children mislead themselves. Some adult should have taught them how to calculate COP and pump efficiency rather than letting a article make it to the national level which may end up embarrasing those children.

That's the danger of the current crop of teachers in many schools who don't really know the subject they are teaching.

Re:Peltiers

[InvalidError]

Cooling efficiency is expressed with the "Coefficient of Performance" (COP), and is the ratio of displaced energy and input energy.

If you need 1kW (or 1kJ/s) to displace 10kW (10kJ/s), the COP is 10. This means the displaced energy is ten times as much as the energy used to move it.

Now, the catch with Peltier elements is that they have high COP only at very low power and small temperature difference, usually around 5-10% of the power rating and 10C temperature difference. Unless they are operated under these optimal constraints, their COP quickly drops under five. So, to produce a highly efficient TEC AC able to handle 1000W, one would need a 1kW TEC bank operated at ~80W. Considering that a TEC costs about $0.25 per rated watt, this efficient solution would cost over $250, roughly twice the price of an average room AC... and it gets worse: 1kW is barely enough to cool one square meter worth of solar heating, car and house windows have a much larger surface area total than that.

Note: a TEC's 100% rating is where the TEC barely manages to pump its own heat away from the cold side. TECs used for thermal regulation usually operate in the 30-50% range. The high-efficiency range is usually somewhere around 5% with COPs sometimes reaching over 15. For comparison, the theoretical limit for freon (and many substitutes) is around 16 but the best practical implementations only reach around 12.

Now, a typical room AC pumps from 5kW to 12kW with a temperature delta around 20C with a COP around 10. So, to beat the phase-change system's efficiency, the TEC solution would have to be beefed up by about 20X (10X the load, 2X the delta), bringing the cost around $5k, which is 20X as expensive as good classic AC.

Until they find materials that offer both better electrical conductivity and better thermal insulation to improve their overall performance (widen their sweet spot and move it up the power curve), TECs will remain a somewhat marginal cooling solution.

Re:Peltiers

[ErichTheWebGuy]

You are quite wrong. Just FYI, I am EPA certified for handling of refrigerants, as well as installation, service, and disposal of cooling systems, in all automotive, commercial, and residential applications.

ANYWAY, the statement you made is blatantly wrong. Seldom are those components disposed of. In salvage yards, those are often the first components that are recycled from a vehicle for further aftermarket use. And you cannot get them unless the system has been discharged according to EPA regs. This involves recovery equipment, as well as a huge mount of training and certification of personnel. That means big money generated from those components. Do you really think that salvage yards would just crush and bury such a money-maker? The same thing applies to automotive service shops. The system cannot be disassembled without having been previously discharged according to to the regs. Even then, the shop usually makes a few bucks recycling the faulty components that have been removed.

So, your statement that automotive A/C components from a traditional system contribute to overall pollution is mostly bull. NEXT!

Yeah, right.

[AaronLawrence]

Seems to me like they have
a) bought a few cheap peltier chips
b) use fans to get a slightly cool breeze out of them
c) Assumed that this is the same as a car A/C unit

In fact car A/Cs have quite a large amount of cooling power, probably 100 times what they are producing.

As anyone with half a clue about this knows, Peltier devices are very INefficient, and are only useful in certain circumstances where the inefficiency doesn't matter (such as a really hot server chip where you don't care how much energy you waste, to get the heat out of it).

It's not like they've invented a new type of Peltier device; they openly say they bought some chips of Ebay.

It would be nice if they had discovered some new effect or configuration, but to me it sounds more like cluelessness and a bunch of equally clueless adults encouraging them. In reality cooling technology is very well understood.

Freon Scam

[argoff]

Ahem. "Today's" cars use R134a refrigerant, not ozone-depleting freon. This has been the standard for a little less than ten years now.

In all fairness r234a is probably more harmfull than freon because of it's chemichal structure, and freon is really not nearly as harmfull to the environment as people say it is. see here

Also, something should be explained to the naieve masses: Freon became illegal THE VERY MONTH that DOW Chemichal's patent expired! But did DOW suffer, NO! They still hold patnets on the few similar replacements These patnets would have been worthless had freon not been made illegal. But it is illegal, so they are very valuable. Are the replacemnets safer, NO, are they cheaper NO, are they more environmentally friendly NO. Do they work better in machinery NO. The only reason why we are using them today is because they are patented, and DOW wanted to preserve their revenue stream. That is all. It is not for the environment, it is not for the ozone, and never was - that was just a poor excuse to push freon out of the marketplace.

People would wise to learn that usually when a company talks about preserving the environment, what they mean in business talk is "increase the regulatory barriers to entry for potential competitors in their industry, and push up revenue by driving used products out of the market place"

Heat dissipation in BTU? Ambient performance?

[fishbowl]

Tomorrow will be the 35th consecutive day of temperatures over 100F in Tucson. That's not as bad as it probably sounds in Maryland or Georgia. Yes, it's very damned hot (as high as 118F!), but evap coolers actually work... and you sort of have to want to live around here. Still I'll take 110 in Arizona over 89 in DC or Atlanta (all of which I've experienced recently.)

Anyway, I want to know how the Peltier cooler works in all different conditions of temperature, humidity, barometric pressure, and altitude.

Re:Great! Here's why it won't happen...

[Forbman]

You think so? The little peltier-cooled (or heated) coolers have not put Coleman, Igloo, et al. out of business, especially since they make their own.

So, if it can scale well enough, and Delphi, et al can source enough of them from China, and the HP loss from the increased alternator load is less than the HP loss from running the AC compressor for about the same BTU output, then it'll fly.

Besides, I'd much rather deal with replacing an alternator than an AC compressor, and in 5-10 years, some really BIG, high capacity peltier chips will start being available at junk yards...

Re:The problem is the power supply from the Altena

[Khyber]

Most cars can't spare 150 watts??

Boy, I better take this 200 watt amplifier out of my car, then.

Re:The problem is the power supply from the Altena

[ColaMan]

than why do all modern cars disengage the A/C clutch when you go wide open throttle?

To state the bleedin' obvious:
For the maximum kick-in-the-pants that everyone likes to see from their car - especially manufacturers trying to woo car reviewers. A few seconds with the compressor off while you accelerate to 60 makes no real difference.

There are also technical limits:
- Assuming that the compressor is overdriven from the crankshaft pulley about 1.5 to 1 (about normal), a car with a redline of 6Krpm is going to tear up its compressor (9Krpm) quick smart.
- Required drive power increases as well - a compressor using 1.5kw at idle speeds could use an extra (possibly belt-snapping) 3 or 4kW at full noise.

But it's mainly for driveability.

cooleraters are insulated

[YesIAmAScript]

And it's cooling a much SMALLER space. The cube fridge cools over 1 cubic foot of space. The Coolerator is cooling an area the volume of just over two six-packs.

And Coolerators are insulated, they are built in the chassis of a regular cooler. Coolers are obviously insulated, it's the reason people buy them instead of using a plastic storage box. Who would build a cooler that wasn't insulated? That'd just be insane. Even if you did it and made it work, your competitor would make an insulated version, ditch 3/4 of the expensive eletronic cooler doodads and kick your ass in the marketplace by undercutting your price by 50% and still selling at higher margins.

Read the other threads, not just this one. Peltiers are very poor. They just don't move enough energy for any given power consumption. In fact, since the energy you put in also turns to heat and you put it in right next to the "cold side", it often ends up heating up the thing you wanted to cool instead of cooling it down.

Coworker has a device like at the link. The only good thing about it is it is quiet.

http://www.target.com/gp/detail.html/602-0442749-7 071848?asin=B00008O384&AFID=k40132&AFID=SMX&ref=tg t_adv_XSD10000

Look at the size of it. Does that look as large as a cube fridge to you? Other links will tell you it has about a 6-liter capacity. One cubic foot is 28 liters. And cube fridges are over 1 cubic foot. Again, see link. 1.7 cu. ft. That's 48 liters. 8 times the size of the thermoelectric fridge.

http://www.target.com/gp/detail.html/sr=2-3/qid=11 21924434/ref=sr_2_3/602-0442749-7071848?_encoding= UTF8&asin=B0009EXXWO

I did make a slight error, the first units were called Koolatrons, not coolerators. But both words are used now.

Acoustic refrigeration?

[RubberDogBone]

I'd like to see more practical applications of acoustic refrigeration.

Apparently Ben and Jerry's is installing them in stores. Forget that. I want to be able to buy one at Home Depot so I don't have to keep buying crappy standard window air conditioners with their loud compressors.

Re:Acoustic refrigeration?

[RubberDogBone]

Sounds like a new idea for a razor product.

There's money to be made in hair removal AND in hair replacement.

1) Invent gadget for hair removal, open chain of shops.
2) Profit!
3) Open hair replacement chain.
4) Profit!
5) Goto 1

Re:The problem is the power supply from the Altena

[Khyber]

150 watts is not that much.

Your typical alternators does 80-100A, yes, but it's not doing purely 12 volts. First, it's AC, cars use DC. There's a rectifier built onto the alternator. Secondly, depending upon the rotation speed of the alternator, you're going to produce anywhere from 9 volt - 18 volts. (For those of you who've had the oldskool battery gauge in your dash, you knwo what I'm talkign about. You rev that engine up, that needle jumps up.)

If 150 watts was really too much to ask for, you think people would be able to throw 1600 watt amps into their stock car and drive away happy? I wouldn't either, but they can, and they do, all the time. No new alternator, no extra battery, nor no extra alternator. Everyday they do this across the street from my house at the old Stereo One.

HP at low revs...

[YesIAmAScript]

Essentially all cars make less power at lower revs than at higher revs. Why? Because HP is torque (in ft/lbs.) * RPMs / 5252. If you cut the revs in half you cut the HP in half unless you double the torque. And you didn't.

But I'll say this, if that car makes 100HP at 2500 RPMs, it makes more than 50HP at 2000RPMs.

But anyway, who cares? The post you responded to said "a couple KW". Let's say 3KW. That's 4HP. Even if you car is only making 50HP, losing 4HP isn't going to put you out too badly.

Note that it takes a pitifully small amount of power to accelerate a car under normal conditions. A regular-speed acceleration can be executed with under 50HP, of course depending on the weight of the car.

Re:HP at low revs...

[photon317]

Note that it takes a pitifully small amount of power to accelerate a car under normal conditions. A regular-speed acceleration can be executed with under 50HP, of course depending on the weight of the car.

I see you've become so used to your hybrid Prius that you've lost all perspective on what acceleration is :)

Re:HP at low revs...

[evilpenguin]

DC electric motors can be built to have far more torque than any internal combustion engine. It's one of two reasons that railroad locomotives are motor generators (the huge diesel engines generate electricity and electric motors turn the wheels).

The other major reason, of course, is that by using electricity it is fairly easy to hook multitple locomotives together to haul a load. Imagine having to hook up multitple locomotives through a mechanical drive train and then keep all the engines in perfect sync, with perfectly even throttle/rpms? I can't imagine such a system. Well, I can. But I wouldn't want to have to build it, maintain it, or use it!

The torque of a DC motor is limited only by the number turns of wire you've got and the strength of the driveshaft (and, of course, on the amount of electricity available!)

Of course, now I have to admit that I don't know any details about the specs of the Prius' motors, but I haven't heard that they have poor acceleration. They also have CVTs, so they might very well seem to accelerate better simply because it is continuously smooth...

Re:Peltiers

[ErichTheWebGuy]

You clearly have zero experience in the HVAC/R industry. A system that is leaky will typically freeze up at the evaporator coil (if you require more explanation as to the operation of an air conditioning/refrigeration system, please let me know), thereby rendering the system useless and requiring service.

A leak is typically small enough that it does *not* leak all of the refrigerant into the atmosphere. Indeed, the typical leak vents less than 20% of its capacity to atmosphere before the owner notes a malfunction that causes the system to cease function. This phenomena is common to any modern cooling system, which includes your freezer, A/C, fridge, water cooler, beer cooler, car A/C, etc.

As far as refrigerant being released intentionally, the cost of recovery equipment and personnel training is nill compared to the cost of fines, paperwork, re-certification, additional inspections, etc associated with guys who vent to atmosphere. Think it never happens? I worked for a company who had a guy that released refrigerant to atmosphere. Consumers are surprisingly informed about refrigerants and ozone/greenhouse damage. I can tell you that it cost no less than $100,000 for the company to get back in good standing, and the tech got his certs pulled and will never work in the industry again.

So... NEXT!

Re:Peltiers

[Stauf]

Take a look at this Wikipedia Talk. Basically, as a device to heat a space, a heat pump is greater then 100% efficient because the energy you input into the system is smaller then the amount of heat energy you 'add' to the room. I couldn't find any properly detailed sources on the issue with a quick google search.

I had it explained to me something like this: If you imagine a device intended to push a huge boulder off a cliff, that device only needs to be provided with enough power to nudge the rock. However, if you measure the device's efficiency in terms of energy required to move the boulder all the way to the ground divided by the energy usage of the device - you get a device with greater then 100% efficiency.

Young men, tinkering in garages, changed the world

[gbulmash]

I keep seeing posts about how the whole idea is ludicrous and has been proven ludicrous.

How many of you have an income because of young guys, tinkering in garages, defying conventional wisdom, doing things experts condemned as impossible or improbable, or in some cases just finding a way to do some existing thing in a much better way?

I know this looks like BS on the surface, but just possibly they had an epiphany no one else has had and figured out a better way. From this tiny article, you got the schematics and engineering specifications of their devide? You know it can't work?

Unlikely that it's a true innovation? Possibly. No way in hell it's a true innovation? You're brave men to deal in such absolutes.

- G

troll

[shiftless]

I'm sorry, but you're completely full of shit. Every time my A/C compressor clicks on while I'm driving, I can tell; I drive a manual, and if I'm paying enough attention, I can tell especially if revs are low (ie 2k).

Of course you can tell when it clicks on. However, in 99% of the cars out there, the A/C does not effect driveability a noticeable amount.

This was the grandparent's point. So the air conditioner takes up, say, 5% of your engine power while you're cruising at a low RPMs. Big deal. Maybe the car feels a tad sluggish when accelerating at part throttle. That's OK, because when you floor it, the air conditioner clutch disengages and you have full engine power at your command.

I drive a Mustang with that engine, and while I can tell when the A/C clicks on, driveability is in no way impaired. If a person is worried about having a slow, underpowered car, why doesn't he get a car with a V8 or turbocharger?

Re:troll

[Desert Raven]

If a person is worried about having a slow, underpowered car, why doesn't he get a car with a V8 or turbocharger?

Hey, slow isn't always underpowered. :)

I drive a truck that I frequently pull a 10,000lb trailer with. With or without the trailer, I really can't tell when the A/C kicks in. I'm not going to break any speed records with this rig, but I'm developing most of my power in the lower rpm range.

Re:troll

[Surt]

That can't be true. I've driven about 20 different models of cars, a couple of light trucks, a couple of SUVs. Manuals and automatics. It was blatantly obvious when the A/C was on vs off in every one of them.

To most people I know, it is again blatantly obvious how a car 'struggles' with the a/c on vs off. I'm pretty sure we're not some odd minority either, because most of us aren't particularly interested in cars or anything.

Re:troll

[CharlieHedlin]

My MX-5 would certainly cut off the AC at full throttle. If I ran at full throttle for any length of time on a hot Texas day I could feel the cabin temp rise.

The AC didn't affect the drivability at all. It affected gas milage a little. If the AC was on, I had to use more gas, but the top end wasn't affected because the car would turn off the AC.

Re:troll

[shiftless]

Baloney. A Corvette with the LS1/LS6 motor runs 12s in the 1/4 mile and gets 30 MPG on the interstate. A Ford 2.3 turbo car can be cheaply modified to run just as fast and get 35 MPG on the interstate. Just because it's a V8 or fast doesn't mean it has to drink gas. With today's technology (and in the case of the 2.3T, 80's technology), we can make cars that have good acceleration while retaining excellent fuel mileage.

Re:troll

[shiftless]

Exactly. The vast majority of production gas engines, and all diesel engines, are designed to make a lot of torque at lower RPMs. Diesels are inherently that way, and gas engines are designed that way to enhance driveability. If someone's air conditioning slows the car down too much, they need a bigger engine, period.

incorrect

[zippthorne]

Plants do emit CO2, they emit it during aerobic respiration just like the rest of us. It's just that they also have a phase where they basically run that whole thing in reverse.

Hurry up with that patent!

[Duncan3]

Seriously.

As an invention made of real atoms, you won't see one in real life until the patent EXPIRES. Then everyone will have one. Cars are designed half a decade before you see them.

Sorry, but that's how things work in the real world. It's nothing like the world of bits we all live in.

So, anyone out there know anyone that can accelerate this one?

Yes Moving Parts

[Kadin2048]

You are correct, but the comparison between the Peltier chips and the entire A/C system in today's car is not apt.

You might as well point out that the evaporator coils of a standard air conditioner have no moving parts. They don't -- however other parts of the system which are necessary for them to do anything worthwhile do.

Likewise, in a peltier-cooler based A/C system, the cooling junctions themselves have no moving parts, but you need (at the very least) a fan to move the air over them, plus you need a source of electricity: probably the car's alternator. As others have pointed out, this will put just as much load on the engine's fan belt as a regular mechanical compressor would, and quite possibly much more because peltier junctions are so inefficient when compared with traditional refrigeration systems.

The entire system as a whole (unless you have an electric vehicle) would not be completely devoid of mechanical parts, and never can be, since the power source is an internal combustion engine and it's output is not naturally electric.

Since the late 90s, eh?

[Descalzo]

That's why I drive OLD CARS!!! THE A/C rocks. Vivan los viejos!

There is another major one.

[WindBourne]

How often does somebody run the AC?
For the USA, More than 1/2 will run it for less than 3 months a year. So for 3/4 to 5/6 of a year, it is dead weight, that is simply waiting to fall apart.

OTH, with your idea, the peltiers can be ran in reverse and heat the car, as well as cool.

Re:There is another major one.

[Desert Raven]

OTH, with your idea, the peltiers can be ran in reverse and heat the car, as well as cool.

Which would have to be the dumbest idea I've heard of for any vehicle with an I/C engine. Even the smallest internal combustion engine gives off a huge amount of waste heat. This gives you all the heat you want, at no additional cost.

For an electric or hybrid running on electric, it makes just enough sense to get you to the realization that you really can't afford to drain your batteries just for cabin heat. The smarter move here is to put on another sweater.

Re:There is another major one.

[WindBourne]

The parent to me posted about including Solar on the car to help cool it during the summer WHILE it is sitting there. I mentioned that using the solar to heat the car during winter WHILE it is sitting there. IOW, there is no engine heat happening during that time. It is a nice way to heat the car a few degrees when the outside temp is 0, or to cool the car during the summer.

Re:Peltiers

[E Galois]

Yep, it's generally referred to as the latent heat of fusion, although in a refrigeration context it might be more appropriate to discuss the latent heat of vaporization/condensation - the heat required for phase change from liquid to gas or gas to liquid (about 540 cal/g for water).

Also, although quantitatively correct, the choice of units in your illustration strikes me as a bit odd. Without getting into all the baroque details, in the metric system a calorie is generally defined as the amount of heat required to raise the temperature of one gram of water by one degree Celsius. This would seem to make the Celsius scale more natural when talking about calories (and would make your example run from 0 degrees C to 80 degrees C).

Analogously in the English system, a British thermal unit (Btu) is generally defined as the amount of heat required to raise the temperature of one Lb. of water by one degree Fahrenheit.

More efficient?

[Svartalf]

I thought that Peltiers, except for the thin-film variety, had a COP that was less than 1. Simply put the things take about 1.5-2 times the juice they're pumping. This is due to Joule Heating losses, etc. in the bulk semiconductor materials they're using.

Alternator, Shmalternator

[EvilMidnightBomber]

The problem is the power supply from the Altenator

Then run it from a thermoelectric generator attached to the exhaust manifold/catalytic converters. Engines are spectacularly efficient at producing heat and since the thermoelectric generator is just a peltier device working backwards the current/voltage characteristic is a perfect match. Peltiers, Thermoelectrics, and the Seeback effect

Re:Alternator, Shmalternator

[ab762]

run it from a thermoelectric generator... peltier device working backwards the current/voltage characteristic is a perfect match...

You do realize that you've just described something rather like a perpertual motion machine? It's not quite, but to use a hot-to-warm difference to create an equal warm-to-cold difference is pushing it a bit.

It just might work with the "cold" - really warm - end of the generator cooled by airflow through a honkin' set of cooling fins, while the car's moving. There would be some wide-reaching redesigns - generally the electronics keeps well away from the hot parts of the exhaust. But the catalytic convertor is notoriously hot.

I easily found a commercial 19 W module that runs between a 450F/230C hot side and an 85F/30C cold side. The graphs on the spec sheet show lower efficiency with a cold side as warm as 100C. 3 inches square. And they take PayPal!!! $154 US. I'm actually tempted to buy one and mount it on my muffler just for geek value.

I'd expect you'd be lucky to get 50% total efficiency. That may be in the commercial domain, ask an economist.

Re:Alternator, Shmalternator

[zerus]

I think he means something like the Seebeck effect which is the reverse of the Peltier effect, meaning you get energy and electrons are pushed through the npn junction when going from the hot side to the cold side. Obviously you'd lose efficiency when it's a hot to warm conversion because of the lower gradient. It's not a perpetual motion machine, it's been around for almost 200 years and is probably most famously used on modern satellites and probes in the form of RTG's (radioisotope thermal generators).

Did you hear the noise they make though?

[brunos]

Pulse tubes make a really annoying high-pitch noise, and they need quite a large compressor too... They also cost 50000$. (Have 2) I have never been quite sure why the Stirling stuff is not used more, maybe there are implementation problems ...

Re:Did you hear the noise they make though?

[budgenator]

implimentation is a tad bit touchey, and just about everything patentable about them has been done and expired, they are used in cyrogenics, the stirling has no rotating parts, is driven ala solenoid and can be hermeticaly sealed to reduce maintenance and failures. I have no idea about real world efficencies.

Coolchips

[DiniZuli]

I gues they used regular peltier chips, invented a long time ago.
But I can't wait to these get to market.
They have build a prototype fab somewhere in eastern europe, are a little late on schedule because of lack of funding, but it still sounds prommising to me. They have been mentioned on Slashdot before.

Re:No more freon in cars...With those last 3 words

[davidsyes]

I'll bet you make Frigidaire STOCK (stalk) rise on a hot day in Tejas...

----

wow, an anti-script image that actually spells a word.. "BLADES"

Save Utah's ozone. Pollute China.

[heroine]

There's a reason they don't make semiconductors in US. Making semiconductors consumes enourmous amounts of resources and requires nasty chemicals like arsenic. So instead of releasing freon into US's atmosphere you release arsenic into China's water, make China burn vast amounts of fuel to bake silicon, and make China kill vast numbers of Panda bears to mine materials.

Re:scientific method?

[SmittyTheBold]

No, it's not, because retards like the grandparent get the impression that something has been proven scientifically when it really hasn't.

King Bedevere does a better job of establishing a woman's witch-hood than those guys do "explaining" everyday occurrences.

[Addendum]

[SmittyTheBold]

Remember when the Discovery Channel was all about actual learning and knowledge?

On a related note, remember when MTV involved music?

And the Republican party was conservative?

Re:[Addendum]

[Presidential]

Remember when the Discovery Channel was all about actual learning and knowledge?

On a related note, remember when MTV involved music?

And the Republican party was conservative?

Pepperidge Farm remembers!

Re:[Addendum]

[ThJ]

I miss those days. Discovery channel still has educational shows (I think...) but they stuff them away, never in prime time.

Re:[Addendum]

[buraianto]

comment++

Re:[Addendum]

[Kehvarl]

Are you still preoccupied with 1985?

Re:[Addendum]

[SmittyTheBold]

Well, it was a good year, I suppose. But I'm really just trying to get a head start on being a cranky old bastard.

Worse than that...

[Atario]

When you breathe, you deplete the atmosphere of life-giving oxygen molecules and inject the well-known greenhouse gas, carbon dioxide.

Death is the only true environmentalist.

Re:Worse than that...

[msaulters]

When things die, they decompose, releasing a plethora of various greenhouse gases. So while the O2 consumption is stopped, pollution is still increased.

Death is a Republican.

Lets have it!

[connor_macleod]

how do we get these things to market faster? water powered cars have been around for like 15 years or something!

http://www.spiritofmaat.com/archive/watercar/h20ca r2.htm

does anyone have a list of all the sustainable-environment inventions that have not made it to market? It would be great to see the internet promote knowledge of them to a point where governments must help them get made and enforce their use.

Re:Peltiers

[Abm0raz]

I'm sure you meant C(oeffecient) O(f) P(erformance) and NOT efficency.

COP is defined as HEAT_RATE_REMOVED_FROM_COLD_RESEVIOR/WORK_RATE_REQ UIRED_TO_RUN_THE_PUMP
(also written as Q(dot)[L)/W(dot)[pump]). A simple thermodynamics course in Mechanical Engineering will tell you that THE maximum efficiency an refrigderator (reverse heat-pump, such as an air conditioner) can reach is T(L)/(T(H)-T(L)) where T(L) is the absolute* scale temperature of the low heat resevoir and T(H) is the absolute scale temperature level of the high heat resevoir. This value can exceed unity (1) and generally ranges from 2-5.

Efficiency of the heat pump or refridgerator is defined as USEFUL_WORK_PRODUCED/ENERGY_REQUIRED. For a refridgerator, this is written as Q(L)/W(in). Since Q(L) for a no-loss system is defined as Q(L)==Q(H)-W(in)** Through some equation manipulations shown on page 7-24 of the referenced book(see end of post) it's shown that Q(L)/Q(H) = T(L)/T(H) and that the efficency is defined as 1-T(L)/T(H) and that this value is always less than one as by definition of T(H) > T(L).

Appendices:
Source: Thermal-Fluid Sciences: An Integrated Approach 3rd ed, Dr. Stephen R. Turns Ph.D., 2003, Published by the Pennsylvania State Universit Department of Mechanical & Nuclear Engineering.

A heat pump/refridgerator is defined as a high temp resevior and a low temp resevior sufficently large that any instantanious heat added or subtracted by the system will not significantly affect their temperature. Between these reseviors is a pump that moves heat from the low temp to the high temp by performing work on the system. It receives the energy to perform the work from outside the system. The second law of thermodynamics*** says that because the natural entropy of the system would be an equalized temperature between the reseviors, the energy required to move heat the other direction must be greater than the actual energy moved (thus the efficency can never be greater than 1).

Q(dot)[L] => Rate heat is removed from low temp resevior
Q(dot)[H} => Rate heat is added to high temp resevior
W(dot)[pump] => Rate work is used by the pump
Q(L} => Heat removed low temp resevior
Q(H) => Heat added to high temp resevior
T(L) => Absolute temperature of the low temp resevior
T(H) => Absolute temperature of the high temp resevior
W(in) => Work required by the pump

* Absolute scale can be either Kelvin, Rankine, or any other linear proprietary temperature scale where there is no negative temp and that sets its lowest temperature at the temperature at which all molecular movbement stops (absolute zero)

** There is no such thing as a no-loss engine in real life. There will always be friction, drag, and/or head loss (for turbine/pump/fan driven air conditioners) or electrical resistance (for things such as peltier coolers). So the real equations is: Q(L)==Q(H)-W(in)-W(loss) where W(loss) is the total work lost overcoming internal forces such as drag, resitances, etc..) That W(loss) makes the maximum heat removed from the low temp resevior even less, thereby reducing the efficiency.

*** Among other things, it says: "Work can be converted entirely into heat. Heat cannot be converted entirely into work."

-Ab

ps. "Lisa, in this house, we obey the laws of thermodynamics!" -Homer Simpson

Re:Great! Here's why it won't happen...

[pe1chl]

It won't happen because it will put the current freon industry out of business.

You are not going to tell us that the use of freon is still allowed in the USA, aren't you??

Or... just move further north

[evilandi]

I just don't get why people need air conditioners. And I especially don't get why people think that they can be environmentally friendly by redesigning one. The environmentally friendly solution is not to need one.

Just move further towards the pole.

Here in England we just don't need them. It never gets that hot. We don't get significant droughts or forest fires or earthquakes or whatever. The few heat and water problems we have are entirely down to overcrowding in London; again, my solution is: don't live there.

I just don't understand what was in the mind of some colonist when he went to, say, Utah and thought to himself "Yeah, this is a good place to live" when it quite blatantly the weather is going to try to kill you for four months of the year. I visited Texas in summer once; everyone spent the whole time moving between air conditioned houses to air conditioned cars to air conditions offices and air conditioned shops. They might as well have lived underground.

How on earth did we end up living in such daft places?

Re:Or... just move further north

[Yaotzin]

In the winter, we often use it to heat up the cars.

Re:Or... just move further north

[aXis100]

I am intrigued by your ideas and would like to subsribe to your magazine.

Re:Or... just move further north

[bhima]

I've heard it all now, someone from England talking about the good weather there! The reason it is not that hot in England is that the sun's rays rarely penetrate the incessant cloud cover. It's hard to have a heat wave in the middle of horizontal rain! Sure it get warm in Texas... but it's a dry heat! ;)

Next he's going start up on the good "Food" they have in England. Don't you realize that the reason that England had so many colonies was because they were trying to escape the weather and the food!

I guess I should admit now that I don't need AC where I live either and I will never, ever go to Texas in the summer.

Re:Or... just move further north

[Zarf]

How on earth did we end up living in such daft places?

geo-chauvinist

Re:The problem is the power supply from the Altena

[JaredOfEuropa]

Well, if they have developed a peltier system that rivals an electric-powered vapor-phase system in efficency, their technology could very well find its way into future hybrid vehicles.

They've simply used regular Peltier elements hooked up to a second alternator in a car. Given the efficiency of these Peltier elements compared to a compressor-driven alternator, I'd say this system will require more power from the engine to put out the same nr. of BTU's as a regular car airco. As someone else said; this airco doesn't use less power than regular units because it is more efficient, it uses less because it cools a lot less.

Another thing is that (for me) the most important thing about airco is not that it cools the air, but that it removes moisture from it. Will this Peltier airco do that as well?

Memory loss?

[Trinition]

Can't remember any of us dying from it. Heck, I can't remember anyone getting *sick* from it

So maybe in smaller sustained doses, Amonia just causes memory loss instead of death? Better, but still bad :)

I spend a lot of time in Africa

[The Mutant]

on biz, and you really need Air Conditioners there. I don't think the folks living there really had much of a choice but, then again, I've never asked them. And where would they go?

Freon is illegal

[Blitzenn]

The article, as posted on Slashdot, is not correct. It is illegal under federal law to produce any new equipment using Freon and illegal to manufacture it in the States. See this article or search google for yourself. Granted there is a lot of hoopla about it's replacements not being so good either, but the Freon arguement is dead. You can still buy Freon, but only freon that has been recovered from existing systems.

Re:Young men, tinkering in garages, changed the wo

[patrikr]

You're brave men to deal in such absolutes.

Only the Sith deal in absolutes! ;-)

Re:Damn yank cars!

[one_who_uses_unix]

I would be glad to get rid of my Chevy Suburban - just as soon as someone can provide a vehicle capable of carrying the 6 children and 2 adults that I need to carry and that can navigate the 2 miles of gravel from my house to the hardtop after a good rain or snow!

Many, Many, Many things wrong with the article!

[Ancient_Hacker]

Let's count the things tha are completely and verifiably wrong in the article:

• Peltiers are efficient-- NOT! They have an EER of way less than 1.0. A window air conditioner is above 10. End of discussion.
• There's no way to make them more efficient-- think-- they have their cold side right next to their hot side-- there's a lot of thermal conductivity there, effectively undoing a big percentage of the cooling.
• It's NOT more efficient to draw electrical power than to draw engine power. Somehow the kids think the alternator turns for free. Nope, it draws engine power just like the old AC, and as all defvices are less than 100% efficient, it has to be LESS efficient to use the power downstream from the alternator. { Minor caveat-- the alternator has the advantage of being able to put out more constant power-- direct drive from the engine to the compressor results in less AC (but not necessarily lower efficiency AC) available at slow engine speeds.)
• A typical auto AC puts out 30,000 to 50,000 BTUS/hr of cooling. A 1x1 inch peltier chip does about 150 BTU/hr at a cost of $9.95 on the surplus market. To duplicate a regular car AC would require 200 to 350 chips, $2000 to $3500. Plus a bunch more alternators, they'd need 1400 amps, about 20 alternators. Hard to fit them all under the hood.
• Peltiers do not last forever. They're prone to breakage due to cyclic stresses and degradation from humidity.

A REALLY bad aricle. The laws of thermodynamics rule.

Econo Cars

[mdarksbane]

I'd sure *love* to have a car with a V8 (you know, aside from the horribly wasteful gas mileage on them these days), but in the cheap 10-year-old econocar I can actually afford, turning on the AC makes a HUGE difference.

It never feels underpowered under normal circumstances (not overpowered either, but very tolerable acceleration), but it's gotten to the point where I switch off the AC any time I'm merging onto the freeway. Cuts my acceleration almost as much as moving my entire dorm room in the backseat did.

I'd definitely be happy if they made the AC a little less noticeable in a small car ;-)

Re:Econo Cars

[jpostel]

I'll agree with you on the V8. Until I got my current car, I could really tell the difference when the AC was on. Now that I drive a tank with a hood ornament (91 MB 560SEL), I can barely tell the difference. I only notice it when I really floor it at already good speeds, like going around a 18-wheeler at 75-80 mph.

My old car was a 94 Subaru Justy. Those that have driven them, love them. You could feel the sluggishness if you had the AC on, or if you put two passengers in it for that matter.

Re:Damn yank cars!

[Zemplar]

"I would be glad to get rid of my Chevy Suburban - just as soon as someone can provide a vehicle capable of carrying the 6 children and 2 adults that I need to carry and that can navigate the 2 miles of gravel from my house to the hardtop after a good rain or snow!"

Have a look at the Toyota Sequoia. Great vehicle, and the A/C works superb!

Re:Damn yank cars!

[one_who_uses_unix]

Thanks for the link - the Sequoia looks great, but unfortunately the 4WD MPG is 15/18 - no different than what I get in my suburban - I routinely get 17MPG.

Clueless kids

[wowbagger]

These kids ignore the facts that:

1. Peltiers are MUCH less efficient at moving heat than mechanical phase change coolers.
2. The electrical energy to drive the Peltiers will come from somewhere, namely the alternator.
3. The increased load on the alternator will in turn cause the alternator to place an increased load on the engine, reducing gas milage.

These kids didn't really test their system - as in, make measurements of fuel economy with the old system and with the new system in real conditions and see what the difference was. They just assumed that "If we get rid of the load from the compressor, we will save 10 HP that will save X amount of fuel" (ignoring the load from the alternator).

Now, if they had wanted to REALLY do something that would cool the vehicle without costing more gas, they would have mated an adsorption cooler to the exhaust manifold, and recovered the energy to run the cooling system from the waste heat discarded to the atmosphere.

A few points

[Muad'Dave]

• As has been mentioned, this isn't exactly a new invention or particularly innovative. As we've all seen from the patent office's behavior, something can be seen as innovative and blindingly obvious at the same time.
• Many posters have commented on the amount of power needed to run Peltier's - remember that in the not-too-distant future cars will have 48-52V electrical systems with alternators capable of much higher power output. Car's electrical systems are already taxed given the recent proliferation of nav systems, DVD players, laptop power outlets, etc., so the move to more powerful electrical systems is underway.

  Here are a few of the things that become possible with that kind of available power:

  1. Engines with electrically-actuated valve trains - no more camshaft, timing belt, rocker arms, pushrods, etc.
  2. Electrically powered power steering (as is done on my Mini Cooper S), eliminating that belt.
  3. Electrically powered A/C system
  4. The alternator either integrated in the block, or bolted directly to the crank. Imagine that - an engine with no belts!

• Wouldn't it be interesting to develop a cooling element that combined the Peltier effect and the Piezoelectric effect? Anchor one end and let the other flap, apply pulsed DC to it and you get cooling and a fan!

Re:A few points

[derubergeek]

The alternator either integrated in the block, or bolted directly to the crank. Imagine that - an engine with no belts!

So long has you remember to add the electric coolant recirculating pump to the list. Although, as far as the alternator goes, one could always make the flywheel do double duty in that regard.

Re:A few points

[Muad'Dave]

Ah - an excellent point. It'd make sense to use an electric pump since you could then optimize the block temp by varying the pump speed. No need for a thermostat.

Re:A few points

[Merovign]

I really have to get into auto repair.

"Oooh, you got one o' dem new-fangled inetegrated electronic engines. That mysterious low voltage will be $200 to diagnose, and if it's the integrated alternator, we'll have to have the engine apart... and that'll be $1000 to remove and replace the engine, $400 labor on the engine, $250 in seals and bearings, and $280 for the alternator."

I think I'm going to start buying really old cars, actually. ....bolted directly to the crank... I hope you meant a gear interface with the crank, otherwise just assume a $5000 engine replacement if the alternator fails.

Technology integration only makes sense if it makes the "package" cheap enough to replace that you can "recycle" or throw away the old one if one part fails.

Re:A few points

[Muad'Dave]

You're correct - I didn't mean 'integrated' like 'irreplacable' or 'not removable'. I meant part of the overall design, not stuck on like an aftertought and driven by a belt.

I'd like to see something more elegant, like the alternator and water pump connected internally, much like current distributor shafts are driven from a dedicated gear off the camshaft. It would be nice to develop a standard mounting face and shaft like those on electric motors, but I doubt manufacturers would go for it.

Re:The problem is the power supply from the Altena

[SirCyn]

The 200 watt amp CAN suck down that much power. It does not normally. And if it does, it's only for a few seconds, and the battery provides the power.

R-12 Conspiracy

[jeepliberty]

If you are into conspiracy theories - here's one. DuPont's patent was about to expire on Freon R12. So they conspired to have it banned for environmental reasons.

But not before they invented a new ozone friendly refrigerant (R-134a) with a new patent life. I hear that there are properties of 134 that are just as eco-unfriendly as the original.

As far as solid state refrigeration, it's been around for years. You can google it and find small solid-state dorm refrigerators and similar ice boxes for boating industry. I'm not sure if it would scale up for vechicle air conditioning.

Re:R-12 Conspiracy

[runderwo]

I hear that there are properties of 134 that are just as eco-unfriendly as the original.

Such as what? It's a HFC which has zero ozone depletion capability, and it's non-toxic except by asphyxiation. Probably the worst thing about it is that it isn't a particularly good refrigerant, so compressors designed for R-12 are usually stressed more when retrofitted.

air instead of freon?

[WillWare]

Is there any reason not to compress and decompress air instead of Freon? You take air from inside the car, compress it thereby heating it up, then you run it (under pressure) through a long radiator outside the car. Once it reaches the temperature of the outside air, you decompress it (cooling it) and dump it back inside the car. This is the same principle that makes bicycle pumps heat up (and I'm guessing the same principle used with freon).

I know I'm not a genius, so somebody has already thought of using air, especially since air is so readily available. The fact we're not using air already means there is some problem with it. Is air inefficient for heat transfer?

Re:air instead of freon?

[Mongo222]

Yes, you can get cooling from compressing and then expanding a gas, but you don't get the ability to move nearly as much heat as when you use a material with a high termal co-efficent, and one that goes from a gasious state to a liquid state during the refrigiation loop.

Re:air instead of freon?

[Kevinv]

If I had to guess it isn't the heat transfer rate but the amount of heat air can absorb plus the amount of work it takes to compress the air.

air doesn't hold heat that well (even compressed), so to pull heat from the interior of the car you would need a lot of air (look at the size of the radiator used to distribute engine heat to the air. would you want even one half-size inside your car? Where would it fit?

Next, calculate under what compression 97 F air (current outdoor high temp here in Missouri) would have to be so that when expanded it would lose 25 degreess worth of heat. Air is realitivly incompressible, it takes a lot of work to compress it. My powered air compressor takes a lot of effort just to inflate my tires to a suitable PSI.

finally, i'm not convinced regular bicylcle pumps show a significant heat increase due to air compression, not to say there isn't any, just not enough to account for all the heat generated. I think friction between the handle and the walls of the pump may contribute more. Try with bellows style pump where there is less friction and see what the heat increase is there.

Article title...

[EmagGeek]

I have to take exception with the article title... it should be:

"Utah teens play prank on USPTO, win Patent w/ Junk Science"

Talk to the Germans - they have cold AC

[zerofoo]

My Volkswagen produces ice cold AC and does not use freon. It can get the car cold enough to condense water on the outside of the car's windows.

Most BMWs, Mercedes Benzs, Audis, and Porsches also have powerful AC units. Just because GM and Ford can't design AC units correctly does not mean that it cannot be done.

-ted

Peltier cooling for fuel rails. reubengathright.co

[Anonymous Coward]

I find the article interesting because it makes the inventors sound like the discovery was never thought of before.

I have been running a 300Watt Peltier based system on my Dodge Dakota for over a year now. The system cools my fuel rails down to about 70F or less (depending on ambient temps). The system has been proven to increase HP (you've heard it all now right?).

The concept is what should intrest other "inventors". My system pulls 30 amps and uses two water pumps. 30+ Amps is the load you will expect to cool any type of vehicle with today's TEC's.

For more details and pictures, please visit: http://www.reubengathright.com/DakFuellRailCooling Research.html

Thanks,
Reuben Gathright
Software Engineer, part time gear head.

P.S. The site is horrible on the eyes, I do not have research funding to spend on webdesign.

Not a new invention...

[Gnulix]

My father's company used to make similar peltier-based AC:s for use in mining facilities. It must have been 15-20 years ago.

Mythbusters

[Steve_Jobs_HNIC]

Today's cars use more gas at highway speeds if only one window is down compared to the air conditioning.

Yeap, Mythbusters did prove this theory wrong. 2 SUV's were loaded up with 5 Gallons of gas and driven around the track. One had the AC on and windows rolled up, the other had the AC off and windows rolled down. If I'm not mistaken, The first test was inconclusive. However, the next test I believe proved this theory wrong. They decided to fully gas up the SUV's instead of trying to accurately measure and fill up only 5 Gallons. The test showed (and I'm not sure on these numbers) somewhere around a 5% to 10% loss of MPG on the AC SUV. While the AC SUV had to pull over, the windowed SUV kept on trucking!! So yeah, they busted that myth.

Re:Mythbusters

[Suidae]

The initial test was done by reading the output of one of SUVs on-board computers to determine how much air the engine was using. This test was done at 55MPH with windows up and AC on, and with windows down and AC off. The data indicated that the vehicle used slighly less air, and therefore less fuel, with the windows up and the AC on.

The next test was to be a 55MPH run around the race track to determine which of the test vehicles would run out a full tank of fuel first. Safety officials did not allow this because of concern over tire failure (and possible subsequent vehicle rollover) and possible driver fatigue (maintaining the concentration required to handle the vehicle for the 6-8 hours required for the test would be difficult). Instead the test was run at 45MPH with 5 gallons of fuel.

The power required by the AC on full is constant regardless of the engine speed. The effect of drag on the vehicle is dependent on the speed, and the nearly 20% reduction in speed may have eliminated the slight difference seen in the first test.

Also, the fuel was removed from the vehicles using a hand pump, and it was not shown that any effort was made to clear the fuel from the in-tank pump all the way to the fuel rail in the engine. It is possible that the two vehicles did not have the same amount of fuel.

They did not show that other conditions where checked, such as identical engine parameters (the computers in modern vehicles tune themselves depending on how they are driven, if the two SUVs were driven before the test they might have had different computer parameters, resulting in different fuel consumption rates).

In short, the experiment was very rough, and had little in the way of controls. It is likely that at low speeds it is better to have the windows down, and at high speeds it is better to have them up. Also, it is unlikely that the AC would be run at MAX the entire time, so there would be fuel savings there as well.

The episode was entertaining, and did mostly answer the question "Would a big SUV use more fuel driving at 45mph with the windows open and AC off, or with windows closed and driver shivering under continious MAX AC?"

To test more accurately would have required several trials of the same vehicle at several different speeds with an accurate flow meter on the fuel lines (both delivery and return lines). Throttle position at all times would have to be carefully controlled to avoid any serious variations in computer tuning. Trials would ideally be run in two opposite directions, similar to how land speed records are controlled.

I can see the auto industry being VERY interested

[artemis67]

The kids bought the five chips they needed off of eBay for $50. The big auto makers should be able to buy the chips in volume for significantly less. The article doesn't say, but is that the biggest expense in such an AC system? I don't know what current auto AC systems cost the manufacturer, but I would guess that it's significantly more than $50.

Oh yeah, the auto industry would eat this up like biscuits and gravy.

real headline: "Mormons attempt coolness"

[thnmnt]

...and most likely fail in the effort.

The Sad Part Is...

[rAiNsT0rm]

The fact that no American company or investor could care less, the Japanese are the ones interested. We invent a product and because of our ties to oil we will never attempt to solve the issue or even help decrease our useages. The Japanese see it as a potential solution and a benefit and move on it.

I'm so tired of this crap in America. It isn't even political as both sides have no interest in solving these issues, they all have too much to lose/gain. A real shame.

(on a technical note though I'm not sold on the idea and the amount of problems to overcome are huge with this "solution")

Silly mods

[ichigo 2.0]

He's being funny, Germany and France are quite the opposite of what he claimed them to be. Or maybe the mods are trying to be funny? Hmmm.

Re:Doubtful

[qengho]

Someone should invent a rain-sensor, so cars can close their own windows if it starts to sprinkle.

Been done, actually. We visited Paris about a month ago and rented a car to drive to Normandy. It began raining on the way, and much to my surprise (and geeky delight) the windshield wipers came on automatically.

The sensor resolution was good enough to turn on at a light sprinkle, and the wipers adjusted their speed when conditions changed, e.g., speeding up when driving through the heavy spray of a large vehicle.

This wasn't a luxury rental, it was your basic minivan. I can't help wondering why this tech isn't on cars in the U.S. My wife teases me that the wipers were the highlight of my trip to France...

Carl Youngblood, we meet again!

[John Harrison]

What is your /. account name so I can friend you? I haven't noticed you on the blogs recently. How are you?

I saw that article in the Trib a few weeks ago and I thought it was pretty cool. (no pun intended) I hope that this goes into production, it sounds like a real innovation.

chips

[benoe]

Peltier is a chip. Chip is top tech. Top tech needs every other tech to exist. Therefore top tech is neither clean nor (environmentally) safe.

Questionable

[kkl]

First of all, peltier is essentially a forward biased PN junction, so if u look at a 1.5x1.5 sq inches block.. it's essentially hundreds of diode connected in parallel..
current draw is AMAZINGLY large... tiny block i have is about 1x1 inch, draws 4-5Amp at 12-15V.. (5Ax15V=75W),and that marely cool a small cooler i atttached into down about 10 degree below ambient...according from my friend's volvo user manual, the AC fuse was rated at 15A, that can feed 3 of these.. and i doubt it will cool the whole interier in the summer.
of course .. someone can modify the wiring and feed more juice to it.. but how many do we need is the question
and the heat are ALL need to release to surrounding... need some really serious heatsink there if u dont' want "another peltier to cool it down :p".
so.. unless someone has come up with a better peltier than the one we see in cooler and those desktop fridge.. i don't see how it will cool my stationwagon like the good old AC there.

more environmentally friendly.. definely.. cuz no freons. that's a plus.. must give credit to these 2 "young inventors"

Life time.. THAT i am not sure 30 years.. not sure what grade u are getting

Nix the "at 70mph " part. [NT]

[Chrispy1000000 the 2]

[NT]

Yeah, I like it better...

[skids]

....when the thermoelectric effect is used in the other direction.

Like here

Though Peltier cooling does have it's advantages/niches.

I hope it is reliable

[peter303]

I've spent a fortune repairing the refigerant style air conditioners over the years, a necessity living in the South. Theys have lots of mechanical parts and special fluids which are prone to failure.

Rent out Texas

[jbeaupre]

"If I owned Texas and Hell, I would rent out Texas and live in Hell." - General Philip Sheridan 1855

Seems you're not the first to suggest it'd be better to live underground.

Bad cow pun

[doublem]

That was cold man, really cold.

an other form of cooling...

[mrdogi]

I seem to recall perhaps 3 years ago an article here on /. about a newer form of cooling. It basically used electricity to carry heat through a vacuum "wafer" or some such. Does anybody remember that article? I've tried searching for it, but have never been able to find it....

Naturally, after trying again, Now I can. Nevermind

Insurance scales horizontally

[sheldon]

That is... in order to have an efficient insurance system, you have to insure everybody.

Specifically, the more healhty people you have in the system, the less the overall cost is per capita.

This is why the US system fails, because we only worry about insurance if you aren't healthy.

Oh Slashdot...

[JohnG307]

...and don't harm the environment with ozone-depleting freon like today's car air conditioners.

Wrong. "Today's car air conditioners" don't utilize Freon (R-12) for just that reason. In 1992, R-134a ( a more environmetally-friendly refrigerant) was introduced as a replacement, and since 1995, all new cars in the United States have used R-134a A/C systems, NOT Freon systems.

New AC

[Trtle_Nuts]

What's funny is that people actually believe that the auto industry in the United States will allow such a deep cut in the amount that Americans pay for gas. They want us to be as dependent on "gas" as is humanly possible. They went so far as to ignore the PHEV,(http://www.energine.com/eng/engine/engine2.h tm), developed by a South Korean company because it would have eliminated the need for gas.(They,U.S. automakers, asked if it could be modified to be a "dual" system using both air and petrolium) It just goes to show that when it comes to saving the environment, the automakers are not interested if it affects the amount of revenue they get from selling gas. Anyone who believes that the automakers will allow the use of anything in a vehicle that lowers our consumption of gas, (in this lifetime), is delusional, at best.

Re:New AC

[praxis]

I wonder what technology (and fossil fuels) are used to compress the air. I wonder how often the air tank must be refilled. I see this as being a technology of a lot of future potential, but how effective is it today in terms of automobile range, environmental impact on compressing the air vs. environmental impact on burning biodiesel or other alternatives, etc. The site compares their PHEV with a convential battery driven electric motor, but they're short on some critical data points for comparision, which to me is a red flag...or at least orange.

Freon is NO LONGER USED!

[turbotalon]

The poster said "...Ozone depleting freon..." Does he realize that R-12 has been banned since 1995? Thats 10 YEARS that R-12 has effectively been out of use. ALL new refrigerators, A/C units, etc run using R-134a since 1995.

This is a common misconception by the average consumer who does not educate him/herself. The current refrigerant (R-134a) does not destroy the Ozone layer. DO YOUR RESEARCH!

It is ignorance like this that helps all the wackos on both sides of the aisle out there take hold and gain power!

Leonard Who?

[Sir_Eptishous]

Al, you're one funny guy!

Ugh

[moogleii]

MythBusters is a terrible show. I think they could definitely stand to use some more consultation in their experiments.

Re:Peltiers

[Krystlih]

What is interesting about this article is that it states it runs off a second alternator that has to be added to the car. If this is the case then there will be an additional load on the car engine. If the load is less than normal car AC units and the amount of cooling power is the same, then the kids are right it will save gas milage. However how they tested that is not listed, will be interesting to watch though. Congrats to the kids.

Re:Peltiers

[JVert]

K.
Now that the pollution threat is seemingly lower and lower I think we are ready to compare the pollution in lost refrigerant vs extra gasoline used to power the peltier.

I think you mean energy consumed...

[YesIAmAScript]

Yes, the smaller unit takes less than 120 watts. Actually, it takes less than 40 watts.

But that's just instantaneous power.

Why does this matter? Because the cube fridge actually SHUTS OFF. When it reaches its target temperature, it turns off, it probably runs with a 5% duty cycle. The Peltier device works so poorly, it had to run constantly just to keep the device cold.

And again, the cube fridge gets much colder and cools an 8X larger space.

I don't think a cube fridge uses 1KW, I can't be truly sure, I don't have one here to plug into my Kill-A-Watt. Maybe I'll take the Kill-A-Watt to work and put it on a coworker's cube fridge. But 1KW is over half the power available on a regular 15A circuit, and I don't think that a 15A circuit will blow if you plug in two cube fridges to it (and they both come on at once). For that matter, I don't think my fridge in my kitchen used 1KW. But I can't find my spreadsheet with that info in it from when I measured it. Oh well.

Re:I think you mean energy consumed...

[stienman]

The average 1.8ft^3 fridge uses between 300 and 400KwH per year. They also specify a 15 or 20 amp outlet, though that is likely due to compressor startup.

The point you make about duty cycle is a good one, and I had not considered that. Of course, duty cycle directly affects your measure of performance - how quickly can you cool a 6-pack. If the compressor fridge operates for 5 minutes and cools off the cans in 10 minutes, then that is the same as the peltier fridge running for (given 5% duty cycle) 100 minutes, and cooling the cans off in 100 minutes.

Further, if you assume the fridge takes ~350KwH per year (look at the energy star ratings on websites such as whirlpool or ge) then there's a 1KwH per day consumption.

If you run the 40watt peltier all day (24 hours) then there is slightly less than a 1KwH per day consumption - meaning that they are roughly equal in energy consumption if your 5% compressor duty cycle and 100% peltier duty cycle assumptions are correct.

Now one would have to take these and measure their performance side by side to find out which one is better. Due to cost cutting (even with energy star compliance) compressors are very inefficient. It could be that the peltier cooler would compare favorably against one, but technically the ideal peltier cooler is incapable of comparing favorably with the ideal compressor cooler.

We are, however, dealing with companies whose main goal is to reduce cost. The peltier fridge is obviously easier and cheaper to make. The compressor fridges are not nearly as efficient as they could be.

-Adam

NIST cooler may be more efficient than Peltier

[MCRocker]

NIST has developed a cooler that uses the preferential tunnelling of hot electrons to cool a semiconductor (also reduces vibrations).

Since so many posters complained that the Peltier coolers in the A.C. described in the article are so inefficient, I thought I'd point out that there's a chance that this new NIST invention could make this sort of A.C. a more viable option than it is now.

Re:Young men, tinkering in garages, changed the wo

[lxs]

I know this looks like BS on the surface, but just possibly they had an epiphany no one else has had and figured out a better way.

To paraphrase a great man who passed away yesterday: "You cannot change the laws of physics"

Current Peltier elements simply aren't that efficient. And building a novel Peltier element (which is the only way to increase total efficiency) requires quite a bit more than two guys in a garage.

not true.

[YesIAmAScript]

You can get a 44 quart thermoelectric cooler from target.com. A cube fridge is 48 liters, which is 50 quarts or so. Thus they are very comparable in size.

Also note, as I noted below, that watts is instantaneous power, not energy. This matters because while a cube fridge will turn off most of the time, the Peltier has to run continuously just to stay as cool as it is.

I measured my house fridge (800L volume) with my Kill-A-Watt. Over 5 days, it took 5.8KWh. That's under 50W/h. So I can run my house fridge to cool 800L (1/3rd of which is freezer) for only 25% more power than this Peltier cooler, which can't even make ice in an 8L space.

Solving the wrong problem

[Once&FutureRocketman]

This invention follows a typical pattern: engineers (or would-be engineers) are so enamoured with their technology that they run out to solve problems with it, without first asking which problem they ought to be solving.

The majority of automotive airconditioning load is used to cool down cars that have gotten hot sitting, baking in the sun. There are very simple measures that automotive manufacturers could incorporate to cut down on that heat load: Radiant barrier material in the rooftop, low-e window coatings, and a small air circulation fan to exhaust the hot air that builds up in the cab when the car is parked.

None of these features are high-tech, and none would be particularly expensive to implement. Taken together, they would do a great deal to reduce the need for airconditioning, and contribute greatly to driver comfort (because the car would be cooler when you first get into it!). But they aren't sexy or high-tech, so they get overlooked. Of course, the peltier-based A/C system will almost certainly be ignored as well. The kids get accolades, but the technology isn't going to make it into actual production cars.

As Amory Lovins has said about the adoption of new automotive technologies: "Large automakers face two problems when trying to innovate -- they are large, and they are automakers."

Re:Damn yank cars!

[one_who_uses_unix]

We only use 4WD when weather/road conditions warrant. The MPG I cited was actually for 2WD mode (not sure what we get when we operate in 4WD mode).

That truck has an 8 cylinder 5.8L engine. I think that Chevy could get away with smaller displacement engines on these things. I bought it used so the selection was a little more limited.

I suspect that people do not realize the huge affect building a new car has on the environment. I think that by simply "recycling" cars rather than buying new all the time might help more than we realize.

Re:Young men, tinkering in garages, changed the wo

[gbulmash]

"You cannot change the laws of physics"

Before Galileo, the "law" was that different items of different weights would fall at different speeds. When Galileo proved otherwise, the "law" had to be amended.

What we call the "laws of physics" are merely best-evidence postulates to be held until better information comes along.

Many of science's greatest advances have come from men who "fought the law" and won. "You cannot change the laws of physics"

Keep repeating that. Perhaps if you say it loud enough and often enough, you can get a place in the history books as the fool who tried to discourage one of science's future greats from changing our understanding of the universe yet again.

Look at what we did in the last century...

We went from balooning to moon landings.
We discovered how to transplant vital organs.
We discovered new elements.
We split the atom.

And at some point there was a majority of someones who said the "laws" of science prohibited such things from being possible.

Einstein wasn't a professor in a university lab when he published his famed papers in 1905. He was a patent clerk, working on his papers in his spare time. At least figuratively, he was a young man, working in his garage.

If you want to say "improbable", okay. But when you say "impossible", you risk being history's fool.

- G

I drive a Honda Insight

[UCFFool]

Driving the Same route, day after day, Highway at 65mph, I've driven it with the AC on and I've done it with the windows all the way down (both sides).
Windows down is more efficient, hands down.
This would seem to contradict the theory's about a 'small engine' since it is just a 3 cylinder vehicle. Drag is the lowest of any production US vehicle, but regardless, would increase at the same rate as other vehicles as speed increases.

Re:I drive a Honda Insight

[Lumpy]

I have one also and saw the exact opposite.

granted barometric pressure, humidity, temperature and other factors make a HUGE difference in the readings.

but I notice that opening the windows my cruise control (yup you can add an aftermarket cruise to the insight) has to increase fuel to the engine to maintain speed.

I also notice that there is a difference in MPG (although disabling the DRL's made a bigger difference. that's 160watts right there)

also try running with 3-5 psi over pressure in your tires that also makes a nice difference after a tankfull.

Re:I drive a Honda Insight

[UCFFool]

I know about most of the mods for the Insight (active on Yahoo group and insightcentral.net) and even had the pleasure of driving the turbo insight (Willie's).
I also run at 45 all-around on the tires.
I agree a lot of things make a difference, being I'm in CO, and I didn't have a good testbed for when I was in FL (waaaay dif. climate).

Intel trying to sell silicon? :)

[Jan Brunner]

Some posters have already explained that the efficiency claims are definitely wrong. Thanks for that.

I was wondering why such a bad idea could win this competition and came to the conclusion that it has to be the silicon needed for the Peltier elements. This probably sounded familiar to the Intel guys or maybe they actually hope that this project leads to more silicon demand. :)

Have you ever heard of conservation of energy?

[Andy Dodd]

A car's alternator never "kicks in" - it's ALWAYS on.

The load it presents to the engine is proportional to the load on its outputs. If there's nothing connected to an ideal alternator, it will present zero load to the engine. (In reality, even an unloaded alternator presents a constant load due to friction.) As soon as you connect an electrical load to it, the alternator presents a larger mechanical load on the engine. (Usually equivalent to the electrical load multiplied by a constant which is the inverse of the alternator's efficiency. The efficiency of some alternators changes with load though due to the fact that alternators have to regulate their voltage output somewhat.)

The reason alternators provide no discernible (to the user) load on an engine is because the electrical loads they're driving are a small fraction of the engine's power. The largest automotive alternator I've seen was rated 120 amperes maximum. That's 1440 watts, which is on the order of 2 horsepower. (IIRC, 1HP is approx. 720-750 watts.) An A/C system alone uses more power than that. So, the system these students proposed combines an 80-90% efficient generator (the alternator) with a 10-20% (at best) efficiency heat pump, as opposed to an 80-90% efficient heat pump with a 99%+ efficient mechanical power transfer system. (The A/C compressor clutch.)

The Mazda 3 could use this

[lanner]

The Mazda 3 could use this -- it's air conditioning sucks!

http://www.mazda3forums.com/index.php?topic=25618. 0

Re:Hey shitehead...

[fishbowl]

>Not as much as the environment itself does, no.

So you won't mind if we use your drinking water source to store our mercury waste?

Re:Peltiers

[HermanAB]

No, it is always true. It doesn't matter which direction the heat pump is running. It cools at the one end and heats at the other end and if you reverse the valves, it goes the other way - in a car, there are no valves, so it only works one way, since it is more efficient to use engine heat for heating. Efficiencies range between 2.5 to 6 times the input energy - average about 400% efficiency.

Adapting the 1712 Newcomen steam engine

[newpath4comVersion2]

I fixed an engine (LN2000), later discovered the principle had been (sort of) used previously: http://tinyurl.com/c4ua4 . So my idea was original & wasn't that original at the same time! I think our inventions are starting to overlap. The Newcomen engine of 1712 engaged the power of an instantaneous vacuum to reset the piston for the next run. The Newcomen used the vacuum to pull the piston back while my adaptation works the other side, multiplying the power of the compressed air which explodes in the steam-filled cylinder. Issued a challenge to all nations yesterday: http://www.newpath4.com/opec_crude_oil_dilemma_or_ opportunity.htm . They'll read it in 2050. hehehehe

Re:Adapting the 1712 Newcomen steam engine

[Shanep]

I fixed an engine (LN2000), later discovered the principle had been (sort of) used previously: http://tinyurl.com/c4ua4 . So my idea was original & wasn't that original at the same time! I think our inventions are starting to overlap.

In 1989, while playing with some JK flip-flops configured as a ripple counter, with variable resistors connected to the outputs, I discovered Digital to Analog Conversion. Having never heard of DAC's at that point.

That was pretty cool.

Re:Adapting the 1712 Newcomen steam engine

[newpath4comVersion2]

1989 was a very significant year in Man's History. It never ceases to amaze me how many people had things happen to them that year. The Exxon Valdez went down, dumping 11-14 million gallons of crude into Alaskan waters. The Sun evaporated 5-6 million gallons of it which then traveled via the jetstream, becoming stuck to dust particles (seeding, gaining weight) til they began raining all over New England residents. I was in New England a few days later. Unbeknownst to me at the time I had been living with a rare thyroid disorder... SoI got poisoned with stuff my body & mind couldn't handle. By the time I arrived back in Virginia I went to unload my truck and, as I opened the trailer doors a bale of freight came after me. Thus began the last 16 years of my life and a new life of having spontaneous, sudden inventions. http://www.newpath4.com/fraudinauschwitzvirginia_w oodrowriley1989.htm & much more recent an update: http://www.newpath4.com/fraudinauschwitzvirginia_w oodrowriley1989_1975%2B2005_update7142005.htm . Not having an expansive knowledge of Science as many on here do have, I had to be really careful after "inventing" something "new" as it might have been invented earlier and I just didn't know about it... But, believe it or not, when I saw how to fix Hertzberg's air-powered engine by adding the steam, at that time I didn't know about the Newcomen Engine at all. It was only during the next months of researching to back up my engine solution that I ran across the Newcomen engine... hehehehe There is a notable difference tho, that his solution was on the back side of the piston while mine works on the active side. I guess a lot of people have been getting a good laugh about my use of natural forces to create a near-fusion kind of power without pollution. I think mostly because they thought it was a hack invention. I wonder if they'll continue laughing once they realize I used a working principle 300 years old. I also wonder if Newcomen has any relatives who will want ROYALTIES. hahahahaha 1989 again, a high school chum of mine also had an accident that next week. He jumped on an out-of-service forklift that wasn't marked out of service, went down the aisle with no brakes. He made the turn but his foot slipped off and was mashed beteen the lift side and a roof support beam. Part of his foot was amputated. You just keep on watching 1989. A lot of sh^t happened that year, and a lot of it I tie back to crude oil poisoning from the airborne crude oil molecules. btw while I'm here, I've issued a Riley Challenge to the Nations of this world: http://www.newpath4.com/opec_crude_oil_dilemma_or_ opportunity.htm . I know I'm not the most qualified guy to write that challenge but someone had to do it. We've got to stop scr^wing around. My main page now for my engine -the one that has most all the peripheral pages linked off- is http://www.newpath4.com/enginewow.htm . Friend, I admire you for having made that conversion circuit. I wish I could do stuff like that... but the accident I lived through plus the major fall from a truck I took in 1986, the 2 accidents almost erasing me, has left me with a difficulty of learning circuitry. It's quite sad actually because I have a number of ideas for devices I figured how to build, devices I could sell through hardwares & Wal-Marts everywhere, but I can't build them because of my learning difficulty. How I wish I had a partner who hadn't these issues. One of my inventions was for erecting a tubing structuure then filling it with chemicals that would harden. I finally decided since I couldn't do anything with it I would just release it into the SlashDot World so someone else would. Sure enough, less tha

15 amps is 1875 watts

[YesIAmAScript]

They specify a 15 amp outlet? A 15 amp outlet is a regular outlet. Why do you say it specifies a 15A outlet? Why should I care it specifies a 15A outlet? I've got one every 3 feet on the wall.

I'm currently testing (with my Kill-A-Watts) two fridges at work, one a 6L capacity Peltier and the other an approx 500L capacity regular fridge/freezer. (I wanted to use a cube fridge for the comparison, but my coworker got rid of his). I'll run them for 24 hours, but as of about 9 hours, the regular 500L fridge/freezer was on track to use about 1.1KWh in a day, and the 6L Peltier about 1.0KWh.

So the stand-up fridge uses about 10% more energy to cool 80X the space. Oh, and again, it is keeping about 1/3rd of its volume at below freezing, not 45F. And if you mean compared to a cube fridge, it's using 10% more power to cool 5X the space. And again, a portion of that area is not only well below 45F, but cold enough to make ice (freezing releases a lot of heat).

Also, I did dig up one thing, my home fridge, which has an 800L capacity used 5.8KWh of power in 5 days when I measured it a while back.

In your mention of the power taken by a fridge, the fridge I measured at work took only 145W when on, not 400W or 600W. I'm sure it takes a bit more sometimes, but not 600W.

When you say an ideal Peltier compares favorably, you are greatly mistaken. As you your comments about compressors being inefficient, you are insane. I've put a lot of numbers up there. How you can say that cooling 80X the space with 10% more power is inefficient I cannot understand.

I don't get your six-pack comparison. I'll say this, the Peltier will take 12 hours or more to cool a six-pack from room temperature to the 45F it rests at. The cube fridge wouldn't take over 3.

I'll have more numbers tomorrow, but to me, the story is already told. The fridge in the break room at work uses 10% more power than the Peltier in a coworkers office, and it cools 80X the space, and cools 1/3rd of that space well below the lowest temperature the Peltier can even reach at full bore. And I could put 10 of the Peltier fridges into the big fridge. I mean the entire Peltier fridges, not just the interior space equivalent. And I still would still have the freezer space to use for ice cream.

Re:Damn yank cars!

[one_who_uses_unix]

Thanks for the link. I love all of these vehicles that I see - they meet every need, except being able to seat 8. We have to move 6 kids and 2 adults - this looks like a great choice but only provides seating for 7. I am beginning to think that I am in search for a Holy Grail or capable, large capacity vehicles!

okay, the fridge race has ended...

[YesIAmAScript]

I measured the office fridge/freezer, a 500L or so unit against a 6L thermoelectric fridge. Both ran for 23 hours, 30 minutes (sorry, 24 hours ended at an inconvenient time).

The office fridge used 1.66KWh in 23.5 hours. That's 619KWh/year (non-leap). Although it would probably be a bit less than that because the fridge is opened less (and less cold lost) on the weekends.

The thermoelectric fridge used 1.50 KWh in 23.5 hours. That's 559KWh/year (non-leap). It would also be a bit less since the fridge isn't opened on the weekends.

Again, remember the full-size fridge is cooling 80X the volume, and 1/3rd of that space is kept at about 20F, not 45F. It also makes ice.

I still wish I could have found a cube fridge to compare. but that's life.

I personally feel this shows how incredibly impractical thermoelectric cooling is in fridge-sized applications. In a car A/C, which is much bigger than even the large fridge here, it is completely untenable.

Re:The problem is the power supply from the Altena

[Frank T. Lofaro Jr.]

They wouldn't pay for the extra control circuits or code if it didn't make a difference people would care about.

Heck they save money by making the body out of materials with the weight, cost, and strength of the average pepsi can (the car's body is a bit thicker tho :)

You consider 100 mph a cruising speed?!

You from Nevada or something? :)

Re:[Addaddendendumdum]

[zippthorne]

I was with you up to the news media comment. Perhaps I should remind of a little ship called the maine and the subsequent spanish-american war the fruits of which are with us to this day: guantanamo bay.

Riposte

[ishmaelflood]

My argument is rather more straightforward. It has already been done and is commercially available.

If you would like to discuss commercial terms try Air International, Melbourne, Australia

If you think it is a stupid idea as implemented, you are right. But the basic concept (solid state HVAC) makes sense.