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Car Powered by Compressed Air
gripperzipper writes "CNN reports that a Korean company created a small car powered by compressed air. ENERGINE created its PHEV, or Pneumatic-Hybrid Electric Vehicle, which uses a two-stroke compressed air engine for start, acceleration, and uphill climbs. The car switches to an electric motor when its speed reaches 20-25 km/h (32-40 mi/h). Although major auto manufacturers have invested heavily in gasoline hybrids, it will be interesting to see if a market will open for this type of vehicle." Update: 04/04 17:18 GMT by T : Reader Tapsu spotted the incongruity here, writing "Interesting post, but the speed conversion has gone wrong way: "20-25 km/h
(32-40 mi/h)". ... Thus the correct speed range in miles would be
something like 12-15 mi/h."
I hope it has an external refil port for the compressed air tank. This will be a great way to take advantage of stations that offer "Free Air" (and also, unfortunately, prompt a decrease in the number of stations offering "free air"...)
But does it take more electricity to compress the air into the tank than it does to just run the car on electric power? Sounds like just another degree of separation from energy we'll be getting from oil, anyway.
It would be cool if it didn't suck.
...this thing is gunna be loud.
Quid festinatio swallonis est aetherfuga inonusti?
Africus aut Europaeus?
Havn't they had something like this comercialy avalible in France for a while IIRC? Its has a ridiculously strong carbon fiber airtank that's presurised at home by a compressor using off the grid electricity. Its basically a small comuter car, but it has decent range and speed.
"Sic Semper Tyrannosaurus Rex."
This website provides the perfect fuel for this car.
But I'm probably just repeating the first several dozen comments...
I hear they're almost as volatile as tanks filled with explosive refined hydrocarbons!
The car swtiches to electric when it reaches 25 km/hr according to the Energine website which is actually more like 15 miles per hour.
From the manual:
"Should you find yourself approaching the state of being in an accident, please yourself to duck so as to avoid looking at your previously attached body before the shrapnel took off your head." (Safety tips, Appendix A, P.232)
Want to improve your Karma? Instead of "Post Anonymously", try the "Post Humously" option.
Here is another take on the same story, but with a little bit more science. The bottom line is there's no such thing as free energy... or lunch. You don't get owt for nowt. CNN needs to learn science
First off, like someone said, that the energy it takes to compress the air can be inefficient and still polute the air if the energy to compress came from fossil fuels/coal. Secondly, while it is an "Engineering Marvel" to drive up a hill using compressed air, it's very dangerous. For any of you who have ever worked on high pressure AC systems, any pressure higher than 500psi or so can be deadly if anything at all goes wrong. It's not like a battery, where a little acid can spill if it's broken. Nor is it like gasoline, cars are built to prevent explosions, and the worst case scenario is lots of fire. If you puncture a high pressure tank or lines, you have a disaster on your hands; theres no avoiding it. Besides, the entire problem with a gas induction engine is that they are horribly inefficient anyways unless they are running at their optimal RPM.
Now we know why this car keeps crashing into Mars.
This technology will never go anywhere. I worked on a liquid nitrogen powered car at UNT, which is basically the same as this thing except the nitrogen can be stored more densely when it liquifies, at moderate pressures. Expanding the nitrogen requires a rack of heat exchangers on the roof. However, since all the energy is stored mechanically rather than chemically, the Joules/Kg is about 40x lower than than of gasoline. It's even less dense than batteries. About the only market for this technology would be indoors where exhaust fumes are not allowed. But an electric vehicle would do better.
Our car was a VW bug, had 9 hp, got 1/3 mpg in the summer, and once reached 30 mph.
I believe they are actually rather more dangerous. Compressed air tanks are inherently prone to explosions when damaged. You get a little hole in your petrol tank, you'll lose your petrol and run a risk of fire if you catch a spark. A hole in a compressed air tank equals instant explosion.
Remember, life isn't like hollywood, not every car crash ends in a massive petrol explosion (or four... how many tanks do they keep in those cars?), but these compressed air tanks sound like shrapnel waiting to be flung.
In my (unsucessful) haste to be the first to point this error out, I missed pointing out the cause of the problem. There are roughly 1.6 km/mile. To convert km/hr to m/h, divide, do not multiply km * 1.6 (20*1.6=32).
What changed under Obama? Nothing Good
Man, this gives a new meaning to the phrase "passing gas" ;-)
The high pressure tank in that vehicle is charged to 300bar, or 4350psi.
That's higher than a SCUBA tank and it requires some heavy duty air compressor rigs to charge it.
I'd hate to be anywhere around that car in a crash or if it catches fire...
It switches to electric at 25, what happens at 80?
There are french cars that run completely on compressed air around for years.
http://www.gizmo.com.au/go/3523/
slashdot, wake the fsck up.
This compressed air engine isn't directly related to a environment-friendly fuel. The fuel of the car itself isn't compressed air - it's electricity, the battery. Electric cars, or hybrid cars, have the problem that they can't obtain high torque instantly. However, compressed air does give high torque. The idea is to store compressed air in a tank, and use it as a booster when high torque is needed. The air will be compressed later on with another compressor.
Now, combine the compressed air engine with an hybrid car. You get an hybrid car with instant high torque when needed.
This is old news. The Frenchies have been there and done it.
It's even been tried in African (same company).
The company's own website seems to have gone. I would be suprised if this wasn't because the company has also gone out of business.
Why does it only get on Slashdot when it's an American company?
Philip
Signatures are broken
They are far safer in a fire, too. If there is an overpressure in the cylinder, the gas is slowly vented, where it burns. With a petrol tank, as the fuel heats up the pressure rises until the tank bursts (because they're either plastic or thin steel).
We had great news of this kind in Europe exaclty one year ago, but at the end card didn't show up in our roads. News in Italian: http://www.ecotrasporti.it/eolo.html
Site of the company in English: http://www.theaircar.com/Lucerne.html
You forgot the real reason -- that it looks like (after 40 years of speculation), that we may finally be at Peak Oil may have finally happened -- and that we might be in for one of the largest societal changes in the history of man.
Religion is a gateway psychosis. -- Dave Foley
The line should read:
The car switches to an electric motor when its speed reaches 20-25 mi/h (32-40 km/h).
If the Toshiba announcement about a better traction battery is correct. Electric motors can have practically an ideal torque/rpm curve, but the current demands for high starting torque are a problem. The holy grail is a battery which has effectively an enormous surface to the electrodes without corresponding fragility, and so can be quickly recharged and discharged. (Traction batteries currently have a long service life but relatively slow charge and discharge. Starter batteries have a fast discharge for starting but are fragile and do not deep discharge well). Such a battery would completely supersede the inefficient compress air/decompress air cycle. So whichever compressed air tools division of this Korean manufacturer came up with this job preservation scheme - forget it and retrain as battery engineers.
Panurge has posted for the last time. Thanks for the positive moderations.
the dude that invented that vehicle (Guy Nègre, whom that I talked to at the paris car show a couple years ago) received death threats from unknown people that called him at night and stuff...
Imagine what could be done with an advanced plastic tank that deforms in a severe vehicle crash or other incident, instead of shredding like a metal one. For an added safety measure, should a puncture occur, an inner membrane flows out of the hole(s)like a balloon. As the membrane's volume increases, so does the potential force of the explosively escaping gas decrease, correct?
Materials keep improving. I doubt the ones I've speculated upon do not already exist. As to weather they're readily available to manufacture at a realistic cost is another question.
"OH SHIT, THERE'S A HORSE IN THE HOSPITAL!"
I can spot posts on the net at least from year 2000 about Mexico city running taxis and public buses on compressed air.
Am I missing the point ?
Z.
A completely compressed air vehicle has been made before and is a production model called the air car by a company MDI in italy. They have produced models for street use, you can see a video of it here.
...and it should be known by now
I've seen a 50kg piston moved a fair way with a small portion of a bottle of compressed helium just like you would use to blow up balloons - it was the first stage of a shock tunnel producing mach 15 shock waves for scramjet model testing. You can get a lot of energy out of a tank of compressed gas - you just have to put a lot more in there to start with.
When an electric car is standing still the motor does not draw power. Converting energy expended while braking into compressed air has been done on normal trucks and busses for years. Converting the batteries stored energy into compressed air is gaurenteed to loose some of the energy in the conversion and therefore will not last as long. Every time you convert energy you loose some so it makes sense to save the wasted braking energy. There is nothing really "new" about this car except they have taken a common fuel saving technology used on heavy transport fleets and applied it to an electric car. If it works for an electric car it would work for a normal car but with electric cars you can't just get a bigger fuel tank.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
[ A hole in a compressed air tank equals instant explosion. ]
Err, no. A hole of any size equals a leak and a loss of pressure. I am not sure which science friction books (pun intended) you have been reading but I have suffered many leaks in high pressure air tanks and in only one case was it dangerous. That was when a friend dropped his tank on the side of the pool and the regulator valve broke off and the tank left the scene rapidly. The type of gas was irrelevant as any high pressure tank would have taken the same trip. Do you think we would be allowed to strap these things to our backs if they were as dangerous as you say?
Petrol vapour on the other hand is very explosive so even an empty petrol tank can explode.
I love stacking my barbecues in the shed at the end of summer - you can't beat a bit of grill on grill action.
I spent yesterday afternoon farting about with a Air Hogs Firestormer. The plane makes a faring noise which adds to the fun we had!
I hadn't the slightest objection to his spending his time planning massacres for the bourgeoisie... (P.G. Wodehouse)
It might be cheaper for them, and cheaper for us initially (the cost of purchasing the car), but in the long run, it's definitely going to cost us more. As someone stated, it's another degree of seperation for the original energy source. Instead of using the electrical energy directly to drive the car, we're using the energy compress gas. Anyone who's taken physics understands that there will be energy loss for every energy conversion due to heat loss, friction, etc.
In other words, we might be paying a couple thousand less that an electric car, but it'll come back to bite us when we need to pay more for electricity to drive the same distance an electric car can. of course, there's not enough statistics out there to show how much more electricity is required to drive a compressed air engine. that would be something interesting i'd like to see.
i would also like to see some other statistics such as the top speed it can reach. how far it can drive before it needs to be recharged. last i heard, electric cars can usually drive about 100 miles before needing a recharge, but that was a few years back and battery technology and engine technology should have advanced.
another good statistic would be how long it takes to recharge. i'd actually like to see Toshiba's One-Minute-Recharge Li-ion Batteries applied in this field.
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One of the real dangers with current petrol engines is that they pump petrol to the engine at high pressure to meet sudden increases in demand (acceleration) and then pump the excess back to the petrol tank. This means that there is a lot of high-pressure petrol travelling around the car and when an accident occurs the risk of fire is much higher than 20 years ago.
On the other hand petrol tank design and placement has received a lot of consideration and is no longer such a danger as it was 20 years ago. So it is no longer the large tank that presents the major danger but the system itself.
I could not find a link but several years ago on the A40 in England there was a multi car accident in which most people died in the resulting fire rather than the crash. All the petrol gets dumped on the road and all the cars burnt. People could not escape in time especially those in the rear of 2 door cars.
Pressure of a propane tank at 100 deg F is 175PSI - this is a pressure that can be easily managed.
Take note too, that any major pressure loss on a propane tank will instantly drop the temperature of the remaining liquid in the tank (as it boils), resulting in less pressure - check a Pressure-Temperature chart for propane sometime.
Compressed air at a few thousand PSI is a lot more trouble to deal with in an accident.
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
It's the MDI Air Cars "The world's cleanest cars", developed by Guy Negre.
It doesn't use any fuel at all, only compressed air, and the features are good:
Weight: 750 kg
Maximum speed: 110 kmh
Mileage: 200 - 300 km
Maximum load: 500 Kg
Recharging time: 4 hours (Mains connector)
Recharging time: 3 minutes (Air station)
Someone mentioned the problems of having a (scuba) tank of compressed air sitting in the hot sun...yes, it can be a problem, obviously, if the air heats and expands above the pressure rating of the tank. I am assuming they thought of this and would make the tank adequately strong. (With scuba, the shop fills your tank to the limit, and then the hot sun gives you another 1000 psi and your burst disc goes. This is less than the five-thirds working pressure they push your tank to when they hydro it--I'm sure the tanks on the cars would have some kind of overpressure relief like a burst disc.)
The French air car article points out, "In the case of an accident with air tank breakage, there would be no explosion or shattering because the tanks are not metallic but made of glass fibre. The tanks would crack longitudinally, and the air would escape, causing a strong buzzing sound with no dangerous factor."
Well.
It's great to know that it's a carbon fiber tank so it won't turn into a screaming cloud of schrapnel, but isn't there another issue at work here?
Now, I don't know exactly where on that tiny car the tank is, but I'd assume it's under the seat someplace.
The volume of that car is what...two cubic meters? What happens when you instantly put 90 cubic meters of air inside it? (Or under it?)
Have a look at this rather larger car for an example. Look, ma! No fragmentation thanks to a steel tank, but all that air introduced to an enclosed space jiffy-pops a car like a cheap paper cup.
I'm more than willing to admit there's more to carbon-fiber tanks than I know. Maybe there's some property that prevents them from releasing all that energy in less than, say, 10 seconds, no matter how badly crushed. But I'm officially skeptical.
They say there's enough energy in a scuba tank to lift a hook-and-ladder fire truck 20 meters in the air. That's exactly the sort of energy I don't want released near me in a short timeframe. Gasoline is good in comparison because it doesn't tend to do this when the tank is ruptured.
Then again, a compressed air tank explosion might be just what I need to get ahead in today's Bay Area traffic. Up yours, Fastrak!
It's not about energy, it's about power.
_O_
.|< The named which can be named is not the true named
Yeah -- I've been watching this guy for a couple years, and have come to the conclusion that he's a complete con-artist.
If you read the website carefully, you'll note that the specifications he displays here http://www.theaircar.com/models.html for the various models (range, top speed, refuel rates, etc) are all based on theoretical measurements made by guessing how much improvement he can get from changing a number of things in his current design. The current design has been tested for a total of 7.2 km. He gets his 200-300km range by extrapolating based on his guesses. See http://www.theaircar.com/tests.html (scroll down to "Mileage comparison between the taxi in development and the final car") for the true specifications, and note that after the top row, they're all extrapolations. He's basically saying he should get x% increase from this change, and y% from that change, and that means the "improved" engine will get (x+y)% better performance.
His site hasn't changed in at least a year -- meaning those figures haven't been updates with actual test results, and I don't think they ever will be. It's real easy to guess how much improvement various changes may make. It's not so easy to get that improvement out of them.
Next, note that he's selling "licenses" to build factories to produce the car. This is his real goal: Grab some $$ from investors before they find out he has no real product. He's a lot like the guys selling free energy based on concepts that violate the laws of thermodynamics, but will have a working model "real soon now".
Go ahead and watch this guy -- it's entertainment at least, -- but don't give him any of your money until he can back up his specifications with real world tests.
Help find a cure for Gidget.
From a purely pragmatic perspective: I prefer a nice (nearly) pollution free city full of air/electro/whatever cars to many hundreds of stinking cars driving by my house every few hours.
So it's not totally green. Agreed. But it's a start in the right direction.
In my opinion midsized communal heating power stations are a good step forward to make that happen. They burn the fuel more efficiently and use the excess heat too. They come in ranges from 20 to 300 kW and cover most types of smaller to midsized buildings. They can even be used as a central power/heat station for a small residental area.
So, the pollution gets relocated BUT at the same time the system gets more efficient.
Meme of the day: I browse "Disable Sigs: Checked". So should you.
I was in a east-european car (Shkoda) when the gasoline pupm exploded, causing the back of the car (where the engine is located) to burst into flames. I was sitting at the back seat, with my parents at the front. I didn't hear it explode, but my father said he did. We just saw the car slow down, my father pulled over, I turned my head back and saw the flames through the back window, opened the door and, following the example of the brave Rincewind, ran my ass off forward. My parents stepped out of the car, the inflamable parts of the engine burning, stopped another vehicle and used a big fire extinguisher to put the fire out (we were lucky that the fire had melted one of the back lights, so they used the opening to spray the fire-extinguishing stuff inside).
Well, the car didn't explode, although it was filled up with gasoline just a few minutes before the accident. The back part of it (where the engine was) was badly burned, but the tyres, the seats and everything else was intact; maybe that has something to do with the fact that the fuel tanks are at the front of the car, under the front seats. Major parts of the engine had to be replaced, as well as new painting was needed. But we were towed all the way to our destination, and we had to leave the car for one year at my grandparent's yard. The car is still in motion today. I can't remember the exact year that happened, but it was easter, and it was sometime at the beginning of the 90s. I guess that made us all a little religious.
Then, of course, I could show off showing the molten back light to my peers.
The engines of large trucks (think 18 wheelers or similar sized cabs) start with compressed air, and have been for years. You know those air guns that service stations use to tighten/loosen lug nuts on car wheels? Same idea, just use that instead of an electric starter. Next time you're standing near a truck when the driver starts the engine, you'll hear it plain as day.
Never hit your grandmother with a shovel, for it leaves a bad impression on her mind...
No not "engine brakes", I realise they piss people off at two in the morning. The system I am talking about was implemented on busses in South Australia in the early 90's.
The "air" in a Jake brake is exhaust and, as you say, is limited by the compression ratio of the engine (not to mention choking it). The system I saw ran off the drive shaft and engaged when you hit the brake so the engines compression ratio was not a limiting factor. The inertia of the bus was used to drive an air compressor that in turn slows the bus down (ie: the compressor rather than the engine was "Jake"). When I saw the system I thought it was a good idea and assumed it had taken off, maybe it didn't, maybe it died because of cost/benifit. Popular or not the idea is nothing new, so put the "WRONG stick" down before you hurt yourself.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Petrol vapour on the other hand is very explosive so even an empty petrol tank can explode.
Actually, if you want a petrol tank to explode it pretty much has to be empty. Liquid petrol does not burn, drop a match in a completely full tank and it'll go out. Drop one in a tank of a petrol vapour/oxygen mix and you'd better be running...
We've talked about an aircar here before. The Korean model is a hybrid, this one the Aircar just uses the compressed air tank.
One perceived advantage of compressed air over batteries is that it can be refilled a lot faster than a battery bank can be recharged.(yes I saw the exception those new lions mentioned with the one minute recharge, that's pretty recent though). Some others are the tank itself is significantly lighter than batteries, probably much cheaper to make as well and doesn't have a lot of toxicity to it as batteries do. Another would be cycles of filling, I wouldn't expect it to wear out near as fast as batteries would.
All these various designs and techniques have plusses and minuses to them. Sort of like the early computer days with a plethora of hardware and differing OSes, etc. One of my pet ideas for this deal of having a high mileage cleaner car is to have a pure electric for the commuter car part, for extended range on trips just attach a trailer where a small diesel generator is located, turning the car into a "hybrid". That way most of the time you don't need to be hauling around two motors inside the vehicle, which the hybrids do, the electric motor and the fuel burning engine. Most of the time it could be recharged at your house overnight, ready to go back in the morning, and if you combined this with some solar panels at home (whatever alt energy do dad you like), it would eventually get to pretty cheap per mile to drive. You could "store" your juice during the day while you are gone back into the grid in those places that mandate netmetering, or have your own battery bank at home to plug into.
Comment removed based on user account deletion
25 km/h = 15.625 mi/h, not 40 mi/h
Guess someone goofed up on the metric system once again :)
Neocons are children who don't want their toys taken away, and won't clean their room because it isn't fun.
Thank you for recognizing that the distinction between the present domanant "neo-conservative" group think party in the US and true conservatives. True conservatives wouldn't have bought the toys in the first place (we're compulsive savers) and wouldn't have let the room get messy for fear of unspecified adverse consequences. True conservatives (I know, I am one) are more likely to avoid doing things because they are fun (on the principle that the more atractive the lure, the more likely it is to be bait).
--MarkusQ
Forget about the energy benefits/costs. The greatest benefit of this technology is that the vehicle should have zero emissions. This would lead to improved air quality in cities, since the dirty energy generation plants can be moved elsewhere, reducing smog and improving lung health.
Neocons are children who don't want their toys taken away, and won't clean their room because it isn't fun.
That doesn't describe "neocons", that describes about 99% of the world's population. Which do you think is more effective - appealing to their self-interest, or pissing and whining about how they don't see things your way?
Downmodding is the refuge of the weak. Don't downmod, make a better argument!