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Hydrogen Micro Turbine Only 4mm In Diameter
savaget writes: "Luc G. Frchette of the Columbia University Microsystem Engineering Laboratory has developed a 20W electrical generator powered by a hydrogen turbine just 4mm in diameter. For more details, read the Wired
article or an older Popular Science
article. The tiny generator is more efficient than any battery and is expected to find military and commercial uses including robotics." Imagine the uses ...
That's 40 KHz.
Your dog is going to go totally nuts every time you turn on your PDA.
--Blair
Okok, I couldn't resist. I never do that.
But where does the exhaust go?
And isn't this kind of a step back in our attempt to stop using fossil fuels, or is it still a better alternative by the messes left by batteries in land fills?
"Old man yells at systemd"
How about a self powered mobo? Think self-powered, dual Athlon machine! Talk about a laptop that has some legs! How about leaving your flashlight on overnight and it still works the next night!
You must be the change you wish to see in the world - Ghandi
I wonder if this will find it's way into powering devices like laptops?
Shh.
Both articles say the engine is powered by fuel, but what fuel are we talking about? Regualar old gasoline/octane? Am I supposed to stop by the local gas station and top off my laptop battery each day on my drive to work? The Popular Science article mentions hydrogen being burned...maybe this means that they are looking for "alternative" fuels as opposed to fossil fuels. Then again, the Wired article hints at fossil fuels as the energy source. Someone shed some light on this please.
greg
Water would be the exhaust, just have a little vent.... but that still is kind of questionable, what if you plugged up the vent? I'm assuming there's still some more experimentation and design hurdles to leap before it's ready for commercial uses.
It looks like they're operating the generator in open air so exhaust isn't a problem..
Even if this burns an ultra-clean fuel, you're still going to have problems with exhaust and how to get rid of it.
Does this mean if I play quake on my laptop sitting in the garage I can commit suicide? Hmmm.
Seriously, now in addition to noise polution at my desk, I'll have to deal with smog soon?
I assume there's some sort of formula for figuring that out, could you share it with us.....?
One of my drinking buddies worked on a project similar to this. He told me that the heat problems mentioned in the article were the single biggest obstacle to making a successful mini-turban. Apparently researchers have been working for years on these devices, but they have watched as battery technology has advanced and their heat problems remained. Basically the main problem is that the intense heat generated by combustion places an upper bound on the lifetime of these devices, and that upper bound is substantially lower than the upper bound on a Li-Ion battery's lifetime. Back in the days of NiCd, shoddy "Renewal" cells, and expensive alkalines, this might have provided some much-needed competition. But for now it is just behind the time, despite the fact that it is so small.
~wally
Apparently it generates a lot more heat than a conventional battery. Too hot for a cell phone. New slogan:
"Reach out and torch someone."
-tim
You can bring it along with you in liquid form though, that will make it like a rocket.... umm... :)
By the way, the reason for usage in the rockets (yes, there is a rocket that runs on oxygen/hydrogen , called "Energiya") is that hydrogen is the most energy-packed element.
There was a movie at some time or other where they had an electronic bee, run by remote control. A tiny power generator could make such things possible in the not-so-distant future. Imagine how far we've come.
There was a discussion several days ago about batteries that are refilled with gas, rather than recharged. It sounds rather messy to me, while a system that uses a hydrogen generator certainly sounds cleaner and more efficient.
I wonder what kind of noise this system makes. If it is very quiet, we may very soon find that batteries in some of the higher end consumer devices are replaced by some mechanical generator such as this.
It may even be suitable for use in larger power generation scheme. Think of clustering a whole bunch of these tiny generators. Although they are currently quite expensive to manufacture, I believe that micromachines and nanotech will soon advance to such a level that it will be very possible to mass produce tiny machines.
Which brings me to the idea of tiny machines that have their own built-in hydrogen power generator. Now that's technology!
Oh well.
Is a gas-burning device more effective than a fuel-cell converting to electircity without any moving parts?
Or is it just easier to build?
Or perhaps just a technological challenge?
George
Atari rules... ermm... ruled.
generally does not make for the safest fuel source. Liquid hydrogen is *cold* (-400 F) and hydrogen in gaseous form tends to be explosive.
If you had a laptop powered by one of these, you would *not* want to drop it. If you did, you just might destroy your office.
Even if this were powered by some other combustible (such as gasoline) I'd have a hard time putting one in a child's toy, where it could be a fire hazard if the fuel tank breaks, let alone in a $2000 laptop.
From the Wired article: "For commercial use, the first application will probably be a battery charger -- if not actually in a laptop it could sit beside it," Frechette said. "Instead of having to get to an AC outlet, you can carry your power supply along with you."
This seems bass-ackwards to me. If the engine is in your laptop, it's "the battery" as far as a consumer is concerned. And if you run out of fuel in this engine, you have to get to a can of lighter fluid (or whatever), which is probably harder to find than an AC outlet (and relatively hard to get past airport security these days too).
If the first commercial application is a difficult, external battery charger, it will fail. Too bad, because small power sources have so many excellent possibilities. I hope this guy is a scientist and not a marketer.
You shall see a cow on the roof of a cotton house.
I wonder how well it holds up to being jerked around. I mean, would it be a good replacement for my CD player batterry if I'm going to go jogging with it?
Still, I'd love to have something like this that you could power with ethanol...
Why would anyone *want* a tiny hydrogen-powered turbine generator? Fuel cells are already more efficient than they are even hoping this will become; fuel cells also likely to live much longer since they don't have any moving parts.
I'll agree that it's cool to take things that we are used to at macroscopic scales and make them tiny, but it usually isn't going to be an efficient way of doing anything.
Tarsnap: Online backups for the truly paranoid
Luc G. Frchette
You forgot the accent aigu!
Shouldn't that be Luc G. Fréchette instead?
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Your source for commercial free 80's music!
What's stopping us from making a big generator out of a microturbine like this? Put a LOT of them side by side and you can get a lot more power per square metre of hydroelectric dam.
You get the added bonus of your turbines not eating fish, too. All you need to do is cheapen these tiny generators down below the price of a big turbine per unit volume.
"Look at me, I invented the stove!" -- Ben Franklin
Yeah, you might get a splinter!
You shall see a cow on the roof of a cotton house.
"The engine generates a lot of heat. Burning fuel produces heat that needs to be evacuated -- this means it won't replace the battery in all applications," Frechette said.
I could just see a run on hydrogen-powered cellphone HSFs in the coming years....
Didn't Nikola Tesla work on a turbine for a while? Basically it could be held in one hand and generate enough electricity to power a house.
--- even the safest course is fraught with peril
It doesn't get much press, but heat pollution is an issue in some areas.
At about one thousandth the size of a regular power station
I think that a regular power station is a little bigger than this (I would say 10,000 times - on a linear scale). If you consider volume, then it is many times more.
The power to volume ratio of this device is quite impressive compared to the regular power station.
Owl tried to think of something wise to say, but couldn't.
20W won't get your a dual athlon. I measured my Celeron 700 machine at 70W and a 1.1GHz Athlon box at 110W. Maybe 130-150W for a dual Athlon. You will need a little bank of 8 turbines to power the beast.
And about flashlight life... cockeyed has a series on "how much is inside". Checkout the battery one for a shocker about how much is really in a pair of D cell batteries. Then try to figure out why your flashlight is always almost dead. Who comes in and uses up your flashlight?
...can you power a Beowulf cluster with one of these?
Sorry...couldn't resist...
Hey dum dum,
This isn't efficient. Didn't you read the article???
Its one-thousandth the size but one-millionth
the power output of a power station.
They didn't create this for *efficiency*.
It was made because its small and portable.
Last time I looked water was not a pollutant.
So where do we mine the hydrogen from? Well, we don't, we get it (most likely) by running electricity through water and collecting the H2 off the cathode (if memory serves). But the key here is "electricty". Where does that come from?
Oh, burning coal, or fission, maybe...
The contaminants in gasoline would be far too great for a machine this tiny. Cars have huge engines that still get clogged up...
Hydrogen should be what fuels this nation and we should make that move as soon as possible. We have everything to gain and absolutely nothing to lose.
http://en.wikipedia.org/wiki/2004_U.S._Election_c
You need energy to produce hydrogen. It would not come from a coal burning plant, would it?
New windows errors!
No more stack overflows, now there are are engine overflows (flooded engines).
Boot up can be stopped by engine not starting.
And a crash could be a little worse than they are now...
I doubt this technology will actually be useful for small electronics. The power output is too unreliable, as are engines in general. Not to mention the volitility of hydrogen. Fuel cells have similar problems.
They'll really be good for portable applications that require massive amounts of power more than anything else.
Mod me down and I will become more powerful than you can possibly imagine!
I think that's a reference to the turbine size, 4 mm vs. 4 m diameter, not the entire physical plant.
For every complex problem there is an answer that is clear, simple, and wrong. -- H L Mencken
The article mentions the miniture turbines being much more efficient - could this help in making better hydroelectric or wind-based power generators?
A massive array of these on a windmill, or next to a dam would not have heat issues.
D: It makes you wonder how much of what he claims (or i guess what I've read about him, can't vouch for him that he actually said all of the crazy things about him) is actually true, and if there is a definitive Tesla site on the web... just looking for information on him and his ideas
Actually, I've found the single biggest obstacle to be working with those tiny pieces of linen.. I'm hoping nanotech will provide me with a solution in the near future.
Yes, hydrogen is abundant. But it is mostly tied up in covalent bonds with other elements, such as oxygen, in water, or some other such bound form.
To burn the stuff, you first have to split it from whatever it is bound to, and that takes some deltaE.
In fact, it takes as much deltaE to split the hudrogen off as you get back by burning it and puttign the bonds back together (first order calcs).
Hydrogen is a *storage* fuel. It is simply a new way to take energy from one place and move it to elsewhere, where it might be more convenient to use it.
If you plan on using hydrogen to create a lot of usable energy storage, as in to replace some of our curent fossil fuel dependency, you have to get the energy from somewhere. Like say, fossil fuel.
Or nukes, or some such thing.
The point is, it can't reduce our curent dependency on our current fuel sources (well, it might add some efficiency at sa few points, like al.owing us to use excess generating capacity at off-peak hours. The laws of thermo-goddamnics still apply.
Hydrogen technology doesn't create any new energy reserves, it simply allows us to store some of our energy reserves in a different (H2) and potentially differently-useful form.
I always thought his head was kind of small for regular sized turbans.....
So what happens when you spill some liquid hydrogen into your expensive laptop? Doesn't liquid hydrogen need/exist at a cetrain (cold) temperature?
I'm no expert, but I think the fuel itself could pose some problems. Anyone have more info?
US Democracy:The best person for the job (among These pre-selected choices...)
Most micromotors demonstrated to date have simply succeeded to overcome the viscous drag on the rotor, leaving no power to drive other com-ponents and limiting their use for low-load actuation.
Luc Frechette just published ASSESSMENT OF VISCOUS FLOWS IN HIGH-SPEED MICRO ROTATING MACHINERY FOR ENERGY CONVERSION APPLICATIONS in which he lays out the constraints of micro-motors and how he hopes to overcome them.
It is 1000th the linear size.
Therefore it is one-millionth the surface area.
Therefore it has the same power output per square meter.
http://www.thehungersite.com
That was the theory the fact is that no one has built a self sustaining model. The turbine you are thinking of is a bladeless design.
Got Code?
Better yet, and more American...
If this microturbine can be mass produced for pennies, like many other semiconductors, and eventually we can make a cheap aluminum tubule sandwich sheet that is thin enough to make cans...
We could make disposable self-cooled cans of Budweiser! Who wouldn't marvel at the combination of technology and wastefulness!
...of the microfan array for CPU cooling somebody was talkin about.
Now you'll ask what has this thing to do with a turbine?
I guess it's true for both of them that if they are in use they get dirty, no matter from what, enthropy is everywhere something moves.
I can imagine ONE turbine only 4mm in diameter is kinda hard to clean. What if you have to clean 100 or 1000? How easy can you reach it when it sits inside your laptop/nightvision/etc?
So, how useful are they?
A pyro's dream come true ;-)
Where do we get the electricty to get the hydrogen to seperate from the water?
We still are getting the majority of our power from fossil fuel burning and until more earth friendly sources of power are used, this is not a well thought out answer.
Computers are electrically powered anyway.. the same electricity used to charge a battery can be used to generate hydrogen fuel from water... I think this process uses less electricity than charging a battery so there is a net savings in electricity.
There are 10 types of people in this world, those who can count in binary and those who can't.
They should be trying to make turbines out of cheaper material, like AOL CDs. If your turbine breaks, its no big deal, because there's probably a new one waiting in your mailbox.
JET Program: see Japan, meet intere
The scientists' goal is to create an engine that will operate at 10 percent efficiency -- that is, 10 times better than batteries operate.
uhh... i thought that batteries were more efficient than internal combustion, which is at least 25% (as far as i know). are they actually claiming that a battery operates at 1% efficiency? i could have sworn it was closer to 90%.
anybody know differently?
I'm imagining a two bladder system: one under heel, one in mid-step with ducted turbines between. Step on the 'heel bladder', push gas through ducts for power one way, take pressure off again, suck gas back into chamber under the heel for turbines configured the other way, with one-way valves to regulate flow each way. Have an accordion pump where I can sit and 'pump-power' my laptop with my foot?
Dunno all the operating parameters involved for these micro turbines, just some thoughts...
There's no wrong way, to eat a Rhesus...
That, and now the "Turbo" switch on the front ofthe old machines will be literally accurate--instead of slowing down the machine for old games, it will kick in the generator and boost cpu voltage . . .
hawk
Or is this too complicated?
Being perfect to the last atom or so, there should be no vibration at the fundamental frequency. I counted 20 blades in the Popular Science picture, so the actual noise peak should be at 800kHz. Easily damped, and out of pet hearing frequency range.
> withGreenpeace/Sierra Club/NRDC..... Anything beyond a horse and
> buggy can't be good for you.
Ack! the dreaded dihydrous oxide! quick, ban it! for the children! It causes drownings, crop failures, and electrical fires . . .
hawk
2) There are 60 seconds in a minute
3) Hz is a measure of cycles per second
4) Simple arithmetic
If you knew those three things, you did know how to convert RPM to Hz. You were just to stupid to realize it."
Three things, huh? At least he knows how to count.
Hm. Heat + tank of hydrogen = never mind.
This is still one of the major problems of using alterative engery methods. I rember a while ago Chrystler made a prototype(sp?) Hemi Charger that ran on Hydrogen and it worked quite well. It ran very clean and made alot of power as it was supercharged. The only problem is the expense of the Hydrogen fuel. Perhaps use big floating solar seperaters?
Also a fellow I work with has built several cars that run on Methanol (sp?) as they can produce HUGE power gains. They also burn very clean but use twice as much fuel as a comparable gas engine does and the fuel costs about 1/3 more where I live. Oh well.....
Vote early. Vote often. Vote CowboyNeal.
No. My parents always had cats at home, and, as a teenager, I did a lot of experimenting with electronics. Cats do not mind sounds above 20 kHz (maybe they can't hear them?). They hate mostly the sounds between 8 and 12 kHz. Not coincidentally, that's the frequency range of the "hissing" sound cats make when annoyed or angry.
2.4 million RPM on a turbine that is 4mm in diameter... its math time... .3 miles per second for the metrically challenged. Very long range rifles shoot at speeds on that order of magnitude.
2400000 R/M = 40000 R/S
1 R = 4mm*pi = 12.56mm
40000 R/S = 502656 mm/s linear velocity
503 m/s is pretty fast. Thats about
I havent done basic physics in a long time so i am rusty on the formulas; could someone do the energy/force calculations for me? Just off the top of my head i think 1 milligram (thats the equivalent weight of one cubic millimeter of water, which i think would be about the right order of magnitude for the blades on this turbine) moving at 503 m/s could do some daage to organic tissue, more so than a splinter at least.
talk about influence of science-fiction on real-world-tech.
Well, at 500 m/s, the energy is 0.125 J (the formula is 1/2 * m * v = 0.5 * 0.000001 * (500 * 500)). Imagine a large human fist, weighing one kilogram. That fist would have the same energy moving at 50 cm/s. Would a large human fist moving at 20 inches per second hurt someone? And the energy would be concentrated in a millimeter sized particle, not distributed over a large human fist. Much worse than being hit by Mike Tyson. Let's fucking hope they SHIELD those turbines!
I think most power plants are bigger then four meters on a side...
autopr0n is like, down and stuff.
You may as well question, I dunno, the flavor of Applejacks or something!
Wow. Thanks dudes. Maybe I'll get my karma point back now. heh. I was thinking maybe that splinter could be something like a piece of hay in a tornado, but then I figured, ah hell, the darn thing probably just melts into a ball of redhot sludge, anyways.
That kind of efficiency is not what turbines have ever been used for.
Their advantage lies in their power to weight ratio.
Essentially you won't see fuel cells replacing turbines in helicopters anytime soon unless the power to weight ratio disadvantage is outweighed by a need for low noise or heat output.
A set of these things would be great to power a tiny helicopter for your smaller pets.
Why don't they dissipate that heat by transforming it into more electrical power?
It's called "entropy"
autopr0n is like, down and stuff.
...whether we can imagine a Beowulf cluster of these?
They used to put that stuff in 7up, untill it was discovered to be psychoactive. Now it's used to help depression.
autopr0n is like, down and stuff.
Louise, baby, try to finish your stories prior to Thanksgiving weekend next time...sheesh...
-- @rjamestaylor on Ello
Nah, don't count on that! Let's just hope the mod who got you down will be the one to get the first splinter! He will be looking (very closely) at the turbine, thinking "Hey, there's something burning in there, that's (-1, Flamebait)!" when the thing will blow up and the splint will hit his eye...
I'm always liked the idea of the solared power flashlight... too bad that'll never take off.
Illiterateracy can be blessing in cognito. You know how stupid it is b/c you posted it anonymously.. like the coward you are.
Carpe meam simiam!
Hook a bunch of these suckers up in the toilet tank. Turbines charge some cells. Next time you are in the bathroom, you've got enough free power to power a laptop, a TV, radio, refrigerator...
:)
Yeah, that's a bit sick. Maybe a small TV and a webpad though.
SIGFEH
They didn't say anything about liquid hydrogen.
autopr0n is like, down and stuff.
The turbine was etched into silicon. Like a microchip. How are you going to make one 'bigger' then what they had using the same techniques?
And certainly you could make turbines for cars, there's no guaranty that it would be more efficient or green or whatever. You can use gasoline with a turbine (in fact the article talked about using fossil fuels with that little thing) and you can use hydrogen for piston engines. Its really not that big of a deal.
And isn't like there is much hydrogen just floating around out there for use to use to power cars and stuff with, it requires more electricity to extract hydrogen then you do by burning it.
autopr0n is like, down and stuff.
Although the rotor is of small mass, I cannot help but wonder if gyroscopic effects would be noticeable with this device. With the rotor spinning at 2.4E6 RPM (40,000 times a second), I would assume there to be significant gyroscopic effects. Imagine impressing your friends as you ballance your laptop on your finger. Since the battery is slightly off-center, it would cause the laptop to rotate around your finger, too. Now I can finally join the circus and be a techno-geek too!
--- At my sig, unleash hell.
No, one can also consult reference materials, but this requires initiative.
(And sometimes one wants to learn something that nobody else knows. This requires even more effort. Imagine the state of human knowledge if the only way to learn were to ask someone else.)
Motorola Specs for PowerPC's
Linux capable and OpenBSD to boot!
http://www.sciam.com/news/101101/3.html This could be used to convert some of that heat back into useful energy.
-Pimproot, advocating Rube Goldberg machines in homage to car alternators.
And proceed right out the back of his head, it seems. A micro-lobotomy, if you will.
http://www.sciam.com/news/101101/3.html
As penance, I'll plagiarize some text for my honorable master, the slashdot audience:
Novel Semiconductor Device Heats and Cools on a Dime
[...] Rama Venkatasubramanian and co-workers, publishing in today's Nature, built a faster and more powerful than ordinary thermoelectric device, which converts heat and electricity back and forth, by alternating very thin layers of two semiconducing materials. This film-made of bismuth, antimony and tellurium-is 2.4 times more efficient than conventional bulk devices, 23,000 times faster, and can be applied in tiny dots for pinpoint refrigeration. "This marks a major advance in a field that has stagnated for 30 years," says John Pazik of the Office of Naval Research, which provided funding for the research.
Thermoelectric devices are longer lasting and tougher than mechanical refrigerators. Their high cost and low efficiency, though, have generally confined them to niche markets: powering deep-space probes, cooling infrared detectors, and, lately, heating and cooling luxury car seats. Cheaper, more convenient thermoelectrics could speed up microprocessors and fiber-optic lines, make possible miniature biotech tools capable of stopping and starting small biochemical reactions, or running a car's air conditioner with waste heat from the engine.
-Pimproot, betting his transplantable head on the Promised Land of scientific salvation
Water would be the exhaust, just have a little vent....
Water?
Try superheated steam.
I don't want a jet of THAT coming out of something sitting on my lap. B-)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
The backstroke?
--
Mod up a post Rob doesn't like and you'll never mod again
>Hydrogen technology doesn't create any new energy reserves, it simply allows us to store some of our energy reserves in a different (H2) and potentially differently-useful form.
:-)
Unless, of course, we find a natural source of anti-protons. Which is, I must confess, very unlikely
I got some questions that mayhaps some more imformed people might help me with. And they've probably been asked before.
- How the heck would you get a fuel pack small enough to be practical? From what I understand this thing runs off of hydrogen. Liquid fuels are of course more economical, so I'm assuming liquid hydrogen. Because making the fuel pack ultra cold would be impractical, I'm assuming they're conna use brute force (pressure) to make the molecules live nicely. I don't really know the properties of high quality metals/ceramics, but I think a reasonable guestimate would be...ohh, a pack the size of a laptop batter could only hold ~ a cubic centimeter of H2, and take most of its weight from the bulletproof container.
- Exhaust. I'm assuming the turbine is out to make water, if the fuel is H2. Easy to get the stuff from the air, but what would the product be? If it's steam I don't really see a problem, just vent it out the back of the laptop (a good application I think,) and be done with it. If it's liquid, what then? Have another container in the fuel pack that you have to drain every so often? (heh, laptop go pee-pee...yeah I know, real mature.)
- Heat. Why silicon? Sure it's realtively easier to manufacture the parts because as the article says, it's like making a computer chip, and that's been done to death. But wouldn't some stronger materials better address the problem? Something that doesn't warp under high pressure and heat. (I think something spinning that fast would make a lot of pressure, kinda like how harddrives need breath holes.) Of course that would be harder to manufacture...and going back and re-aligning all the atoms (so it warps evenly and in a way that doesn't break it) in the turbine would be a tad too hard.
- Why combustion? I think it might be worth it to look upon perfection and go biological. Make a fuel pack full of bacteria (how 'bout sulfer eaters? I'm sure they'd love to sit next to the CPU,) and an enzyme that'd take the bacterias' byproduct to turn a small spindle (circular muscles?? *shrug*) that's hooked up to a generator. Or maybe something to do with converting bioluminescent energy, or heck, even figure out how neurons shoot off electricity and do that. Of course the battery would run itself to death, and yes, you'd have to watch your battery work itself to death and buy a new one. Then again the bacteria could be made to hibernate when it lacks food, so it can be stopped & conserve fuel. Of course how would you flush all the end-products? (heh, laptop go poopie...yeah yeah, really mature, but it'd still be gross.)
So yeah...moo, that was a pleasant way to procrastinate doing homework.
--Roy
The author doesn't specify whether "regular power station" means hydroelectric or not, but if this is three orders of magnitude less efficient by volume than a regular large power station, it's exceedingly unlikely that putting a lot of them side by side would be a smart solution.
Of course, who knows how it would behave if the turbine were powered by flowing water rather than hydrogen combustion.
"Biped! Good cranial development. Evidently considerable human ancestry."
That's what they'd be good for. Not much else.
"Would it kill you to put down the toilet seat?" -- Maya Angelou
The exhaust is water vapor, unused combustion air, and heat. That shouldn't be a problem. Well, you won't want 20W to 40W of heat running in your pocket, but other than that it should be fine.
The 20-40 watts is the power delivered by the device to the laptop and eventually (except for a miniscule amount leaving as light, radio waves, telephone modem signals, etc.) disipated as heat by the laptop's circuitry.
But the generator is a HEAT ENGINE and this one runs at 10% efficiency. So to generate 40 watts it burns fuel at a 400 watt rate. 40 watts to the laptop, 400-40 = 360 watts of heat in the exhaust.
And you CAN'T improve it very much. It's a heat engine. Perfect efficiency for a heat engine is the carnot cycle limit: 100% * (Th - Tc)/Th.
Call that about 30% for a fuel-burning engine at room temperature, and you're still talking 133 watts of heat sitting on your lap for a 40 watt load. But you can't get anywhere near carnot cycle in a practical device, and the smaller and faster the device the more you'll fall short - you need something like a power-plant to approach it. So back to 10% and 400 watts.
What gets me about the Scientific American article is the apparent claim that the efficiency of batteries is ten times worse. Batteries and fuel cells can approach 100% efficiency.
I think what happened is they confused efficiency with energy density. A battery contains both its fuel and its oxidizer - and oxidizers tend to be heavy, due to heavy atoms and extra atoms to hold them down. Heat engines and fuel cells, on the other hand, can get their oxidizer from the ambient air, and expell the combustion products. So they only need the engine/cell proper plus the fuel tankage. Yes a heat engine would probably beat a battery by a factor of ten on energy density. But a fuel cell, if it can be adequately miniaturized, might do still better.
Nevertheless this engine looks like a good solution (if you're willing to put up with the waste heat), at least until fuel cell technology approaches it in power density.
The use of hydrogen is curious. Handling it is a real bitch. It crawls right through steel and burns with an invisible, super-hot, ultraviolet flame. Very dangerous.
They are probably using it, rather than a liquid hydrocarbon like butane, to simplify the design and to get the maximum energy-density numbers for the engine/tank system. With butane/air you need to do emission control for NOx, CO, and unburned hydrocarbon. With hydrogen/air you only need to sweat NOx. Hydrogen's energy/ounce of fuel is higher and it's easier to light. Liquid hydrocarbons - especially impure and "odorized" formulations - produce a number of combustion products that can potentially foul the engine or its exhaust as well. You don't need fancy controls for a hydrogen engine, while a butane engine might need a catalytic converter and some serious compute power.
What I'd like to know is whatever happened to the ceramic oxygen-concentration fuel cell - the one that uses the same basic cycle as the exhaust-gas oxygen sensor in a car?
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
... was Richie Rich. Yeah, the one with Macaulay Culkin.
*shudder*
God that movie sucked.
In a world without walls and fences, who needs Windows and Gates?
Safety. If are generating power in the most efficient way (instead of the CHEAPEST way with a complete lack of care given to the environmental consequences) you should agree that a central hydrogen generation facility using fossil fuels to generate its power would make much better use of those fuels than an automobile.
That is the entire point of this article. Why use a wasteful, polluting chemical battery that is extremely limited when you can use a miniature hydrogen turbine? Safety, Cleanliness, Efficiency, Common Sense, Your children's future.
http://en.wikipedia.org/wiki/2004_U.S._Election_c
... even if the H2 tank ruptures there is not going to be enough H2 to do anything. It might burn for a second or two and thats about it, most likely not enough H2 mass there to really do any damage (beyond the device it's in). Certainly not enough to cause an explosive misture in a large enough volume of air to matter.
Sorry, wrong answer. You're underestimating the size of the tank.
Existing lithium cells have "the energy density of a hand grenade" - and weigh about as much as one, so they also have about the energy of one. This has ten times that energy - look at the run time numbers. That's because it's using an external oxidizer in combination with tanked hydrogen. That means it's got a LOT of hydrogen - essentially a small tank of liquid H2.
If you mix the H2 with the appropriate amount of air to burn it efficiently you get the energy of ten hand grenades - call it a couple sticks of dynamite. If it leaks (without initially igniting) inside a building, it will light when it reaches lower explosive limit at a nearby source of ignition - a close approximation to the ideal mixture. The pressure will couple efficiently to the walls and roof, blowing the building apart. The superheated steam left behind will ignite the fragments.
If, on the other hand, it leaks and ignites, you'll have a welding-hot needle flame which is ultraviolet, and thus invisible, poking out some hole in your laptop or playing against something inside it. And it will burn much longer than a butane torch with the same weight of fuel and same flame power.
Meanwhile, hydrogen is a very small molecule and can thus flow rapidly through very small holes - like between the atoms of a steel tank. This means it's much less forgiving about the quality of your tankage, gas plumbing, and valves. Leaks are MUCH more likely to occur.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
right you are...
Hertz is the modern name for "cycles per second". It is the number of times per second that a wave passes a given point.
arrogant bastards, really. *snorts*
The way I interpreted the Wired article, this thing is still theoretical. They didn't even mention a working prototype. I refuse to read anything real into a Popular Electronics/Mechanics/Science article. That's all complete crap.
/. will instead be discussing the latest vapor being hyped.
I'm sure a couple years will pass and we'll all wonder what happened to that "micro turbine thing". We won't be discussing it much, though, because
Why are you letting these clowns ruin our country?
more like a piece of hay coming out of a railgun :>
If you split sea water, you can do it anywhere sea water is available, not just in the middle east. It is a clean process and can be done using nothing but solar energy. Or wave energy. Or whatever.
So yes, you have to expend energy to get hydrogen. It is in effect simply an energy storage vehicle. But the energy we need to do it is being beamed to us free of charge from good old Mr. Sun. In other words, it's a good way to take advantage of (and solve the problems of) direct solar energy.
That was a mistake. I was originally only going to list the first three, but added the fourth because you'd need to use simple arithmetic and if you didn't know it you couldn't. I thought that I had changed the 'three' to a 'four' in both cases, but obviously I missed one.
I suppose you should be extra-careful not to make any mistakes when criticizing someone for stupidity or whatever, but I do hope that you realize the difference between a typo and sheer, unadulterated, idiocy.
autopr0n is like, down and stuff.
Turbines improve in efficiency with size. That's why modern aircraft have two huge engines, instead of eight small ones like a B-52. It's also one reason that automotive turbines have never really worked.
An interesting story..
A few years ago when I used to be a SysAdmin for U of A's Chemistry Department, I remember one morning coming into the lab and seeing a group of grad students huddled around an SGI terminal, where the teacher was giving a demonstration. The demonstration was of a "hydrogen ion engine"..One of the faculty researchers within the department had managed to successfully model the tail section of a spermatazoa using a 3D molecular modeller we had. After giving a short (somewhat technical) explanation of the atomic structure of the tail, he demonstrated how the "motor" of a spermatazoa tail works. The sperm absorbs hydrogen ions with its head, and passes them through its body to the tail section. The interaction of a single hydrogen atom with a portion of the tail section causes the entire base of the tail to whip around 360 degrees, like the crank shaft on a car engine. The simulation was played, so that the students could see how hydrogen ions were absorbed, and essentially turned into fuel for the motor housed within the tail of the sperm.
Keep in mind, this wasn't a "simulation". The software being used is an atomic modeller and conformation engine designed to run on supercomputers that costs a hefty $15,000 per license. It was quite a feat to completely reconstruct the tail of a spermatazoa out of individual atoms and have it function exactly as it does in nature.
Cheers,
Bowie J. Poag
Thanks. I learned something!
US Democracy:The best person for the job (among These pre-selected choices...)
Some people are simply better then others.
If he wants to leave and never post again, the better for me. Untill then, I will bitch about whoever I want whenever I want.
autopr0n is like, down and stuff.
(similar issue with fuel cells, too, for that matter.)
-dB
"It if was easy to do, we'd find someone cheaper than you to do it."
Are you sure about that? Unless you have 2 or more sample points for each wavelength, the crest and trough of the wave sort of get "blurred" together into one sample. So if you sample at 44100Hz, you can't reproduce waves above 22050Hz.
(Do not sign anything.) -- Fell, Planescape: Torment
The tiny generator is more efficient than any battery and is expected to find military and commercial uses including robotics.
Does that mean we'll see an upgrade with this for Mindrover?!? Woohoo!
http://www.execpc.com/~teba/main.html
Harnes the "problems" of fluid viscosity!
Bob-
The Ludwig von Mises Institute. The reasoning individuals economics
(from previous articles on overclocking) As you use the compressed hydrogen gas, the container would get colder. I remember an article about a person using a jet engine to burn massive amounts of fuel in order for the fuel can (in water) to cool the beer. Heh. Jet engines, Propane and beer. Which is more dangerous?
So... you get power and a cold source for finally OC'ing those laptops!
make Linux, not Microsoft. sin(beast) = -0.809016994374947424102293417182819
Hydrogen cells are not any more dangerous/messy than the conventional LiIon/NiMH/NiCad bateries we're used to.
You will have a laptop that is hydrogen/miniturbine-enabled. What happens when your batteries run low? There's not going to be a 'gas tank,' there will be a regular battery-sized pocket that is removed/replaced. Snap one fuel cell out, snap another fuel cell in. No mess, no danger.
If you were in an 800 degree fire, would you rather have the laptop with the LiIon or the hydrogen cell? You know what? It doesn't matter, you're dead anyway!
What happens when you through away a traditional battery? What would happen when you throw away the hydrogen cell? It would be a lot easier/safer for the hydrogen cell to leak itself empty than the conventional battery.
Jason
One common misconception is that gas==gasoline; most of the rest of the world gas!=gasoline but more likely natural gas aka methane. So rather than messy this is far cleaner than refuelling your Zippo - more akin to fuelling those gas powered soldering torches
Evil ZEN Scientist
Wassup ?!?!
...
Speak up, I can't hear you. Is that a chainsaw in the background ??
No, it my phone!
If it will burn hydrogen, it will probably work just fine with butane or lighter fluid, too. It would be great to run my laptop for a week from a 5oz can of butane.
Even better, if it could burn methane we could charge gas canisters from home gas supplies. We'd probably need a pump to recompress, but that's no big deal.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
It was in New scientist (no link available, sorry). Engines like these are needed in joints of exosceleton. Other solutions (backbag engine or batteries) are not viable.
Anyway, it is not fruitful to shootdown good research just because nobody can't come up with application in a second. The question why anyone wants tiny hydrogen-powered turbine generator will be definetly ansered in future.
-- Nyri
The only reason that remains significant is that Fuel Cells still, generaly, require much cleaner fuels than turbines.
Any contaminants can reduce the efficiency of a fuel cell significantly, whereas only a significant build up of 'sticky' contamination will effect a turbine significantly.
"It is dangerous to be right when the government is wrong." --Voltaire
what kind of heat problemsdoes one deal with when making a mini-turban?
well, if countries were serious, the could simply not tax Hydrogen Fuels, that would help bring the price in line.
Also, I understand to build dual (Dino-Gas/Hydro) cars is not a problem, the problem is safely storing enough hydrogen (fuel cell) in the car.
-- www.globaltics.net
Political discussion for a new world
To pardon one for asking is unnecessary and frivolous. What you should ask pardon for, my vocabulary impaired friend, is introducing your pent up emotions and limited language to an otherwise reasonable discussion! Really you should consider asking someone where the library is. Lots of good words and REFERENCE material there!
Maybe I'm making the comparison too simplistic, but your car needs to be repaired long before the battery needs replacement (Even here in WI), so why would you put an engine into everyday devices?
Batteries = No Moving Parts = No breakdown.
"I can't give you a brain, so I'll give you a diploma" - The Great Oz (blatently stolen sig)
But this particular turbine requires hydrogen for it's fuel. That's the same as the ideal fuel cell fuel. And quite easy to clean, if you can handle it at all. It will pass through a filter fine enough to take out oxygen.
I think we've pushed this "anyone can grow up to be president" thing too far.
Brazil uses (used?) cars powered by ethanol (natural alcohol). Petrol cars can run on this with out too much modification. The alcohol was produced by fermentation of sugar cane, presumably the low-grade stuff you get after molasses has been extracted. Thus there was little enviromental damange; just the extra land and fertialiser used to grow more sugarcane.
It has become appallingly obvious that our technology has exceeded our humanity. --- Albert Einstein
nuff said
Sometimes I wish I was a plumber, then I'd know how to deal with other people's shit.
As I ran the math earlier on a post a couple of weeks ago, you'd need thousands of square miles of ocean for creating enough electricity to satisfy, for example, the US yearly demand.
I don't know about you, but covering thousands of square miles of ocean surface seems... unwise.
Go with nuclear, cause everything else just sucks more.
If the fan were going to make 40Khz noise, that would indicate that there is a process which takes on the same configuration only once every revolution. This is not the case here; the system looks the same 12 times every revolution. So the sound produced is at 480 KHz.
Your orchestra example is also bogus. If you were to take the sound of a violin playing one note, and layer on 11 more copies of the same sound, all being out-of-phase with each other by 1/12 cycle (which is what we have with the fan), you would *not* hear the original sound. You would hear the 12th harmonic of the volin, and all multiples thereof. In DSP books, it's called a comb filter.
I have a positive modifier on Troll. When I mod someone Troll their karma should go UP!
/.
Generally one pumps it through cooling baffles into the atmosphere. Then, of course, you have to manage the condensate drip.
It's an excellent question, and one that will have to be answered before this thing can see practical use.
I'd like to see what the actual generator design will be - all I see in the articles is a motor, not any sort of electrical generator.
This motor is interesting as pure research. I'd have done a bladeless turbine (if I could manage to get paid for doing stuff like this) but that might not be as much of a challenge to build and thus less interesting on grant applications.
I haven't seen anyone proposing any commercially viable use as yet - without a generator, ignition system and waste gas management scheme it's just a cool toy.
--Charlie
What gets me about the Scientific American article is the apparent claim that the efficiency of batteries is ten times worse. Batteries and fuel cells can approach 100% efficiency.
Oops. I meant "the Popular Science article".
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Nonetheless, the turbine tip speeds *are* "high subsonic or low supersonic" according to Frechette's papers. The turbine housing can reasonably be expected to damp external noise quite a bit.
[
Luc Frechette's publications page has links to a number of papers with more technical details on his work (including the reasons why hydrogen was chosen, the current status of the turbine, what happens when one of these rotors "crashes" (i.e. not the death of the researcher), and other details ignorantly speculated upon by slashdot readers. Start with the overview paper; you can access his PhD thesis and more details on many of the component parts of the turbine from his publications page.
[
If it's truly "more efficient than any battery," then why does it generate so much heat?
Efficiency is a measure of the fraction of stored chemical energy that ends up getting turned into useful electrical energy (as opposed to waste heat energy).
If it's more efficient than a battery, than for every watt of electrical power generated, there should be less waste heat than a battery would generate.
And another thing: I can't just go down to the store and buy a cylinder of hydrogen fuel. But I can go down to the store and buy a cylinder of butane. Could they make this thing more useful by tweaking the design to make it run on butane?
That that is is that that that that is not is not.
one thousandth the size of a regular power station
I would have thought power stations were a bit larger than that... I guess that's what happens when you write articles at 2:00 a.m.
I wonder what happens to the room (or an aircraft cabin) when everyone has one of these things and is 1) burning off oxygen and 2) generating a lot of heat
Given this thing needs a supply of hydrogen, and some air, why not use a fuel cell instead?
At least a fuel cell has no moving parts, and doesn't need to be 'perfect' to work. Plus instead of generating heat, you get pure water - which might actually be useful in say, an aircraft
Also, would have thought the fuel cell H+O -> power would be more efficient than the engine's H+O -> heat -> motion -> power
Will this engine-on-a-chip need a cooling fan?
hawk