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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
Hydrogen isn't a fossil fuel.
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
Hydrogen is hardly a fossil fuel; it's abundant, and the combustion byproduct of hydrogen and oxygen (the two fuels used in this case) is none other than water. Pure water, at that.
This is why hydrogen is being looked at so heavily as an "alternative" fuel source -- it's abundant, clean, and very inexpensive.
--
I Hit the Karma Cap, and All I Got Was This Lousy
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
The "exhaust" would be water and heat. The heat can dissipate on its own if there is a enough surface area, and the water would be only in trace amounts.
The small amount of hydrogen (per device) to manufactured would have less environmental impact than the alloy and chemical production for lithium battiers. Would be lighter too, no more 10lb. dual battery dell laptops to lug around, hopefully.
"Get them before they get....
Burning H2 leaves you, surprise, water and heat.
Last time I looked water was not a pollutant. But you better check with Greenpeace/Sierra Club/NRDC..... Anything beyond a horse and buggy can't be good for you.
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.
"But where does the exhaust go?" - well, out, that is rather the definition of exhaust. 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.
"And isn't this kind of a step back in our attempt to stop using fossil fuels..." - I am an American. My goverment has no such policy. All your oil are belong to us. For those of you in conservation minded countries, hyrdrogen is not a fossil fuel. It is a theoretically handy way to store electrical energy. There are technical hurdles. Not insurmountable, just insurmounted. Once there is a demand, there will be a way of distributing and storing the hydrogen.
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
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
Ahh, Hydrogen! How stupid of me! I read the article, honest, but didn't catch that it was powered by Hydrogen. Thanks for the knock upside the head, y'all. :) Obviously, it's time to go home.
"Old man yells at systemd"
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?
And noise pollusion .. this thing can't be totally silent, for all ears of all species?
Heat pollusion is definately a concern for areas with sensitive ecosystems. Good point.
"Old man yells at systemd"
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?
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
H2 in gaseous form is NOT explosive unless it's in a mixture with O2 where it is about 4% to 85% of the mixture. Pure H2 is perfectly safe. And 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.
And since this tank is gonna be small, it can be made really freakin tough. Think about how tough a good quality propane cigarette lighter tank is.
As has been mentioned elsewhere, the byproducts of the hydrogen engine are water and heat. Putting it right on your "self-powered" mobo would greatly increase the heat output which would mean some of that power would have to go to additonal cooling fans/pumps... and then, of course, there's the issue of the water vapor being vented in close proximity to the electronic circuitry.
Separate the motor from the mobo, and you have a conventional device, with a gas tank instead of a power cord.
Any sufficiently well-organized community is indistinguishable from Government.
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.
Fission would be just fine. About as clean as it gets.
Liquid hydrogen is cold at 1 atmosphere of pressure. You can make it as hot as you want, if your container can handle the increased pressure.
Gaseous hydrogen isn't really any more explosive than the butane in your lighter or the natural gas piped all over your house.
You prefer children playing with toys powered by batteries that are packed with lithium, mercury, etc?
"Prefiero morir de pie que vivir siempre arrodillado!"
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!
Surprisingly, industrial hydrogen production does not make use of hydrolysis. It is actually not cost effective, when compared with other chemical reactions.
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
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
Shoot, just consider weight alone.
The plant where I work has two 1180MW steam tubine generator sets. Each one has moving parts that weigh in at about 800tons, thats 1.6E+06 pounds. Thats a lot of pounds. Compare that to this little (admmitedly very cool) device.
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
... or solar or wind power, or tidal power, or fusion, or any other power source that mankind figures out how to harness in the next million years. The cool thing about hydrogen is that it allows us to disassociate the method of power generation from the machines that use the fuel. Electricity has already done this for stationary appliances--your television doesn't care whether it's running on electricity made from coal or fusion. Hydrogen promises to give us the same flexibility for vehicles and fuel storage; that way, every time a newer, cleaner method of power generation comes on line, we don't have to replace every car and generator in the world.
Think of hydrogen as the XML of fuels.
I don't care if it's 90,000 hectares. That lake was not my doing.
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.
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.
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!
You may as well question, I dunno, the flavor of Applejacks or something!
Louise, baby, try to finish your stories prior to Thanksgiving weekend next time...sheesh...
-- @rjamestaylor on Ello
But the combustion byproducts of hydrogen and the oxygen in air are water and NOx and other nasties depending on what else is in the air.
Lars T.
To the guy who modded me down from perfect to terrible Karma - Apple haters still suck
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...
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.)
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 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."
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
There are ecologists, environmentalists, and conservationists.
Ecologists are scientists studying the way life interrelates. Systems analysts, really.
Environmentalists are people that try to limit damage to the ecosphere by indifference, greed, or maliciousness.
Conservationists, like the Sierra Club, are not necessarily either of the two above. They are usually more conservative, politically, and don't have the fire of the environmentalists. They compromise; they support hunting; they can be both a backpacker and a driver of an SUV.
Notice I ddin't mention the Greens. They are environmentalists that are really pissed. And I can't blame them, really.
... 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
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?
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.
Yes he did. But it rotates at a VERY high speed - high enough that the centripital force on the working fluid matches the pressure difference between the input and output ports. Tough to balance. Lots of friction between the gas and the outer housing to create inefficiencies. Enormous forces in the turbine material itself.
Bladed designs have proven more practical for general use.
Even there there's an interesting instability problem: The shaft has a resonance - the frequency it would "ring" in the oscilatory mode where the bar is beneding up at the ends and down in the middle. When the turbine's rotational speed approaches this resonance it pumps energy into it and tends to tear the turbine apart. The trick is to provide support that can damp this vibration for long enough to get the rotational speed up beyond the magic rate.
This design seems to sidestep the problem by flattening the turbine into a pancake.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
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.
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
You wish. Actually, burning hydrogen in air generates some NOx emissions. Hydrogen in air is a complicated combustion system. NASA has been working on scramjet designs that burn hydrogen in air, so this problem is gettimg some attention. It's the subject of some big number-crunching simulations.
If you want a totally clean burn, you have to burn hydrogen in pure oxygen.
Not to mention all the other waste that everyone wants NIMBY, and the feds have been trying to force on Nevada for, what, twenty years?
As opposed to fossil fuels, which send their pollution into everyone's air? At least nuclear waste can be carted away from MBY, to somewhere like Nevada, where they seem to have a pretty expansive view of what consists of their BY's.
__
Do ya feel happy-go-lucky, punk?
You are of course correct. I was only thinking of a pure H2 O2 reaction during my post. I suppose since the atmosphere is about 80% Nitrogen, any high temp combustion is going to bump into plenty of Nitrogen and cause several strange species to be produced.
Hats off to ya.
It's not PC to note this but did you realize that all the fuel from 40 years of operation of a nuclear plant will fit into the same volume as a large semi-trailer?
That's incredible really.
Imagine, all the electricity needs of a family of four for 40 years generate about 3 pounds of fuel waste.
(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."
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!
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.
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.
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.
[
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?
"The space occupied by the actual fuel cells might very well be in the order of a semi, but there are other types of waste generated from a nuclear plant also ("dirty" tools, clothes and spare parts among other things)."
True, but such lowlevel waste is divided into "burnable", and "meltable". The burnable pile volume is by far the larger (by several orders of magnitude) and the volume is reduced by specially licensed incinerators by 99.9%. The meltable can be deconned down to remove what realy has to buried and again reducing the volume by a large amount. Also, all that concrete and steel from the civil structures is buried in a regular landfill after the top inch or so has been removed and carted off to a disposal site, in effect a gross decontamination. It's way cheaper that way.
Just think about the ENORMOUS pile of coal ash generated by only a year of operation of a comparable sized coal plant, and that doesn't include the compustion gases mass that is directly released to the atmosphere.
I still stand by my position that a properly designed and operated fission power plant is by far the cleanest, most environmentally benign way of generating large bulk quantities of electrical power.
hawk
Actually it's water plus heat, and heat plus oxygen plus nitrogen -> NOx, and heat plus various nasty components -> nastier stuff. Glad to be of help.
Lars T.
To the guy who modded me down from perfect to terrible Karma - Apple haters still suck