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Company Claims New Chip Converts Heat To Electricity
Dster76 writes to tell us that the startup, Eneco, has invented a solid state energy conversion chip which they claim will be able to convert heat directly into electricity or reach temperatures of -200 C when given an electrical current. While such a device could revolutionize many aspects of computing I'll keep my skeptic hat on for the time being.
Solid-state device that converts heat to electricity....
;-)
http://en.wikipedia.org/wiki/Thermocouple
Invented 1821 - Prior art?
gus
P.S. Yes, I know that TC's rely on a temperature differential, not just a temperature...
.. if only.
I think Peltier coolers have been around for awhile now.
http://en.wikipedia.org/wiki/Peltier_effect
yes, The reverse is a well studied application, though the materials used are slightly different for optimal current instead of optimal temperature difference
ok.. so heads you lose tails I win. right?
I read the article and it says you need a heat sink! I was hoping this damn think broke the laws of thermodynamics!
Nobody doubts it can be done, see Peltier. They're not terribly efficient (I thought they were 15% efficiency capable, but I guess not..)
Dupe from at least 2002. Both the slashdot article and the technology.
There is nothing that this chip could do that could not be done by simply making current designs more efficient. In fact, the use of such a chip necessarily wastes energy.
In Soviet America the banks rob you!
A few years ago (6 I believe) a company called Cool Chips LLC (which was traded on PinkSheets.com back then) claimed to have done the same thing. Unfortunately outside of the first round of announcements (which may have even been on Slashdot), nothing more was mentioned. In the comments back then it was hypothesized that an energy conglomerate or oil company would buy Cool Chips out to keep the technology from ever coming to the market. Me wonders if that might have happened, or if some of the primaries from Cool Chips are now a part of this venture.
Memories become legend, Legend fades to myth, and even myth is forgotten by the time that age comes again.-Robert Jordan
See wikipedia for more. Seebeck is the reverse effect.
No, you misunderstood. There are two apparent functions that are totally separate:
1) Extract heat and use heat differential to generate electricity.
2) Use electricity supply to cool down to -200.
Either one or the other, but not both at the same time.
This does not violate the second law of thermodynamics. What it does is turn a heat differential (i.e. two objects of different temperatures) into a source of electricity as heat flows between them. Its purpose is to make systems more efficient- for instance, your laptop produces a lot of waste heat, and if we could recapture some of that lost energy it would improve your laptop's battery life. It also has the reverse effect of pumping heat (like an air conditioner) when electricity is applied to it.
You are reading a copy of my copyrighted post.
There are thermionic devices already around, you're probably looking at one. Vacuum tubes and CRT's are thermionic devices. Not very powerful ones--a typical tube only boils off microamps of current at under a volt, while requiring several watts of electrical power to heat the emitter. Not very impressive.
I read part of TFA but it just sounds like a better thermocouple.
Show me a production, working product. Otherwise, I'll wait for someone to come up with a way to 'catch' entropy.
This sig isn't original enough, it's time to come up with something witty...
What? No you wouldn't. Ever heard of... Well, a freezer? That's a device capable of turning electricity into a temperature differential, and as far as I know, doesn't break any laws of Thermodynamics. It's called a heat pump. The device in TFA can also act as a heat pump, probably using the Peltier effect.
What's purple and commutes? An Abelian grape.
It's called a Peltier device, and has been around for decades.
c t
http://en.wikipedia.org/wiki/Peltier-Seebeck_effe
According to the laws of thermodynamics, the conversion of heat to other forms of energy requires access to thermal reservoirs at two different temperatures, and there's a limit on the possible efficiency of the process, which is 1-T(low)/T(high). Their press release doesn't seem to be claiming anything that violates this, so it's not obviously voodoo science or anything. However, any such heat engine is only going to be useful when (a) you have cheap access to hot and cold reservoirs, (b) the temperature difference is fairly high, and (c) the efficiency of the heat engine is superior to the other practical heat engines that you have to choose from, or there's some other practical reason why this particular heat engine is better for your application.
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The problem is that converting heat energy directly into electricity violates the Second Law of Thermodynamics, not unlike perpetual motion machines. Thus anyone claiming that they can convert heat into electricity is lying, stupid, or discovering new laws of the universe. What this device does is convert heat differentials into electricity- similar to a steam generator, but without the moving parts. In order to make electricity it needs something hot on one side of it and something (relatively) cold on the other. It makes electricity while heat flows through it.
You are reading a copy of my copyrighted post.
Something just sounds fishy about this; like a scheme to power your car with it's own exhaust.
No, you can't run your car that way, but you can use the exhaust to turn a fan to turn a compressor to force induction to increase power.
Well call this a "turbocharger."
KFG
If someone told you they created a solid state device that could convert light energy directly into electrical energy would you believe them? Yeah, probably, because you have seen these in action already. They are on just about every calculator out there now. But there was a time when they were just an idea and the topic of fiction. The notion of using heat is so different? Surely the technology is quite different I'm sure, but I would not be quite so quick to be skeptical.
The Earth receives high energy, low entropy photons from the sun. It reradiates low energy, high entropy photons back into space. These reradiated photons are not very useful in a 300 K environment, which is in thermodynamic equilibrium with them. This is similar to how you'd find it much harder to extract work from sunlight if you were on the surface of the sun, an environment in thermodynamic equilibrium with that light. (Yes I know everything would melt you nitpickers but the point remains.)
The reason those calculators work is because they are exchanging energy with the sun's surface and they are not in thermodynamic equilibrium with it. On the earth's surface, if you try to make a solar cell to catch low infrared from objects on our own planet, you'll find that your cell radiates away the photons you are trying to capture, just by being at room temperature.
On deeper reading of this I see that they've "solved the problem" of maintaining a vacuum by "replacing the vacuum with a properly selected semiconductor material". (The reporter seems to have hashed things up so it's hard to be sure what they're talking about - as usual. B-( )
That sounds like they're trying to build a semiconductor equivalent of the true-vacuum device I described above. Perhaps something like a field-effect transistor using bulk, undoped, semiconductor material for the "vacuum" and perhaps a schottky barrier junction (or a doped region) for the "thermionic emission cathode". A "P-I-P" diode perhaps, with the thermal agitation lifting the electrons from the potential well to launch them into the undoped region?
(I should stop guessing and look up their patents.)
Much of the heat conduction in solids is done by electron motion rather than mechanical vibration transfer. So a bar of undoped semiconductor should be a better insulator than the heavily-doped P and N type silicon that makes up the structure of a peltier cell, leading to higher efficiency in a "semconductor thermionic" device.
Darn. I thought these guys were working on true cold-cathode vacuum tubes at integrated circuit scales, and had solved the three big problems blocking them (cathode construction, ion erosion, and maintaining a clean vacuum).
Vacuum tubes and their close relatives, gas-discharge (plasma) tubes, have great properties (like radiation and EMP resistance) and can do a lot of amazing stuff - some of which semiconductors still can't do, or do well. It was mainly the need to heat the cathode that let semiconductors displace them - and the strucutral shrinkage and continued breakthroughs that let them hold their lead. While the size of the electron wave function means nano-scale vacuum ICs will probably hit a density wall at a slightly larger feature size than semiconductors, vacuum ICs still have a lot of potential. If somebody had solved those three problems I mentioned I can imagine a partial revival, with vacuum ICs leveraging the semiconductor manufacturing processes and displacing semiconductors in at least some applications where their properties give significant advantages.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
HAH! Found it on their web site!
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way