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A comment on Cheap material converts heat to electricity. Parent comment

Re:Cheap material converts heat to electricity by grishka on Tuesday August 03, 2021 @07:39AM (#28048026)
When it was unusually hot over here, I was thinking about this. We can convert nearly every kind of energy into electricity and back. But for heat, for some bizarre reason, this only works one way. A lot of processes generate it, but you literally can't convert it into any other form of energy. You have to transfer it somewhere where it won't be as much of a problem.

It would be very nice to have an AC where you don't need to deal with that. I thought about many ways to get rid of heat without having to dump it somewhere, but thermodynamics is such a terrible thing.

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Re:Cheap material converts heat to electricity by wiredfool on Tuesday August 03, 2021 @09:16AM (#28048745)
Thermodynamics -- you can't win, you can't break even, and you can't even leave the game.
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Re:Cheap material converts heat to electricity by blueblisters on Tuesday August 03, 2021 @12:39PM (#28051245)
> I thought about many ways to get rid of heat without having to dump it somewhere, but thermodynamics is such a terrible thing.

This is likely a stupid question but temperature is a statistical property describing the energy of molecules right? Is there no way to tap the energy of the molecules for useful work without having a temperature difference?

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Re:Cheap material converts heat to electricity by davidinosauro on Tuesday August 03, 2021 @04:19PM (#28053646)
You might want to read about Maxwell's daemon [1]. I came across this a few weeks back, two links away from the HN homepage.

I found it intreaguing and read more about it but I can't quite umderstand the proposed solutions, likely due to my lack of background in thermodynamics.

[1] https://en.m.wikipedia.org/wiki/Maxwell's_demon

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Re:Cheap material converts heat to electricity by blueblisters on Wednesday August 04, 2021 @01:26AM (#28057540)
Clearly, Maxwell was much better (and funnier) in articulating what I was asking. Looks Maxwell's demon can work some of the time at a molecular level, but on average, you need to do work to extract useful heat from matter at a macroscopic level. The hypothesis being that you need to do work just to identify hot/energetic molecules from the cold/low-energy molecules.
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