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I'm NOT in any way a physicist, I just had This Idea which obviously can't work but I just don't see WHY it wouldn't work!

Get a container full of water. Use electrolysis to separate it into hydrogen and oxygen. Hydrogen burns in oxygen. Use a thermoelectric generator (TEG), to convert the heat into electricity, syphon off a bit of the electricity to keep the electrolysis battery charged and use the rest of the generated power. Now if you burn hydrogen in oxygen you get water. Can't we just use that water to restart this cycle, getting out some energy over and over?

Something tells me I'm missing Something Stoopidly Obvious here, which you experts will tell me in Words of One Syllable, but I'm up for that. Please remember I'm NOT a physicist, just a disabled guy with an Idea or two, so be nice with the techieness of the answers! (You can call me an idiot, just be nice about it!)

Yours respectfully,

Chris.

David_h
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ulrichburke
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1 Answers1

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There are a couple of reasons this wouldn't work.

First, the amount of energy needed to separate Hydrogen from Oxygen in water will be the same amount gained when they recombine to form water (the burning part) - meaning any heat gained is actually energy gained back after you invested it in electrolysis. Second, converting heat to electricity or any other useful energy source is limited by the 2nd law of thermodynamics which says something like this: it is unlikely (to the point of impossible) to turn 100% of the random motion energy in heat to a "more ordered" form used to do work. Meanibg not only you got the same amount of energy from the burn as you put in, you can't get it all back as useful energy to do work and repeat the cycle.

Hope this helped!

Ofek Gillon
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