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If only we had thermocouples with solar panel like efficiency...

• lr1970 5y ago
  > If only we had thermocouples with solar panel like efficiency... Thermocuples are still heat engines converting thermal energy (heat) into zero-entropy energy (electricity in this case). Second Law of Thermodynamics limits efficiency of all heat engines as per Carnot theorem [0]. No free lunch (aka perpetual motion machine of the second kind) [0] https://en.wikipedia.org/wiki/Carnot%27s_theorem_(thermodynamics) https://en.wikipedia.org/wiki/Carnot%27s_theorem_(thermodyna...
  • SigmundA 5y ago
    Not looking for perpetual motion only a compact solid state heat engine on par with others in effciency that would allow a small nuclear battery to work without the steam engine complexity issues. The mars rover uses a RTG that puts out 2000 watts of heat and only 100 watts of electricity. Get it to 20% efficiency like solar panel and you're talking 400 watts, 40% like a steam engine would be 800 watts.
• toss1 5y ago
  Exactly - and for about a million other purposes also! This [0] seems like a good survey - some progress is being made raising the efficiency into the mid-teens... [0] https://www.intechopen.com/books/green-energy-advances/thermoelectric-energy-harvesting-basic-principles-and-applications https://www.intechopen.com/books/green-energy-advances/therm...