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Re: Carnot Efficiency and Solar Cells? The mathematics of population control.

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Dne 26/07/2015 v 20:05 Daniel S. Riley napsal(a):
> Poutnik <poutnik4nntp@gmail.com> writes:
>> Dne 26/07/2015 v 18:25 Grokman Grokman napsal(a):
>>
>>> The Q being: Must solar cells obey Carnot efficiency?
>>
>> Solar cells are not thermal engines,
>> working between 2 temperature levels,
>> transforming part of thermal energy
>> to work or other energy form.
>>
>> Therefore no, they do not obey it.
> 
> Hot and cold reservoirs of electrons separated by the semiconductor band
> gap.  Cold reservoir is room temperature, hot reservoir is temp of
> photons from the sun with energy greater than the band gap.  It's a
> thermodynamic process, so the Carnot cycle limit is thought to apply.
> However, that's just an upper limit, and there are good reason to think
> that solar cells can't possibly approach their Carnot limit.
> 
Hm, yes, in this context. But, temp of photons is not defined,
it is rather temp of radiation density.

-- 
Poutnik ( the Czech word for a wanderer )

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Re: Carnot Efficiency and Solar Cells? The mathematics of population control. Poutnik <poutnik4nntp@gmail.com> - 2015-07-26 20:51 +0200

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