Martin McCormick wrote:

>	I am deliberately asking what may sound like one of the
>dumbest questions we've had on here in recent history, but this is
>more along the lines of "What is the catch?"
>
>	Thermocouples produce electric currents at any temperature
>above absolute 0.  Voltages in series add,
>so one should be able to place millions of thermocouples in series
>and generate some power from the ambient temperature.
>
>	Even the most rabid spammers haven't tried to sell something
>like that so what really does happen if you hook a billion
>thermocouples in series?  It obviously doesn't work since the
>technology to make the world's largest series string of thermocouples
>has existed for as long as we have been bonding metal together which
>is a very long time.
>
>	Can you imagine how terrible the voltage regulation would be
>in such a setup?  I also suspect that as soon as one drew any current
>from the stack, it would act like a heat pump and cool down just
>enough to stop working.
>
>	The amateur radio magazine "QST" once had an article
>describing how to use a Peltier cooling element to generate enough
>power to drive a very small transmitter.  It actually did work, but
>one had to have a high temperature differential between the two sides
>of the Peltier device such as almost boiling water on one side and ice
>water on the other and the two sides began rapidly moving toward
>temperature equilibrium as soon as the current started to flow.
>
>Martin McCormick WB5AGZ  Stillwater, OK 
>OSU Information Technology Division Network Operations Group
>  
>
Hi there Martin
(I'm a Martin too)
Thermo-electricity has been used to produce electricity since before 
mechanical generators, they were one of the first methods of producing 
electricity for the electroplating industry. I can't seem to remember 
the name of a website that I saw, but it had many examples of what I 
think are called thermo-piles. They had many themocouples (up to 
hundreds) and usually sat over a gas flame with the hot ends pointing in 
and the cold ends pointing out in a star shape.

--
Martin K
http://wwia.org/sgroup/biofuel/
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