Temperature differences converted to electric...

[hartiberlin]

We need a "solar cell" that works efficiently at the frequency of waste heat.
Then we would need no cold pole, just stick this "heat solar cell" to the
heat source and you could extract some heat and convert it to elecricity...

This "heat solar cell" would just become colder as the surrounding  when current would be
drawn from it  and suck in the heat
automatically if electrical power would be drawn from it.

With it you could build a freezer (fridge) that generates electricity and does not need
electricity to run !

Hopefully some people in the microchip departments are already working on
such a "heat diode".

You would only need to put many million diodes with the right
microstructures in parrallel onto a wafer and make sure the
diodes are efficient at the thermal noise level.

[pese]

You can also USE .
Peltier elements !!
Some type that you can buy to produce heat or frigid.

THEY WILL PRODUCE ELECTRICITY IF you hold both side to differnt temperaures.

(Heat up with Solar  in parabol or fresnell , and cool down the antipod of peltier..)

PESE

[Koen1]

What most of you seem to forget (except Stefan who actually says it in a way) is that thermoelectircal effect between two metals of different temperatures is well known, but also only usefull when there is actually quite a substantial temperature difference between the hot and the cold metal.
This can be tapped usefully when we actually have one hot metal (like an engine exhaust for example) and one cold one (which is cooled continually for example).
But that also implies we already have a clear seperation of hot and cold.

In normal environmental temperature, there is no such seperation (most of the time).
If there is no clear distinction between a hot and a cold area, normal thermoelectrical elements will not work.

What we want is an electronic component that will actually ABSORB heat energy and turn it into electrical output.
Note this is different from using the kinetic energy difference between the hot and cold metal to obtain an electron flow.
Ideally we would not even have a hot and a cold metal between which the electrons must flow.
So like Stefan states, it seems what we want is more like a solar cell that runs off photons in the infrared/heat range, which has electrons flow because of direct excitation due to the heat energy and the n-p effect that is so crucial to the operation of solar cells.

another possibly interesting option is this: the Zaev-capacitor array. (http://jnaudin.free.fr/html/nzaevncp.htm)
In short, it is a ninlinear ferroelectric capacitor array which appears to convert ambient/environmental temperature directly into electricity.
During its function, the temperature of the air directly around the array drops, and the electrical output is at 135% of the input.
I haven't seen any replications of this array at all, anywhere, but the documentation provided by mr. Naudin seems to be quite solid.

oh and @mikey: though it is indeed very interesting to keep an eye on that thermoelectric energy chip that Eneco has developed and patented, I think we must keep in mind that Eneco is an energy company and that in general energy companies are not at all anxious about providing the populace with free or even cheap energy. The fact that they have patented it probably means it will never be marketed at affordable prices. After all, killing your own business is stupid. Much like the hydrogen technology and the biofuels, I fear it will be presented as a possible solution to the energy crisis, but in actuality the energy companies are gearing up to make as much money as possible on what should have become a cheap and sustainable solution...

[FreeEnergy]

question:  will this tech still work below zero temperatures? i.e -02 and -16 will give you electrical current. as long as you have temperature differences?

[FreeEnergy]

http://availabletechnologies.pnl.gov/technology.asp?id=85

http://www.geocities.com/capecanaveral/lab/5185/weird2.html