Homemade Thermopile

There are two major problems with thermopiles as tool to generate
electricity. Very low efficiency and high initial cost. It appears
that the only way to attack efficiency is to utilize more exotic (read
expensive) materials.

What I was wondering is could a "homemade" thermopile be constructed
using very cheap or recycled materials (nails, aluminum cans, aluminum
foil, metal scrap, etc.). If you consider sweat equity to be free you
might be able to produce a viable installation.

If possible, it would be best to utilize a natural occurring
temperature differential such as air to ground, air to water, or dry
bulb to wet bulb. I recognize that these are relatively small delta
T's, but they are completely free and universally available.

My questions are as follows:

Which, if any, commonly available materials would be best for such a
device?

What design parameters should be considered?
For example:
Do the cross-sectional area, distance between or shapes of the
junctions effect the output?
.

Relevant Pages

  • Re: Homemade Thermopile
    ... Very low efficiency and high initial cost. ... using very cheap or recycled materials (nails, aluminum cans, aluminum ... it would be best to utilize a natural occurring ... bulb to wet bulb. ...
    (sci.electronics.design)
  • Re: Homemade Thermopile
    ... Very low efficiency and high initial cost. ... using very cheap or recycled materials (nails, aluminum cans, aluminum ... it would be best to utilize a natural occurring ... bulb to wet bulb. ...
    (sci.electronics.design)
  • Re: Homemade Thermopile
    ... Very low efficiency and high initial cost. ... using very cheap or recycled materials (nails, aluminum cans, aluminum ... it would be best to utilize a natural occurring ... bulb to wet bulb. ...
    (sci.electronics.design)
  • Re: Homemade Thermopile
    ... Very low efficiency and high initial cost. ... using very cheap or recycled materials (nails, aluminum cans, aluminum ... it would be best to utilize a natural occurring ... Anything useful needs Watts, a few hundred ...
    (sci.electronics.design)