how do i make a thermoelectric generator?
The only method I know with which you can make electricity out of heat (directly, not via a turbine like power stations do) is an electronic component called a thermocouple. Because one thermocouple gives off too tittle energy to do anything useful with it, you will require an array of several. Such array exists on the market, see http://www.hi-z.com/websit03.htm
And because there are not many practical applications where you can use a small amount of electricity near a heat source, the only “home-use” of this technology I have seen is a fan which you put on your oven / stove, to blow the warm air further to the centre of your room. Example:http://www.fluesystems.com/sundries/info…
You can’t really compare this with solar cells, because the energy sources are entirely different between those two.
The most noticeable difference is that one thermocouple produces a tiny amount of voltage at a reasonable current. Whereas photo cells produce a reasonable voltage at a “soft” current (higher internal resistance)..