I bought a peltier heat pump from
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I've been trying to use old computer heat sinks and the exhaust manifold to generate electricity. So far I've been fairly unsuccessful. I have gotten some amps but not much, the problem is that the pump is flat and the exhaust is round. 2 things would help, a pipe shaped pump and higher Seebeck coefficient which can be achieved by using bismuth telluride instead of copper and aluminum.