It is my understanding that a car engine is inefficient in terms of fuel to actual kinetic energy output. I was wondering if it would be possible to harness all the heat by-product to charge the battery. I have no idea where one would get ahold of a thermopile capable of actually making a difference, but it seems logical to me. I think the output would be DC; would that mean it could be hooked up directly to the battery? If this is the case, it seems like a really simple method to improve efficiency.
What do you think? Does this seem plausible or is it not as simple as I am making it out to be?
Thanks for any input.