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2answers
1k views

Increase thermal efficiency of combustion engine by using heat of coolant/exhaust?

I can't be the only one who's ever thought of this, but obviously it hasn't caught on: In terms of energy density, fossil fuels are the best thing around short of enriched uranium (and, flammability ...
1
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3answers
209 views

If humans were able to catch all sun energy reaching the earth for their use, will the climate change?

I guess that energy will be used up and, at the end, will contribute to heat the earth, so I see no big differences... please explain your point of view.