[elihu]

Power generation creates a lot of heat too. Coal, natural gas, and nuclear power plants usually all operate by boiling and recondensing water, and as a consequence they have cold water as an input and warm/hot water as an output. That's a problem for rivers. France recently had to reduce output on their nuclear reactors because running them full power would make the rivers unacceptably warm.

I suppose it's less of an issue if your power plant uses sea water as coolant.