They very likely can, but it would require a massive program of nuclear power plant building. This is unacceptable to environmentalists, who prefer to pretend that people will voluntarily reduce their quality of life.
It’s not just energy production and consumption that is the problem. Resource extraction, pollution, toxification of the environment are all contributing to the creation of a planet that sucks to live in.
Cheap energy goes a long way toward solving those problems. Many "rare" materials are only rare because they're energy intensive to extract, or they might not be needed at all (e.g. rare earth metals in motors and batteries) if we can afford to sacrifice energy efficiency in products. If we can irrigate all the deserts with desalinated sea water then there's less need for intensive agriculture. Pollution control technologies need energy to run and build, so cheaper energy means there's less opposition to using them.
The classic hyperboloid cooling tower works by evaporation, and the latent heat of vaporization of water is high, so a few degrees difference in the temperature of the make-up water isn't going to matter. It only matters with the more environmentally harmful once-through cooling, where the waste heat is dumped directly into the sea.