What you are pointing out has nothing to do with bitcoin because bitcoin or more precisely bitcoin miners are simply consumers of the electricity not the producers of it. How electricity is produced (renewable energies, less polluting methods, ...) is up to the electric companies.
What is needed to be addressed is not energy consumption but how much the mines spend on energy consumption. If they get to a more renewable source power plant or have their own power plant then they can dramatically reduce the consumption expenditure. The only problem with it is that there isn't a lot of money in mining these days so there is little to no big investors willing to put in their money. I know that there are other ways to reduce bitcoin's power consumption but I am still skeptic about it because it may interfere with its internal process which could disrupt things in the long term.
