Energy only solves one issue. We still have production pollution, waste disposal, and as the Latinist mentioned, cost. I'd be shocked if profit-motivated companies didn't try to recoup the costs of construction as quickly as possible by charging a "clean energy" premium. Plus there's the big economic issue from re-employing coal miners and the coal industry, and we absolutely need to be cleaning up the old mines too.
If I managed free energy tomorrow it would just be one small win and a whole series of new problems. Best not to be deceived by the siren song of progress.