He's learned that clean fossil fuel energy won't happen with the flip of a switch. it will take decades to perfect. The newer coal-fired plants are already much, much cleaner than the old.
His battery adventure was a $100M failure at taxpayer expense.
68% of electric/hybrid car buyers don't buy a second time. They dump before the lead-acid batteries need replacing.
Solar panels are nasty to produce and dispose of.
He's learned that we need a balanced approach, and that as a lame duck (with multiple unexplained scandals to deal with), he doesn't have the clout or the cred to impose his will on the American people anymore.
I've always wondered how electric cars are more environmentally friendly than gasoline powered cars. Aren't electric cars charged from an electric grid powered by... POWER PLANTS?! LOL. And where do those power plants get their electric power?
And how about those heavy metals in their batteries. Aren't they hazardous waste when they are depleted of their charging capacity?
All hybrids have both lead-acid and either nickel-metal hydride, or (in newer Prius) lithium-ion batteries. Toyota readily admits that the range issue in electric mode is the big gripe with consumers. The Nissan Leaf has the longest range (being totally electric) at 73 miles.
But they all still rely on some lead-acid batteries ( due to power demand issues) to run the lights, computers, etc. in electric mode.