There's an interesting breakthrough in drilling technology that could enable us to drill way deeper than before at a fraction of the cost. Using that method existing coal plants could be converted into steam power plants. Basically laser drilling. It's already finished proof of concept and they're moving to large scale testing.
Also some possible breakthroughs in battery technology but the future will depend on if existing factory lines can adapt to it or if new ones are required. Interestingly lithium battery technology was invented a while before it was adopted. Japanese battery manufacturers simply didn't see a reason to spend money making new factory lines since they already had majority market share, so now they aren't known for making the best batteries any more.