Room temperature superconductors could solve a lot of issues for the whole planet. Run lines to all countries from a few solar farms spread around the globe and you have constant power delivered everywhere with no losses, at all times. Sun shines somewhere at any point, and the surface we'd need to ensure most if not all our energy needs is quite irrelevant, all things considered. Have them float in the ocean and installed in some remote places on land where the case, really no issue.

Just a few tech advances can massively change things. The real problems are of different nature, who benefits from it? The entities who sell energy to the whole world won't just give it up for the benefit of humankind. It doesn't really work like that in the real world. Hell, there's a whole history of sabotaging energy sources, just so some countries depend on these entities for energy.

As long as humans are in control, there will be a lot of nonsense like this. It's not a problem that we cannot really solve it, it's rather...are we really allowed to solve it?