A minor caveat: some regions have large hydroelectric generation, which doubles as a great energy storage site. Countries seem to be able to manage a roughly 1:1 ratio between intermittent sources and hydroelectric generation. Sweden is managing to decarbonize it's grid with ~1/3rd each of nuclear, intermittent sources, and hydroelectric.

But for much of the world what doesn't have this option, nuclear remains the most viable energy source.