The only question is how to deal with intermittency of renewables. For which we have tons of options, with nuclear being a poor contender, IMHO. There are certainly some models of zero carbon energy grids that say nuclear is the cheapest way to achieve zero carbon, but I think those models have not adequately accounted for several key observations about the world, namely: 1) how storage technologies are getting cheaper far faster than anyone anticipated, by an order of magnitude, 2) how we will build a lot of hydrogen infrastructure anyway to decarbonize industrial processes that we can't electrify, and 3) how nuclear is getting more expensive every year because it relies on industrial techniques that have been optimized in the past, and where we are now losing skills. Even if we correct 3), I don't think it could outweigh 1 & 2.
That's not to say that nobody should invest in nuclear, just that nobody should bother with gen 3 or 4 designs, as they are already obsolete. Look to the tiny startups, and forget about the giant conglomerates of yesteryear like EDF, Toshiba/Westinghouse, and Hitachi.
And if we don’t quite solve it? Then what? This is why Bill Gates is on the board of a nuclear startup. Everyone wants renewables. But not investing in other forms of carbon free energy is simply gambling because a carbon free future must happen.
It's already solved. The only question is how expensive it would be. But nuclear's best case is already pretty expensive.
I’ve said this before. It’s not one or the other. The fallout of climate change is potentially so catastrophic, you need to spend the money on nuclear anyway. You have to double down just in case renewables don’t pan out 100% the way we hope. You want to spend the money to maximise the chances of a working solution.
Think of it like COVID vaccine trials. We’re spending money on multiple vaccine candidates in parallel.