I mean, nuclear might be expensive, time consuming to build, and difficult but at least we've been doing it for 70 years. It's not clear that projections of long term costs on things we haven't even done at scale are going to be realistic when we try them in the real world.

Even if it takes 20 years to build a nuke, that might still be sooner than "power to x" becomes a viable, affordable option for most of the world.

This is the weird thing about this argument: it so often rests simultaneously on an argument for practicality and/or cost effectiveness, but literally any criticism is met with a gish gallop of unproven technology. You can't have this both ways.

In the end, my central thesis here is just that if you think the be all and end all of this issue is cost effectiveness you are optimizing for the wrong goals and it leaves open a giant window for carbon emitting sources to justify their use when renewables don't work for various local reasons.

The thing to be black and white about is carbon emissions. "What energy mix works for place X right now if we try to eliminate carbon emissions asap" is not a decision that's gonna be made on an internet forum.

You're aware that current commercial nuclear power plants cannot power the world, right? They are thermal burner reactors. Supplying the entire world's current primary energy demand would require about 6000 1 GW(e) (which is 3 GW(th)) reactors. These would use up current uranium resource (not reserve) in about five years.

A nuke powered world will either require radically new sources of uranium (like sea water uranium extraction) or breeder reactors. Neither is available now, unlike cheap electrolyzers for making hydrogen (< $300/W in China).

Please point to me saying anything about "powering the world" with nukes. What a ridiculous strawman. This isn't Mortal Kombat: Energy Edition.

This is all about moving off fossil fuels because of induced climate change. That requires changing what powers the world. If nuclear is not going to power the world, then it's basically irrelevant, and the issues raised against renewables will not block their widespread adoption.

No one thing is going to power the whole world. Even "renewables" isn't one thing, and it can't and won't be deployed the same way in every climate or environment. It, as a blanket set of things, should be deployed everywhere however it can be. But there is no reason to exclude nuclear a priori as a blanket thing. And especially not in favor of waiting for promised improvements in storage or synthetic fuels that have not yet been proven.

Again, this is not a duel to the death. The only thing that should be dismissed out of hand is carbon emitting fuels.