It is unlikely that they wont progress dramatically, but even in that extreme case there's no need or reason to wait.
One factor people don't consider is reliability of power. Since solar and wind are unreliable (example, German wind power saw -25% generation last year due to weather, and ended up increasing coal by as much as 40 to 50% to make up for it plus meet new demand) you end up needing to produce significantly more to have a guarantee of baseload.
For every bit of ultra-reliable, ultra-safe, tiny-footprint nuclear you build out, you need ~4X the amount of less reliable and giant foot print solar or wind.
Yes, wind and solar are limited in their available capacity by the weather. The trick to get reliable power generation nonetheless are wide range networks (mitigates weather influences), storage solutions and storable renewables like bio-gas.
For the gap, gas powered plans are the key. Even in the worst case, they are way more environment friendly than coal, only emit a fraction of the CO2 at the same output. But beyond that, they can be quickly switched in output, they are the ideal counterpart to wind and solar. That is the weakness of coal and especially nuclear power plants.
Also, one can afford a lot of overproduction capacity for the cost of a new nuclear power plant.
Two reactors out of 56 needed an inspection once in a while? Do you think a gas plant never stops for repairs?
Why do you resort to anecdata when we have statistics on reliability going back decades?
You have it totally backwards: the reliability of coal and especially nuclear to produce a constant output is the strength! That's called baseload generation, the ability to produce large amounts of power reliably, rain or shine, night or day, windy or still for a set low cost.
This is why nuclear is the best to pair with unreliable solar/wind technologies. Not only is nuclear DRAMATICALLY more friendly than literally burning oil like you suggest, it also provides a completely stable baseload for your industry. The idea that someone would suggest using oil over nuclear is insane. Are we trying to save the planet or not? There is nothing environmental about gas! It's a non-renewable resource that is likely already "post-peak" and will experience increasing scarcity and dramatic price increases over the next century.
Needing peaker power ontop of baseload, such as gas plants, is a different aspect of power generation. You wouldn't want to use gas as base, and you can't rely on solar/wind as base. As Germany in the real world evidenced: coal is the backstop for base there.
And when you consider how many batteries one needs for all the extra generation one is using because of their weird dislike of the greatest and greenest power generation technology there is, one should consider the ecological and environmental impact. Nuclear build outs are tiny and use a fuel whose energy density is several orders of magnitude above everything else. Solar takes up a huge amount of space and takes a lot of materials that are messy to mine for that nuclear doesn't. Consistent generation > battery storage every time.
A perfectly fine plant, Fessenheim, was shut down recently due to antinuke luddites.
I'm not convinced that's true. Lithium iron phosphate batteries are pretty good, and as far as I can tell they're expensive outside of China for artificial reasons. (Chinese manufacturers have a deal with the owners of the LFP patents something like: if you don't enforce your patents in China, we won't export our batteries outside of China. The last major patent expires in April I believe, so maybe the situation will change then.) If you could reliably buy LFP batteries in the U.S. for under $100 a kwh, I would expect that to change the economics of grid storage quite a bit. Maybe coal would still be cheaper, but coal has some pretty significant externalities.
It might be possible to do nuclear more cheaply than we've done it in the past, and if so that would be great, but so far it's fairly expensive and we still don't have a good political solution for the problem of what to do with the waste. I'm generally in favor of more nuclear being built, but renewables are a viable alternative if grid storage is cheap enough and/or our power grid is capable of moving power around over long distances efficiently. (There was a story a couple months ago[1] that Chile is planning to export solar power to China via an undersea cable. If they pull it off it would mean China wouldn't need to buffer 12 hours of energy to get through the night because they literally have solar installations on opposite sides of the Earth.)
Few appreciate the “brick wall” facing variability in green energy: if the battery depletes, power flow stops.
Batteries cost the same to cover whatever multiple of standard deviation prepared for. “Hundred year calm/clouds” need be prepared for - there’s no discount on installing that battery backup, very costly for a rare event (still often enough to need coverage).
When the batteries deplete, system halts until nature decides to provide enough again. FF reserves can tide over, nuclear will glow on; green varies by hour where outages can last weeks.
I run my office on solar every summer. Battery depletion is a very real, common, and costly issue.
Once you're preparing for events that rare, you have to first prepare for more common events, like failures in the power transmission infrastructure (the latest widespread one in my country, for instance, was only 11 years ago). And a lot of the preparation for these more common events (for instance, backup generators) would also help with these more rare events.
A nuclear power plant is $10,000/kW.
Back up the entire grid with turbines burning hydrogen or other renewable fuel and you're good, and it's still cheaper than using nuclear.