And what, pray tell, would we be using for storage instead? Surely you're not going to suggest some untested and unproven storage mechanism like hydrogen storage, ammonia, thermal batteries, etc. Those technologies have never been built at anything remotely close to grid-scale, and thus we have no idea what they'd actually cost when we attempt to build them at grid scale.
Batteries and hyrodelectric storage are the only energy storage mechanisms for which we have any meaningful cost history.
Yes I'm well aware of the numerous alternatives you repeatedly insist are incredibly cheap and scalable, despite the fact that no such systems have been deployed.
Yes, I realise that. That's why I said "I don't know" and "for comparison".
My point was that GWh-scale thermal battery proposals would be competing with already existing (and possibly cheaper) chemical batteries, and that energy storage on this scale is not unheard of.
The point is that current energy storage facilities are too small for fully renewable grid (or arguably even 60% renewable grid).
Even as a nuclear supporter I would welcome more renewables if we had cheap scalable storage, which no one has it seems. (at least no one pointed out such project in the entire thread)
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.
The only deployed thermal storage systems are in solar thermal arrays. Those have costs that aren't not competitive with nuclear, and they're still subject to seasonal output variability due to weather and Earth's inclination.
District heating systems distribute heat, usually scavenged from a power plant. They don't store heat really - they do in a pedantic sense in that heat is "stored" in the distribution pipelines, but not in the sense of a battery. And they don't transfer heat at gradients large enough to generate electricity effectively.