I'm sick of people who make your completely bad faith argument, pretending storage doesn't exist or can't scale.
If it does, please prove me wrong and show me some sources showing that grid-scale storage exists, but I have yet to see it.
> Pumped storage is by far the largest-capacity form of grid energy storage available, and, as of 2020, accounted for around 95% of all active storage installations worldwide, with a total installed throughput capacity of over 181 GW and as of 2020 a total installed storage capacity of over 1.6 TWh.
https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...
See https://www.reuters.com/business/energy/china-leads-wave-cle... for some figures on curtailment.
Really, you're making another "it hasn't been done therefore it can't be done" clown argument.
Pumped (hydro) storage requires MASSIVE areas, all sorts of approvals, and often resettling people. This works fine in China where the government can just do whatever, but in places like California, we can't even approve new resevoirs for drinking/farming water, much less energy storage.
Can that change? Certainly. Is it likely to? Doubtful.
Realize that even in a fully nuclear powered world, huge amounts of batteries are needed. Replacing every ground vehicle in the US with a 70 kWh BEV would require enough batteries to store about 40 hours of the current average US grid power. So the scaling is needed regardless of the post-fossil energy source.
A longer term storage mode is also needed to deal with seasonal storage and covering rare Dunkelflauten as batteries are not suitable for that. Fortunately there are multiple ways that could be handled, so it's a question of which is best.