Comment by probablypower

Batteries don't provide meaningful flexibility on a continental scale. They're useful in localised frequency control or microgrid flexibility.

An exercise to the reader, calculate the space and materials required to replace the average norwegian hydro reservoir with batteries.

Nuclear tech doesn't provide required ramp rates at a useful price. I do agree however that more nuclear helps.

The problem is dispatchability/flexibility, not storage. At a more complex level the issue is grid inertia and frequency response.