Stored electricity is much more expensive than nuclear electricity. To replace 1 GW of nuclear running at 92% CF with solar+storage, you need 3-4 GW of solar nameplate plus enough storage to cover nighttime AND multi-day cloudy periods AND seasonal winter deficit. The seasonal piece is what blows up the cost, you'd need weeks of storage, which at current Li-ion prices is economically absurd ($1000s/MWh delivered).