Stored hydro & nuclear solve entirely different demands. Nuclear's core strength is providing a strong, reliable, but relatively constant base-line. Wind/Sola

Stored hydro & nuclear solve entirely different demands. Nuclear's core strength is providing a strong, reliable, but relatively constant base-line. Wind/Solar can supplement (or even replace it) depending on costs and geographies, but their generation can be very spiky, and you don't get to pick the spikes (or troughs). Stored-hydro rounds off the trifecta by providing spikes on-demand, but also by absorbing over-production from other sources. Nuclear looks wonderful in a "spherical cow" calculation, but the reality is that nuclear strongly prefers a constant production, but demand is never constant. Under-production is obviously undesirable, but over-production is no easier to deal with. So it's not really about which is better - it's balancing the weak points in each system against the strengths of the others.