At this size (4GWe) it was no big deal, the hydro plants can cover easily. But at 50 or 100% renewables it's much more challenging because entire regions can go

At this size (4GWe) it was no big deal, the hydro plants can cover easily. But at 50 or 100% renewables it's much more challenging because entire regions can go down unpredictably. The 1 GWe nukes go down for outages generally in a staggered way (though not always, for instance in a common-cause design concern)