Adelaide, Australia used to have constant rolling blackouts, including a state wide blackout once. After that, Tesla (pre insanity era) built a grid battery storage system which essentially fixed the problem. I'm sure there were other improvements to the grid at the same time. But these days the grid is incredibly stable while also being majority solar and wind powered. The battery is able to buy and sell power daily and profit on the difference between high and low demand times. And if there's an equipment fault somewhere, it can respond fast enough to cover the time between a generator going offline, and the backup ones starting up.