Having enormous synchronized grids helps a bit with that.

It’s highly unlikely to be abnormally cloudy/calm over the whole of Europe, for example, so Europe’s large grid (https://en.wikipedia.org/wiki/Continental_Europe_Synchronous...) can be used to move electricity from where there’s excess energy from solar or wind to where there’s a deficit.

That requires large capacity connections, though that aren’t everywhere yet.I understand electricity was restored in the south of France much more rapidly last week than in Spain and Portugal because it’s much better connected to the rest of Europe.