Technically, storage is a solved problem. It's not even hard, and y'all keep saying it's impossible. The unsolved problem is cost. And it's a simple formula... how much grid storage is needed to account for variations? And what does that storage cost? The moment the combined wind/solar + storage cost drops below the cost of coal/nuclear, it wins.

And intermittency for wind is completely overblown (no pun intended). Tower-height winds are much steadier than surface-height winds, due to lack of surface-related turbulence. And we have a couple of decades of measurement of large wind installations, so the expected variation isn't exactly a surprise unknown.