Wind energy is generally not reliable in the PNW during cold waves

I suppose that the counterargument to this article would be that renewable energy sources should be buffered by utility-scale batteries. That raises an interesting question: how much battery capacity would one need to replace coal/gas-powered peak load generators? I suppose that the answer would vary a lot from region to region.

Also interesting is the fact that nuclear power output seems to have been totally unaffected by the cold weather. On the other hand, I do recall anecdotes about French nukes suffering from hot weather.