@chuculate

This is already well quantified and modeled, and I wouldn't be such optimistic:

"Even in the cases in which 80% of electricity is supplied by intermittent renewables on the annual average, there are still times when wind and solar is providing very little power, and if blackouts are to be avoided, the gap-filling dispatchable electricity service must be sized nearly as large as the entire electricity system."

https://kencaldeira.wordpress.com/2018/03/01/geophysical-constraints-on-the-reliability-of-solar-and-wind-power-in-the-united-states/