We can do the bulk of it, i.e. more than 50%, by geographic and modal aggregation fairly easily. Doing all of it from renewables is still an unsolved problem that would require better energy storage.
Not necessarily enough wind to be useful. If you look at graphs of wind turbine output across entire large power grids, you see 4:1 variations in a day over the PJM and CAISO regions.
That's irrelevant to this blackout, anyway. This blackout occurred during a period when supply far exceeded demand.
