[unFou]

Have you made simulations or calculations to this effect? (or alternately, point me to the analysis of those who have). I'm not sure hand-waving it away as it'll wash out on average should be a valid response to something as critical to modern life as the power grid.

Some questions that might be interesting: What is the current downtime of electricity. What would be the desired goal for the new mixed / renewable grid? Given existing patterns of wind and solar generation, how much storage needs to be installed to reach this goal? How much would this storage be expected to cost at today's prices, and then with projected future savings from scaling (this could be used as a higher bound)?

The reason "running out" might be a valid concern is that the power grid is currently reasonably robust. Turbines are massive, with a great deal of inertia, meaning that even if something drastic were to happen, they can often cope with spikes in load long enough for extra production to ramp up. Wind and solar less so. Batteries presumably would be pretty great for ramping up, assuming we get enough of them on the grid. But then the economics needs to take into account the price of not just the renewables, but also generation.