How does this graph consider that 2024 isn’t over, yet, unlike the other years? Otherwise looks promising.

Edit: just saw this is only for April of each year. But similar question: can we extrapolate from April to say November or not?

You can't directly extrapolate from April to November. April is generally the optimal month in California for renewable generation (days are long enough, rainy season is drawing to a close, not too cold or hot, and summer fog from the oceans hasn't started), so the graph is definitely showing the best case. Nonetheless, with more battery installs, we can almost certainly bank the majority of power needs all year round in California.

There's a future issue looming: at some point, a lot of the natural gas peaker plants build for 2021 capacity will be idle almost all of the time. (Based on how often my local peaker plant seems to run, that may actually already be the case).

Keeping peaker plants around and having them ready year round for just a few days use is going to feel expensive; but decommissioning the plants too early has its own risks.

California has a capacity payment mechanism for this reason.

Love this graph, really demonstrates the power of low cost solar and increasingly lower cost batteries.