Solar is one of the largest sources of electricity in California’s grid, routinely producing 30–40% of midday power on sunny days.
In 2024, California installed much less residential solar vs previous years: SEIA reports residential installations fell ~45% compared to previous year, partly due to changes in net-billing policies.
On the storage front, S&P Global expects ~11.7 GW of battery storage projects in California to come online in 2025.
According to S&P Global, CAISO’s daily solar generation averaged 136.5 GWh/day in one quarter, the highest among U.S. regions.
According to SEIA, California has ~52,270 MW (52.27 GW) of cumulative solar capacity. This makes California the top U.S. state by solar capacity, followed by Texas with 43.6 GW.
In 2023, California generated ~68,816 GWh from solar (utility + small scale). That represented a ~9% increase in solar generation compared to 2022.
The main challenges include:
Reduction of excess solar power during midday. Even with more storage, a non-trivial portion of solar generation is being curtailed, which means there’s still some inefficiency in how excess solar is managed.
Need for more storage, transmission, and demand-shifting.
Debates over farmland use and land-intensive solar development.
Evolving rooftop-solar economics due to tariff changes.
In 2024, California’s solar energy output peaked at 19,600 MW on the grid.
Around 1,400 MW of new rooftop solar were reportedly installed in 2024, despite policy headwinds