A B S T R A C T

Critics of a global transition to clean, renewable electricity argue no wind- or solar-dominated grids exist and solar and wind’s variabilities cause blackouts. This paper uses data from the world’s 5th-largest economy to show no blackouts occurred when wind-water-solar electricity supply exceeded 100 % of demand on California’s main grid for a record 98 of 116 days from late winter to early summer, 2024, for an average (maximum) of 4.84 (10.1) hours/day. Compared with the same period in 2023, solar, wind, and battery outputs in 2024 increased 31 % 8 %, and 105 %, respectively, dropping fossil gas use by an estimated 40 %. Batteries, which shifted excess solar to night, supplied up to ~12 % of nighttime demand. Wind-water-solar is not the cause of high California electricity prices; to the contrary, most all states with higher shares of their demand met by wind-water-solar experience lower electricity prices. Thus, data support models: a reliable wind-water-solar-dominated large grid appears feasible.

A new study published in the journal Renewable Energy uses data from the state of California to demonstrate that no blackouts occurred when wind-water-solar electricity supply exceeded 100% of demand on the state’s main grid for a record 98 of 116 days from late winter to early summer 2024 for an average (maximum) of 4.84 (10.1) hours per day.

“Despite the rapid growth and high penetration of [wind-water-solar] WWS, the spot price of electricity during the period dropped by more than 50% compared with the same period in the previous year, and no blackouts occurred, giving confidence that the addition of more solar, wind, and batteries should not be a cause for concern.”

This paper shows that the main grid in the world’s fifth-largest economy was able to provide more than 100% of the electricity that it used from only four clean renewable sources: solar, wind, hydroelectric, and geothermal, for anywhere from five minutes to over 10 hours per day for 98 out of 116 days during late winter, all of spring, and early summer, as well as for 132 days during the entire year of 2024, without its grid failing.

Instead, in California, the spot price of electricity dropped by over 50% during the period of interest between 2023 and 2024, indicating it was easier to match demand with supply with the increase in renewables and batteries in 2024.

Top comment by G Reg | 1 day ago

The authors don’t mention anything about the significant carbon-free contribution of California’s sole nuclear plant.

Also, they don’t really make it clear that fossil fuels never drop to zero for California….only that WWS exceed demand (which means excess goes to battery for evening use).

It also doesn’t mention anything about the terrible change that killed off net metering, largely curtailing rooftop solar. We could have done even better.