California Hits 100% Renewables for (Parts of) 100 Days Straight

California recently hit a new renewable energy milestone: 100 days of 100% renewable energy powering the state’s electricity grid, run by the California Independent System Operator (CAISO), for at least part of the day.

Mark Jacobson, director of the Atmosphere/Energy program at Stanford University, posted the milestone on LinkedIn on July 28, with a link to his own data tracking California’s WWS usage.

“Reaching 100 days of 100% clean renewable wind, solar, geothermal, and hydroelectricity (wind-water-solar) demonstrates real progress toward powering California without dirty fossil fuels,” Jacobson said in a statement released by Environment California. 

“To solve the climate crisis and cut air pollution, we must resolve quickly to deploy currently available technologies such as solar panels, wind turbines, battery-electric vehicles, electric heat pumps, electric induction cooktops, and batteries to store electricity.”

Others involved in the push for clean energy chimed in with their own celebratory posts.

“California’s remarkable renewable energy progress shows the world that we can tap into abundant clean energy sources such as the sun and the wind to sustainably power our lives,” Steven King, Environment California’s clean energy advocate, said in a release. “Days where we reach 100% renewable energy are becoming strikingly common, and this latest milestone provides hope that one day we can meet 100% of our energy needs from renewable sources every day of the year.”

In 2017, California was the first U.S. state to set itself on a path to 100% clean energy with the passage of Senate Bill 100, which commits the state to supplying all its customers with electricity produced from zero-carbon, renewable energy by 2045. Since then, notes Power Technology, “California, Hawai’i, Washington, and New Mexico are working towards fulfilling this promise by 2045, while Connecticut, New York, Minnesota, Oregon, and Michigan are aiming for 2040.”

More recently, on August 14, Jacobson posted another record for renewables: two consecutive months when wind energy outperformed coal in the United States, in April and May this year.

“First time ever, U.S. wind output exceeds coal’s for two months in a row,” Jacobson said in his post. “Plus, wind output up 3,530%; coal output down 87.6% from 2004-2024.”

Jacobson cited this article from the Daily Energy Insider, presenting data from the U.S. Energy Information Administration.

“In March, wind installations in the United States produced 45.9 gigawatt hours (GWh) of electricity, compared with 38.4 GWh from coal-fired power plants,” the Daily Energy Insider writes. “In April 2024, coal-fired generation fell to 37.2 GWh, while wind generation increased to a record 47.7 GWh.”

Looking back 20 years, the Insider cites comparable data that “shows how wind generation has grown. In March of 2004, coal-fired generation produced 154.3 GWh of electricity, while wind produced 1.3 GWh.”