How Clean Energy Kept California’s Lights On During A Historically Extreme Heat Wave


A two-week heat wave in California put the electric grid to an extreme test, but despite record demand the power stayed on, largely due to the fact that the state has gone all-in on clean energy technology like wind, solar, battery storage, and demand response. For more read: How Clean Energy Kept California’s Lights On During A Historically Extreme Heat Wave.

Key Takeaways:

  • Batteries played a critical role in keeping the grid running, and without them we would have experienced rolling blackouts. California has more than 3.2 GW of batteries supporting the grid, up from just 250 megawatts in 2020. These batteries typically provide four hours of energy, so that’s 150 times more energy from just two years ago. 
  • Customers also played a part, drastically reducing power usage after text alerts asked them to conserve power. This did help, but can’t be relied upon in every situation.
  • Renewable energy sources helped, too, but did need battery backup. Solar provided a consistent source of power during the day, but dropped off in the evening, when the demand increased. Wind did pick up in the evening. 
  • The state is racing to install more solar, wind, batteries, as well as transmission to connect all these new resources to the grid.

Path to 100% Perspective

It’s encouraging to hear that 10 states have already set decarbonization goals, but it isn’t enough. The Path to 100% will take support from everyone– from government and business leaders to private citizens. While the path isn’t the same everywhere, it includes some common steps, like increasing the use of renewables while incorporating storage and flexible power plants that can provide a source of energy backup when renewables like wind and solar are not enough. Without a plan to ensure firm, reliable power at all times, support of the energy transition could decrease.