Flex Alert
What Is a Flex Alert?
A Flex Alert is a voluntary call to conserve electricity during times when California’s power grid is under stress and electricity demand is expected to be especially high.
Flex Alerts are most common during extreme heat events, particularly in the late afternoon and evening hours when energy use remains high and solar energy production declines.
When Californians reduce or shift their electricity use during a Flex Alert, it helps maintain grid reliability and can reduce the likelihood of more serious emergency measures, including rotating power outages.
What should you do when a Flex Alert is issued?
- Before 4 p.m.:
- Pre-cool your home for the evening by running your air conditioning during the day, when more clean energy is available.
- Enjoy the sun in the morning and adjust window coverings (shade, blinds, or drapes) in the afternoon to block sunlight and keep your home cool.
- Do chores that use large amounts of energy, like laundry or dishes.
- Wait to use major appliances until after 9 p.m.
- Raise your thermostat to 78 degrees and use fans if needed to stay cool.
The CPUC’s Role
The CPUC created the Flex Alert program as part of its responsibility to ensure that the state’s investor-owned utilities reliably serve their customers.
While CAISO issues Flex Alerts, the CPUC maintains oversight of the program and the public education and outreach efforts related to Flex Alerts and grid reliability.
The CPUC also helps advance demand response and load reduction programs that encourage customers to shift electricity use away from periods of peak demand.
Who Issues Flex Alerts?
Flex Alerts are issued by the California Independent System Operator (CAISO), the nonprofit organization responsible for managing the flow of electricity across most of California’s high-voltage power grid. CAISO monitors electricity supply and demand statewide and issues Flex Alerts when grid conditions indicate a potential supply shortage or heightened reliability risk.
Why Flex Alerts Matter
California’s electric grid is evolving as the state adds more renewable energy resources and electrifies transportation, buildings, and industry. During periods of extreme heat, wildfires, transmission disruptions, or unexpected power plant outages, voluntary conservation can make a meaningful difference.
Even small reductions in electricity use across millions of homes and businesses can help stabilize the grid and protect public safety during periods of high demand.
Stay Informed
Sign up to receive Flex Alert notifications and learn more about energy-saving actions during grid emergencies.