Flex Alert issued for today, calling for statewide conservation

August 17, 2020


California-ISO

Reducing energy use could avert rolling power outages during heat wave

FOLSOM, Calif. – In an effort to prevent or limit power outages during this heat wave, the California Independent System Operator (ISO) issued a statewide Flex Alert, a call for voluntary electricity conservation, for today and extending through Wednesday. The Flex Alerts are in effect from 3 p.m. to 10 p.m. each day.

California's record-breaking persistent heat wave has put extraordinary strain on the ISO electric system, as air conditioners are working harder and longer to keep spaces cool during the high temperatures. Because of high heat and limited energy supplies, rotating power outages are likely over the next two days.

Consumers can take stress off the grid by lowering energy use during the most critical time of the day, 3 p.m. to 10 p.m., when temperatures remain high, and the sun is setting, removing thousands of megawatts of solar power from the system.

Conservation efforts during these times can prevent more dire measures, such as rotating power outages, or generator equipment failures that can lead to more serious unplanned losses of power.

The ISO recognizes that reducing energy use during the hot time of the day is a hardship, especially for those working from home or with children schooling at home. However, if a large number of consumers do their part in small ways, conservation can make a difference.

Between 3 p.m. and 10 p.m., the ISO is urging consumers to:

  • Set air conditioning thermostats to 78 degrees, if health permits.
  • Defer use of major appliances.
  • Turn off unnecessary lights.
  • Unplug unused electrical devices.
  • Close blinds and drapes.
  • Use fans when possible.
  • Limit time the refrigerator door is open.

Consumers can also take steps to prepare for the Flex Alert by doing the following before 3 p.m.:

  • "Pre-cool" their homes, or lower air conditioning thermostats.
  • Charge electric vehicles.
  • Charge mobile devices and laptops.
  • Run dishwashers, washing machines and other major appliances.
  • Set pool pumps to run in the morning or during the night.

For information on Flex Alerts, and to get more electricity conservation tips, visit the ISO's Flex Alert website.

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A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are
subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions
and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.