FOLSOM, Calif. – As the state moves into the most intense heat of the summer, the California Independent System Operator (ISO) is preparing for challenging grid conditions over the next several days, and calling on Californians to lower electricity use during Flex Alerts.
A Flex Alert is in effect today from 4 to 9 p.m., when consumers are urged to set thermostats to 78 degrees or higher, avoid using major appliances, and turn off all unnecessary lights. Another Flex Alert has been issued for tomorrow, Sept. 4, also from 4 to 9 p.m.
Additional Flex Alerts will likely be called as heat will only intensify through Tuesday, with little relief from triple-digit temperatures seen over the next several days. Daytime high temperatures are forecast at 10-20 degrees above normal in much of the state through the Labor Day weekend and into next week, and record-breaking heat is projected in some parts of California.
Conditions are expected to be tight this evening, with a potential for supply shortfalls. Still, Sunday, Monday, and Tuesday in particular are shaping up to be the most difficult of this heat wave. Tuesday’s peak demand is forecast to be 50,087 megawatts (MW), just shy of the all-time record of 50,270 MW set in 2006. For more information, see the ISO’s Peak Load History report.
The peak load yesterday was 45,829 MW, and the forecast for today is about 45,000 MW.
Grid operators are closely monitoring three wildfires – Route Fire, Border 32 Fire, and the Mill Fire -- with varying threats to transmission lines. State fire officials have warned that more fires could break out in the coming days, adding to the risk of lost lines or generation.
Several generators have already been forced out of service, making supplies tighter.
Consumer and commercial demand response, including Flex Alerts, has been helping to ease strained conditions on the grid at critical hours so far this week, giving operators extra cushion in supplies.
Flex Alerts help alleviate stress on the grid in the late afternoon and evening when solar production rolls off the system, and demand remains high.
Consumers are also encouraged to pre-cool their homes and use major appliances before the start of Flex Alert at 4 p.m.
Reducing energy use during a Flex Alert can help stabilize the power grid during tight supply conditions and prevent further emergency measures, including rotating power outages.
For information on Flex Alerts, and to find more electricity conservation tips, visit FlexAlert.org.
Tips before a Flex Alert:
- Pre-cool home by setting the thermostat to as low as 72 degrees
- Use major appliances:
- Washer and dryer
- Dishwasher
- Oven and stove for pre-cooking and preparing meals
- Adjust blinds and drapes to cover windows
Tips during a Flex Alert from 4 p.m. to 9 p.m.:
- Set thermostat to 78 degrees or higher, if health permits
- Avoid using major appliances
- Turn off all unnecessary lights
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.
Follow developing grid conditions at the ISO’s News webpage, under the System Conditions Bulletin, or follow us on Twitter at @California_ISO.
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.
