Statewide flex alert issued for Sunday as heat wave intensifies
FOLSOM -- For the fifth day in a row, the California Independent System Operator has issued a statewide Flex Alert beginning at 4 p.m. Sunday.
The alert comes as the state moves into the most intense heat of the summer, and the ISO prepares for challenging grid conditions over the next several days.
Under a Flex Alert, consumers are urged to set thermostats to 78 degrees or higher, avoid using major appliances and turn off all unnecessary lights between 4 p.m. and 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, according to the ISO.
Daytime high temperatures are forecast at 10 to 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. Sunday, Monday, and Tuesday in particular are shaping up to be the most difficult of this heat wave, forecasters say.
Tuesday's peak demand is forecast to be 50,087 megawatts, just shy of the all-time record of 50,270 MW set in 2006.
Grid operators are closely monitoring three wildfires – including the Mill Fire in Siskiyou County -- 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 as 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, according to the ISO.
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.
Under the Flex Alert, consumers are also encouraged to pre-cool their homes and use major appliances before the start of Flex Alert at 4 p.m. For information on Flex Alerts, and to find more electricity conservation tips, visit FlexAlert.org.
Before 4 p.m.:
- Pre-cool home by setting the thermostat to as low as 72 degrees
- Use major appliances, including washer and dryer, dishwasher, and oven and stove for pre-cooking and preparing meals
- Charge electric vehicles
- Adjust blinds and drapes to cover windows From 4 p.m. to 9 p.m.:
- Set thermostat to 78 degrees or higher, if health permits
- Avoid using major appliances and charging electric vehicles
- Turn off all unnecessary lights About Flex Alerts 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.
