Though there are no signs that residential utility customers need to reduce their energy use, a lingering heat wave covering much of California has prompted the state’s grid operator to send an alert to power companies.
The California Independent System Operator has issued a Restricted Maintenance Operations notification to utilities (such as San Diego Gas & Electric) and electricity transmission operators, instructing them to avoid performing routine maintenance through 11:59 p.m. Thursday. When high demand on the electric grid is anticipated, such notifications are sent to make sure all generators and transmission lines are available.
In addition, a Transmission Emergency for Northern California that has been in place since July 3 will remain in effect through Wednesday night. California ISO officials are keeping on eye on whether wildfires in the area could affect transmission facilities in the region.
“The hot weather is persisting, but the grid remains stable,” the ISO said on a post Sunday on X, formerly known as Twitter. “We are not expecting any energy supply shortfalls … as we continue to monitor the hot weather and wildfire activity.”
Northern California has borne the brunt of the heat wave that has lasted more than a week.
Sacramento hit a high of 113 on Saturday, July 6, setting a city record for that date. Hot weather forces homeowners and businesses to crank up their air conditioners, increasing demand on the electric grid.
Wildfires also put power lines and electricity infrastructure at risk. The Thompson Fire that started on July 2 near the town of Oroville in Butte County destroyed 13 homes and led to the evacuation of 13,000 residents. As of Sunday, Cal Fire officials said the fire is 86 percent contained and said it charred nearly 3,800 acres.
Though not serious as other areas of the state, parts of San Diego County have also sweltered in the heat.
The National Weather Service on Monday predicted high temperatures of 94 degrees in Escondido and Julian, 99 degrees in Campo and 121 degrees in Borrego Springs and Ocotillo Wells.
No wildfires have been reported in the San Diego area, although firefighters — who have battled a series of recent brushfires — are on alert.
California ISO officials expect to have enough energy supply to cover demand. The system is projected to have about 55,000 megawatts available on Monday, more than enough to meet the expected peak demand of just over 43,000 megawatts.
Whenever demand on the grid threatens to outpace the available megawatts needed to keep the power system running smoothly, the ISO issues a number of different measures. One of the tools is a Flex Alert, in which the grid operator asks utility customers to voluntarily reduce consumption in the late afternoon and early evening hours, when the power system is under the most strain.
The ISO has not indicated any Flex Alerts are in the offing during the current heat wave, but said, “Consumers can always help maintain reliability by conserving energy when possible from 4-9 p.m. on hot days.”
No Flex Alerts were issued last year but in 2022, a “heat dome” that blanketed California and neighboring states in late August through early September prompted the system operator to issue a record 10 consecutive days of Flex Alerts.
For all of 2022, 11 Flex Alerts were announced.
