Excessive Heat Stretch Will Stress Power Grid

Consumer conservation likely needed this weekend during excessive heat to avert power outages

FOLSOM – Starting today through Tuesday, California and the West are expecting extreme heat that is likely to strain the grid with increased energy demands, especially over the holiday weekend.

Temperatures are forecast to begin rising Wednesday, August 31, intensifying through the holiday weekend and extending to early next week. In many areas of the West, temperatures are forecasted to hit triple digits and break records.

In what’s likely to be the most extensive heat wave in the West so far this year, temperatures in Northern California are expected to be 10-20 degrees warmer than normal through Tuesday, Sept. 6. In Southern California, temperatures are expected to be 10-18 degrees warmer than normal.

The ISO is taking measures to bring all available resources online. Restricted Maintenance Operations (RMO) have been issued for Wednesday, Aug. 31, through Tuesday, Sept. 6 from noon to 10 p.m. each day, due to high loads and temperatures across the state. During the RMO, market participants are ordered to avoid scheduled maintenance to ensure all available generation and transmission lines are in service.

The peak load for electricity is currently projected to exceed 48,000 megawatts (MW) on Monday, the highest of the year.

If weather or grid conditions worsen, the ISO may issue a series of emergency notifications to access additional resources and prepare market participants and the public for potential energy shortages and the need to conserve.

The power grid operator expects to call on Californians for voluntary energy conservation via Flex alerts over the long weekend.

During a Flex Alert, consumers are urged to reduce energy use from 4-9 p.m. when the system is most stressed because demand for electricity remains high and there is less solar energy available. The top three conservation actions are to set thermostats to 78 degrees or higher, avoid using large appliances and charging electric vehicles, and turn off unnecessary lights. Lowering electricity use during that time will ease strain on the system, and prevent more drastic measures, including rotating power outages.

Learn more about conserving energy or sign up for text notifications by clicking here.

The ISO continues to closely monitor conditions and will provide updates as necessary.