LOS ANGELES (AP) — A heat wave sent Californians to their air conditioners Friday and drove power demand to its highest peak of the year as the southern region sweltered under 100-degree temperatures.

Statewide electrical demand peaked Monday afternoon at 45,090 megawatts, beating a record for the year that was set on July 30, said Steven Greenlee, spokesman for the California Independent System Operator, which runs the state’s power grid.