California power grid on alert against blackouts as heat wave looms for holiday weekend

The manager of California’s electricity grid issued an alert Wednesday for Labor Day weekend as it tries to avoid more rolling blackouts during an expected major heat wave.

With temperatures in the Sacramento Valley predicted to peak this weekend at 107 degrees, the California Independent System Operator issued a “restricted maintenance operations” notice. That’s an order directing power generators to defer any planned shutdowns for routine maintenance.

The order takes effect 6 a.m. Saturday and ends Sunday at 10 p.m. The region is bracing for four straight days of 100-degree weather, with the temperature expected to peak sometime Sunday.

California was hit with two nights of rolling blackouts in mid-August as temperatures soared well past 100 degrees, the first rotating outages since the 2001 energy crisis. However, the demand for electricity fell short of the all-time high, recorded during a 2006 heat wave, and Gov. Gavin Newsom has demanded an investigation into what went wrong.

ISO officials have said the blackouts became necessary in part because the state’s solar energy supply naturally dissipates as the sun goes down — triggering criticisms that California has moved too quickly to mothball fossil fuel plants in favor of renewable energy. The state relies on renewables such as solar and wind for nearly one-third of its electricity.

Newsom, however, has insisted the state won’t retreat from its green-energy goals — state law says the power grid must be 100% renewable by 2045 — while acknowledging California must do a better job of managing the transition away from fossil fuels.

On Tuesday, state regulators hit the pause button on the move to renewable energy. The State Water Resources Control Board allowed a group of aging gas-fired plants, scheduled to be closed in December to reduce air and water pollution, to continue operating for up to three more years in the name of ensuring grid reliability.