Salvador Espinosa sweeps in the kitchen of a Mary’s Pizza Shack restaurant during a Pacific Gas and Electric Co. power shutdown in Santa Rosa, Calif., Thursday, Oct. 10, 2019. More than 1.5 million people in Northern California were in the dark Thursday, most for a second day, after the state’s biggest utility shut off electricity to many areas to prevent its equipment from sparking wildfires as strong winds sweep through the region. (Christopher Chung/The Press Democrat via AP) (Associated Press)

SAN FRANCISCO — The lights were back on Friday for more than half of the 2 million Northern California residents who lost electricity after the Pacific Gas and Electric Co. utility switched it off to prevent its equipment from sparking wildfires during dry, windy weather.

But the threat of widespread outages loomed large in Southern California after the winds moved south to the Los Angeles area, where a wildfire fueled by strong Santa Ana winds prompted officials to order the evacuation of 100,000 people from their homes in foothills of the San Fernando Valley on the northern edge of Los Angeles County.

PG&E restored the power in Northern California after workers inspected power lines to make sure it was safe to do so. The winds had increased the possibility of transmission lines toppling to the ground and starting wildfires.

The utility said 426,000 Northern California businesses got their power back — but that 312,000 customers were still in the dark. About half of those who lost power in the San Francisco Bay Area had it again on Friday. The city itself was not subject to the preventive outages. Experts have said there are between two and three people for every electrical customer.

Some people in the largely rural Butte, Plumas and Yuba counties on Friday were in their third day without electricity. Butte County is where a fire started by PG&E equipment last year decimated the town of Paradise and killed 85 people.

To the south, the Southern California Edison utility turned off electricity to about 20,000 people in Los Angeles, Ventura, San Bernardino and Kern counties but warned that thousands more could lose service as the Santa Ana winds gained strength.

PG&E faced hostility and second-guessing over the shut-offs, which prompted runs on supplies like coolers and generators and forced institutions to shut down. The University of California, Berkeley, on Friday was closed for classes for the third day in a row. Also hit hard by the outages was California’s famed wine country area just north of San Francisco.

PG&E cast the blackouts as a matter of public safety, aimed at preventing the kind of blazes that have killed scores of people over the past couple of years, destroyed thousands of homes, and ran up tens of billions of dollars in claims that drove the company into bankruptcy.

The utility suggested it was already seeing the wisdom of its decision borne out as gusts topping 77 mph (122 kph) raked some hilltops where wildfire risk was extremely high.

“We have found multiple cases of damage or hazards” caused by heavy winds, including fallen branches that came in contact with overhead lines, said Sumeet Singh, a vice president for the utility. “If they were energized, they could’ve ignited.”

Utility CEO Bill Johnson promised if future wind events require similar shut-offs, the utility will “do better” when it comes to communicating with customers. It’s unacceptable that its websites crashed, maps were inconsistent and call centers were overloaded, Johnson said.

“We were not adequately prepared,” he said.

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