Power went out in parts of San Francisco Saturday afternoon after a fire at a substation.
A fire at a Pacific Gas & Electric substation in SoMa knocked out power to as many as 130,000 customers starting Saturday, leaving thousands in the dark heading into the holiday season and a week of intense storms…
The fire began shortly before 1:10 p.m. Saturday at PG&E’s Mission substation at Eighth and Mission streets, initially affecting 40,000 customers. As firefighters worked to suppress the blaze, crews de-energized additional portions of the electric system for safety, causing outages to peak at approximately 130,000 customers.
The fire damaged critical equipment, including a circuit breaker — a safety switch designed to de-energize the system when problems are detected. Firefighters faced unusual complexities suppressing the fire in the multilevel building, including ventilating carbon monoxide before crews could safely enter.
The fire wasn’t put out until around 6pm and then the building was too full of carbon monoxide for workers to enter and start on repairs.
Of course power problems can happen anywhere but it’s a bad sign when it takes your city more than 48 hours to get the power back on. In fact, one of the things that most irritated PG&E customers was the constantly changing estimates of when the power would be back on. Those estimates kept being extended.
Many customers were irate as they were repeatedly given estimated restoration times that came and went. Singh acknowledged the failure and said PG&E’s estimation systems typically perform well, with more than 91% accuracy systemwide.
“It obviously did not work effectively in the circumstance over this weekend,” Singh said. “We are committed to understanding exactly what happened, why it happened, and owning the fixes.”
So after going down early Saturday afternoon, power was finally restored to everyone early Tuesday morning.
As of 4:31 a.m. Tuesday, electricity had been restored to the final 3,800 customers who were still without power following the outage caused by a fire at a San Francisco substation, PG&E said. At the height of the outage Saturday afternoon, about 130,000 customers across the city lost power, including many in the Civic Center and Richmond District.
For some residents, including those living in tall apartment buildings, having the power out was a major problem. With the power out elevators and even the water supply stopped working.
Heidi King’s exciting move into a new apartment at the NEMA building at 8 10th St. turned into a nightmare when the mass blackout that started Saturday afternoon left her and her neighbors without electricity, water, or working elevators.
King and her partner were settling into their 18th-floor unit when the power cut off. With the elevators out of commission, the movers ended up dumping the couple’s possessions in the parking area on their way out.
“We were left with nothing,” King said. The couple spent the first night in their new home sleeping on the floor, with no water, forcing them to leave the building to use the bathroom…
One of King’s neighbors at the NEMA building, Annie Benisch, spent two days camping in her apartment, throwing away hundreds of dollars’ worth of holiday groceries while receiving inaccurate estimates from PG&E about when power would be restored.
The power outage also created another problem. San Francisco has about 1,000 driverless Waymo taxis and during the power outage they shut down and simply stopped moving in the middle of the street.
Bad day to be a Waymo (and even worse to be inside or stuck behind one). A widespread blackout left robotaxis stalled across the city, causing traffic chaos Saturday night.
Read more: https://t.co/gHUtq7G03J pic.twitter.com/hfOIVfhKpE
— The San Francisco Standard (@sfstandard) December 21, 2025
In addition to having fewer taxis available, this also create traffic jams in some places.
Waymo’s self-driving cars were put on pause by the company on Saturday in San Francisco after the autonomous vehicles were baffled by the lack of traffic signals due to a widespread power outage in the city. https://t.co/t6NgkBCTe7 pic.twitter.com/cXoK0yuvTw
— ABC News (@ABC) December 21, 2025
Waymo obviously knows why they shut down their fleet, but so far they aren’t saying. Nevertheless, people are speculating and some of this makes sense.
It remains unknown exactly why the Waymos stalled. Some experts speculated that the vehicles rely on cell service to communicate with remote operators in emergency situations, and that their connections dropped in the outage. Others have said that the company may have purposely shut down the cars because it was too risky to have them navigate through so many dead traffic lights.
It is not clear that self-driving technology itself was to blame. Elon Musk said on X that Tesla Robotaxis, which provide limited ride-share services in San Francisco, had been unaffected this weekend. (The Tesla service is still required to have a human safety monitor on board.)
Waymo said in a statement that while its vehicles are designed to treat nonfunctional signals as four-way stops, “the sheer scale of the outage led to instances where vehicles remained stationary longer than usual to confirm the state of the affected intersections. This contributed to traffic friction during the height of the congestion.”
Waymo’s don’t have safety drivers in the cars but they do have remote safety drivers who can teleoperate the cars in case of a problem. In this case, it seems likely that cars stuck in areas with no cell service were suddenly cut off from those human operators and left to operate on their own. Maybe the cars couldn’t handle it or maybe they were told to stay put where they were to avoid creating an incident. Either way, they were worse than useless. Many people began wondering what would happen after a major earthquake. Would Waymos all shut down and create a problem for emergency vehicles?
Tesla also offers a robotaxi service in the city and there vehicles apparently kept going in the dark. This shows a car still using self-driving despite the power outage.
During the San Francisco power outage, Tesla’s FSD seamlessly handled dead traffic lights as all way stops, navigating through the chaos without issue.
Something Waymo couldn’t!!!! https://t.co/jsGwHONWvu pic.twitter.com/l6KyGGPmmc
— Teslanomy (@Teslanomy_com) December 21, 2025
Tesla taxis still have a human driver in the front seat so it’s hard to know if the human driver had to take over in some cases. In any case, not a great weekend for the city. Lots of people will be getting $200 credits from PG&E and some kind of investigation into the fire will be undertaken. But don’t expect any clear answers anytime soon. When something goes wrong in a blue city no politician is going to point fingers as union workers as part of the problem.
