San Francisco Power Outage Cripples City, Strands Autonomous Vehicle Fleet

A massive power outage struck San Francisco on Saturday, December 20, 2025. It plunged large sections of the city into darkness. The blackout impacted approximately 130,000 customers and caused major traffic chaos.

The widespread failure of traffic signals created dangerous and confusing conditions for drivers. Autonomous vehicle company Waymo was forced to suspend its entire ride-hailing service in the city. Videos shared online showed multiple Waymo cars stranded at intersections.

According to reports from local media, the company made the decision for safety. A Waymo spokesperson cited the need to ensure clear access for emergency personnel. The halt in service was described as temporary.

The cause of the blackout was linked to a fire at a PG&E substation. The San Francisco Fire Department responded to the incident at 8th and Mission Streets. Officials confirmed the fire was largely contained and caused no injuries.

Waymo’s Stranded Vehicles Highlight Grid Vulnerability

The incident provided a stark real-world test of autonomous vehicle systems during infrastructure failure. Without functional traffic lights, the Waymo vehicles entered a safety protocol. This protocol involved coming to a stop, which contributed to traffic snarls.

Social media posts depicted scenes of the driverless cars idling at dark intersections. Other human-driven vehicles were also shown stopped or moving cautiously. The gridlock underscored the city’s dependence on a functioning electrical grid.

Pacific Gas & Electric provided limited information on restoration efforts. The utility stated power could be restored later that day but could not confirm a timeline. This left residents and businesses without a clear estimate for the lights coming back on.

The event is likely to fuel ongoing debates about urban infrastructure and new technology. Critics of autonomous vehicle expansion may point to the disruption as a significant risk. Proponents will likely argue the vehicles acted safely in an unprecedented situation.

City Left Seeking Answers After Major Infrastructure Failure

The scale of the outage disrupted commerce, transit, and daily life across San Francisco. Restaurants and stores were forced to close or operate in limited capacity. Public transportation systems also experienced significant delays and cancellations.

Public safety agencies were placed on high alert throughout the duration of the blackout. Emergency generators provided power to critical facilities like hospitals. Police directed traffic at some major intersections to mitigate the confusion.

The fire at the PG&E substation remains under investigation. Authorities have not yet released a definitive cause for the blaze. The utility company is expected to face scrutiny over the resilience of its infrastructure.

For residents, the event was a sudden and jarring reminder of modern vulnerabilities. The **San Francisco power outage** demonstrates how a single point of failure can ripple through an entire metropolitan system. The city will now examine how to better prepare for similar future crises.

References: Associated Press (AP), Mission Local, The San Francisco Standard.