Massive Power Outage Plunges San Francisco into Darkness, Stalls Robotaxis

A major power outage struck San Francisco this week, leaving over 130,000 residents and businesses without electricity and causing widespread disruption, including the complete immobilization of the city's driverless taxi fleet.

The blackout, which at its peak affected nearly one-third of the city, was caused by significant damage at a key Pacific Gas and Electric (PG&E) substation [31639]. The utility provider reported the damage as "significant and extensive," leading to a prolonged loss of power across multiple neighborhoods [31392][31470]. City officials advised residents to avoid non-essential travel as traffic signals failed and public transportation experienced major delays [31392][31540].

The widespread infrastructure failure had a direct and visible impact on emerging technology. Waymo, a leading operator of autonomous vehicles, was forced to proactively halt its entire fleet of robotaxis—cars that operate without a human driver—as a standard safety precaution [31561][31871]. The vehicles, which rely on functioning traffic signals and clear environmental rules, became stationary obstacles when they could not interpret the darkened intersections, leading to traffic snarls [21410][31871].

"The cars are programmed to stop for safety when they cannot understand traffic signals," a company spokesperson explained. This event underscores a critical challenge for self-driving technology: its dependence on predictable infrastructure [31871]. The robotaxis remained out of service until power was restored and city signals began working again [31871].

Utility crews worked through the event to restore service, though the exact cause of the substation damage remains under investigation [31639]. Authorities continue to remind the public to treat non-functioning traffic signals as four-way stops during such outages [31470].