Waymo vehicles are operating again in San Francisco following a power outage

Waymo has resumed its robo-taxi service in San Francisco after a power outage stranded vehicles around the city, CNBC reported. The blackout, caused by a Pacific Gas & Electric (PG&E) substation fire, caused traffic light disruptions that affected Waymo’s automated driving systems.

“Yesterday’s power outage was a widespread event that caused gridlock across San Francisco, with non-functioning traffic signals and transit disruptions,” a Waymo spokesperson told CNBC in a statement. “While the failure of the utility infrastructure was significant, we are committed to ensuring our technology adjusts to traffic flow during such events.”

Following the outage, which began at around 1:09 PM Saturday and peaked around two hours later, Waymo responded by suspending its ride-hailing services in the city. However, images and videos on social media showed the autonomous taxis stopped at intersections with hazard lights on.

The company blamed its disruption on the size of the outage. “While the Waymo Driver [automated system] is designed to treat non-functional 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,” the spokesperson explained, adding that Waymo’s actions were “closely coordinated with San Francisco city officials.”

Still, the service disruption is a black mark for Waymo, as the sudden halt in service exacerbated traffic problems caused by the blackout. Elon Musk bragged on X that Tesla, Waymo’s latest robo-taxi rival in the city, was “unaffected” by the power outage. However, Tesla’s ride-hailing service is not yet fully autonomous and requires a human driver behind the wheel at all times.