SAN FRANCISCO — Many of Waymo's self-driving cars blocked streets of San Francisco during a mass power outage Saturday and forced the company to temporarily suspend service, raising questions about the cars' ability to to adapt to real-world driving conditions.
Social media users posted videos of Waymos as they encountered traffic lights that were off. Some cars' hazard lights blinked and they abruptly stopped in place, failing to cross the intersection. Others stopped in the middle of the intersection, forcing other cars to swerve around them.
The power outage affected 130,000 homes and businesses in San Francisco, nearly one-third of the customers served by Pacific Gas and Electric Co. It was caused by a fire at a power substation, officials said. On Monday, the utility company was still working to restore power to thousands of customers.
Waymo operates hundreds of robotaxis in San Francisco, but it wasn't clear how many cars were on the road at the time of the outage. The company paused service Saturday evening and resumed it Sunday afternoon.
The road-blocking problems that prompted Waymo to suspend its service during the weekend power outages revived concerns that city officials raised about the robotaxis periodically coming to abrupt and inexplicable stops before California regulators approved them as a commercial service in August 2023.
Tyler Cervini, who lives in the Mission District, said he was calling an Uber to bring him to the airport since his train station was not operating due to the outage. At the traffic light outside his apartment, there were five Waymos crowding the intersection, he said.
He got into his Uber right outside where all the Waymos were, but his driver "had to swerve through them to pick me up," Cervini said. ''He seemed extremely frustrated by what was going on.''
Waymo said that its vehicles are designed to treat nonfunctioning traffic signals as four-way stops, but the scale of the outage created unusual conditions.