A massive power outage in San Francisco, California, has produced contrasting fortunes for robotaxi operators. When traffic lights went dark and an unprecedented situation unfolded, Google's driverless Waymo vehicles had to suspend operations. Tesla's robotaxis, which have human operators on board, continued running as drivers could make judgment calls amid the chaos.
Waymo announced through its service application on January 21 that it was temporarily suspending rides in San Francisco. The move came after Waymo vehicles were seen frozen on roads when traffic lights went out due to a blackout that began the previous day.
Waymo spokesperson Susan Phillion explained the suspension in an emailed statement to CNBC. "Yesterday's outage caused traffic disruptions across San Francisco, with traffic signals going out and public transit impacted," she said. "While the infrastructure failure was significant, we'll continue working to ensure our technology adapts to traffic conditions when such situations arise."
Tesla, Waymo's competitor, was unaffected by the outage. CEO Elon Musk wrote on X that morning, "Tesla robotaxis were not affected by the SF power outage."
According to local media, a massive blackout struck the San Francisco area at approximately 1:09 p.m. the previous day, affecting about 130,000 households including commercial facilities. That represents 30% of the entire city. Pacific Gas & Electric, the regional power provider, reported that nearly half of the northern part of the city, including the Richmond and Sunset districts, lost power. The outage was attributed to a substation fire.
The blackout caused particular chaos at intersections where traffic lights went dark. Videos circulated on social media over the weekend showing confused Waymo vehicles unable to proceed without traffic signals. San Francisco residents reported that "Waymo taxis were stopped in the middle of the road."
Phillion told CNBC that "Waymo is designed to treat non-functioning signals as four-way stops, but given the scale of this outage, vehicles had to remain stationary longer than usual to assess intersection conditions." She added that "this exacerbated traffic congestion and added to the gridlock."
The divergent responses of Waymo and Tesla robotaxis during the blackout stem from their different operating modes. Waymo operates fully autonomous vehicles with no one in the driver's seat, while Tesla robotaxis use supervised Full Self-Driving (FSD) software with a safety operator behind the wheel. Supervised FSD requires drivers to constantly monitor driving conditions and intervene by steering or braking when necessary.
According to CNBC, Tesla has not yet received approval in California to operate FSD services without a safety supervisor on board. Even in areas where Tesla has permits, it operates robotaxis with drivers present. Waymo has captured the autonomous vehicle market using lidar technology, which employs high-precision image sensors to detect surroundings. Tesla, the latecomer, is catching up with a camera and artificial intelligence-based approach.
