A major power failure in San Francisco has exposed critical vulnerabilities in the emergency response capabilities of autonomous vehicles, triggering renewed demands for stricter oversight of the rapidly expanding robotaxi industry. The incident, which occurred on December 20, saw multiple driverless taxis from Alphabet's Waymo stall at intersections, contributing to significant traffic congestion.
Blackout Chaos Highlights Systemic Weakness
Videos shared on social media captured the chaotic scene after a fire at a PG&E substation cut power to roughly one-third of San Francisco. Waymo's ubiquitous robotaxis, a common sight on the city's streets, were left stranded at non-functioning traffic signals with their hazard lights activated. The company was forced to halt its entire service for a day before resuming operations.
While Waymo stated that its vehicles are programmed to treat non-operational traffic lights as four-way stops, the scale of the outage overwhelmed the system. The company revealed that its fleet successfully navigated over 7,000 darkened signals that day. However, the blackout caused a massive, concentrated spike in requests for remote confirmation from human operators, leading to delays that snagged traffic on already overwhelmed roads.
Experts Demand Regulation of Remote Assistance
The event has turned the spotlight on "teleoperation"—the remote human monitoring and control of autonomous vehicles. Professor Missy Cummings, Director of the George Mason University Autonomy and Robotics Center and a former advisor to U.S. road safety regulators, argued that the incident underscores an urgent need for federal rules.
"The whole point of having remote operations is for humans to be there when the system is not responsive in the way it should be," Cummings said. She stressed that regulators must ensure backup systems are in place for catastrophic failures like earthquakes or floods.
Echoing this sentiment, Carnegie Mellon University professor and autonomous technology expert Philip Koopman warned that regulators would be "derelict" if they did not now require proof that such large-scale emergency scenarios can be handled safely. "If this had been an earthquake, it would have been a problem. This is just a shot across the bow," he stated.
Industry at a Crossroads: Expansion vs. Safety
The push for commercialization of fully autonomous vehicles has proven challenging, marked by high safety investment costs and public backlash following accidents. The industry faced a major setback in 2023 when a Cruise robotaxi from General Motors dragged a pedestrian, leading to a revoked permit and a cessation of its operations.
However, the race is heating up again. Tesla has launched its robotaxi service in Austin, Texas, with CEO Elon Musk promising rapid growth. Waymo, which began as Google's self-driving project in 2009, is also accelerating its expansion. It now operates a fleet of more than 2,500 vehicles across the San Francisco Bay Area, Los Angeles, Metro Phoenix, Austin, and Atlanta.
In response to the blackout, Waymo announced it is implementing fleet-wide software updates. These will provide vehicles with "specific power outage context," enabling them to navigate more decisively in similar future situations.
California regulators are now scrutinizing the event. The Department of Motor Vehicles (DMV) and the California Public Utilities Commission (CPUC), which oversee robotaxi testing and permits, have confirmed they are investigating. The DMV added that it is formulating regulations to ensure remote drivers meet high standards for safety, accountability, and responsiveness.
Both Cummings and Koopman advocate for a tiered regulatory approach, suggesting that robotaxi operators should face additional permitting requirements once their fleets grow beyond a certain size. This would ensure they possess the scalable capability to manage large-scale system failures, a crucial test for an industry aiming to redefine urban mobility.
