PG&E may refund customers $43 million for unplanned outage at Diablo power plant
PG&E may refund ratepayers $43 million — the cost of replacement power delivered across California when Unit 2 of the Diablo Canyon nuclear power plant shut down unexpectedly for repairs in 2021.
Unit 2 of the power plant closed for repairs four times in 2020 and 2021, forcing PG&E to buy replacement power to keep its customer’s lights on.
PG&E charged ratepayers for that power, but two administrative judges said the utility company should foot the bill for the fourth outage, the May 12 proposed decision said.
According to the judges, the fourth outage could have been prevented if PG&E had properly tested the equipment in the Unit 2 generator — and PG&E shouldn’t charge customers for the company’s mistake, the judges said.
They advised the California Public Utilities Commission to order PG&E to refund ratepayers for the cost of replacement power delivered when Unit 2 shut down from Feb. 2, 2021, to March 1, 2021.
The commission is expected to vote on whether or not to enforce the order at its June 26 business meeting.
Alliance for Nuclear Responsibility executive director David Weisman said the proposed decision was a victory for ratepayers.
“PG&E is finally being taught that they can’t make colossal blunders and expect that to be on the backs of already financially struggling utility ratepayers,” he told The Tribune.
PG&E, however, was “disappointed” by the proposed decision, company spokesperson Suzanne Hosn wrote in an email to The Tribune.
“We are confident we took the right steps to ensure safe and reliable operation of Diablo Canyon to support overall grid reliability,” she wrote. “This example demonstrates our commitment to safety: We closely monitor after work is performed to confirm it meets our rigorous standards and take proactive steps as necessary to ensure long-term safe and reliable operation.”
PG&E will file a response to the proposed decision on June 2, Hosn said.
If the commission orders PG&E to issue the refund, ratepayers won’t get a check in the mail.
Instead, ratepayers would notice a temporary reduction in rates designed to compensate for the $43 million, commission communications director Terrie Prosper said.
This would appear as the “Power Charge Indifference Adjustment” on each customer’s bill, she said.
Unplanned outages at the power plant
The Diablo Canyon nuclear power plant is nestled into the hills of Avila Beach. At the facility, nuclear reactions inside two core reactors power steam turbines, which generate electricity.
On four occasions, PG&E shut down Unit 2 due to “excessive vibrations” in the stator, which is a key component of the electric generator on the non-nuclear side of the plant, the proposed decision said.
The judges said PG&E could charge ratepayers for the first three outages, which lasted from July 17, 2020, to Aug. 2, 2020, then Oct. 15, 2020, to Nov. 26, 2020, and Dec. 2, 2020, to Jan. 12, 2021.
Those outages were fixed by tightening the necessary bolts, the proposed decision said.
But the fourth outage, which lasted from Feb. 2, 2021, to March 1, 2021, could have been prevented by proper design verification testing, the judges said.
The judges advised the commission to order PG&E to return $43 million to ratepayers to compensate for that outage.
Weisman said he’s glad the judges held PG&E accountable for its mistake, and he hopes the commission enforces the decision. Still, he’s concerned that as the power plant ages, it will shut down for repairs more frequently — degrading its reliability.
“The real issue is this: The machine is getting old,” Weisman said. “As they look to extend the life of the plant and need to replace multiple systems, how can we be assured that these problems and these mismanagement and oversight concerns won’t be cropping up again?”
Hosn, however, noted that the U.S. Nuclear Regulatory Commission certified and regularly inspects the power plant.
“Time and time again, these inspectors have determined that the plant is safe to operate,” she said, “and the NRC’s assessments have placed it among the highest performing plants in the nation.”
This story was originally published May 19, 2025 at 1:30 PM.
