Crews are performing maintenance work at the Diablo Canyon Power Plant this weekend.
According to PG&E, operators safely removed Unit 2 from service Friday in order to perform maintenance on the main generator hydrogen system.
This work cannot be performed while the unit is operating, a PG&E spokesperson said in a press release.
PG&E officials say there is no impact to the health and safety of the public and there will be no disruption in electric service to customers.
The two units at Diablo Canyon Power Plant operate independently, and Unit 1 remains safely operating at full power, according to PG&E.
Once work has been completed, Unit 2 will be returned to service.
Diablo Canyon Power Plant is a nuclear power facility owned and operated by PG&E. Its two units together produce approximately 2,300 net megawatts of carbon-free power.