The California Public Utilities Commission has voted to open a financial probe into rising costs tied to the damaged San Onofre nuclear power plant, which has been shut down for most of the year.
The five-member commission's vote Thursday was unanimous.
So far, the bill has reached at least $165 million for repairs, inspection and replacement electricity. The twin-reactor plant hasn't produced power since Jan. 31 due to crippled steam generators.
It's not clear when, or if, the reactors will return to service.
The commission determines how much utilities can charge homeowners and businesses for electricity.
The plant is owned by Southern California Edison, San Diego Gas & Electric and the city of Riverside.