A Central California nuclear power plant has shut down one of its two generators after an electrical arc occurred during a storm.
Unit 2 at Diablo automatically went offline Sunday.
Pacific Gas & Electric spokesman Blair Jones says a flashover, or electrical arc, occurred from a buildup of dust mixed with moisture on a lightning arrestor. The arrestor is on a non-nuclear part of the plant that helps transmit power to the state's electric grid.
Jones says the event happened as the drought-stricken area got its first heavy rain in a long time.
Jones says Unit 2 will remain offline until the incident is investigated and the lightning arrestor is repaired and tested. However, he says the shutdown won't affect electrical supplies to PG&E customers.