Steam Generators

The problems at the San Onofre nuclear power plant are serious enough that the facility will not be able to operate at full capacity when it reopens, perhaps as early as June. The announcement comes as officials continue to investigate problems in the reactors that have forced the plant to remain shut for three months, the longest closure in San Onofre's history. Southern California Edison estimated that the company's cost for inspections and repairs at the plant would be between $55 million and $65 million.

California energy officials are preparing for another summer without the San Onofre power station while facing the growing possibility that the nuclear plant will never return to service. The nuclear plant, one of only two in the state, was powered down more than a year ago when a small amount of radioactive mist leaked from one of the thousands of tubes in the plant's steam generators. Southern California Edison officials said in financial statements last week that if federal regulators do not agree to the utility's proposal to restart one of the plant's two units at partial power, they might elect to retire the plant completely by the end of the year.

The U.S. Nuclear Regulatory Commission, citing serious concerns about equipment failures at the San Onofre nuclear power plant, has prohibited Southern California Edison from restarting the plant until the problems are thoroughly understood and fixed. The plant has been shut down for two months, the longest in San Onofre's history, after a tube leak in one of the plant's steam generators released a small amount of radioactive steam. Since then, unusual wear has been found on hundreds of tubes that carry radioactive water.

The parent company of Southern California Edison, operator of the troubled San Onofre nuclear plant, reported that the costs of the yearlong outage at the plant had ballooned to more than $400 million by the end of 2012. The hefty price tag for the darkened plant includes inspections, repairs and purchasing replacement power. Edison International officials fielded questions Tuesday from analysts about the plant's extended shutdown and the possibility that federal regulators will require the plant to go through a lengthy license amendment process before returning to service.

San Onofre's two nuclear-power units have been down for months and will stay that way for months more. Late last week, Southern California Edison officials acknowledged that after early hopes that the reactors would be running safely in time for the summer energy load, it isn't going to happen. They'll have a plan by midsummer for reopening Unit 2, but then the plan will have to go through the lengthy regulatory process. And no one seems even remotely confident of when Unit 3 might return, and if it does, at what level of power?

A report on the root causes of problems at the San Onofre nuclear power plant shows that officials considered making design changes to its new steam generators before they were installed but rejected some fixes in part because they would require further regulatory approvals. Some of the generators began to malfunction a year after they were installed, and the plant has been shuttered for 13 months. The closure has already cost San Onofre's owners, Southern California Edison and San Diego Gas and Electric, more than $470 million.

State regulators Thursday approved a massive project to replace deteriorating steam generators at the San Onofre Nuclear Generating Station, a plan that could extend the plant's operation by at least 13 years. The California Public Utilities Commission also capped the amount Southern California Edison Co. could collect from its customers to pay for the project, which will cost at least $680 million.