The San Onofre Nuclear Generating Station is poised to embark on a $280-million project to improve efficiency and safety at the plant.
For openers, workers will install new turbines, built with more aerodynamic blades to capture more steam energy, which will improve the plant's efficiency by about 40 megawatts, or 3 percent.
That might not sound like much, but because San Onofre generates so much electricity, 3 percent is enough to power 26,000 homes.
Also set for installation this year are two reactor heads that look like inverted steel bowls with dozens of tubes sticking out. Each tube contains a rod that moves up and down among the nuclear material in the reactors. This allows the nuclear reaction to take place, producing heat to boil the water. Steam from the boiling water turns the turbines to create electricity.
The new reactor heads have better alloys and fewer welds, improving safety and reducing inspection time, said Chief Nuclear Officer Pete Dietrich.
Southern California Edison spokesman Gil Alexander said Unit 2 at the plant is now running at 81 percent of capacity, winding down in preparation for the shutdown required to refuel and install the new components.
Identical new equipment at Unit 3 will be installed this fall, Alexander said.
Earlier, the plant Dietrich said the newest of those generators had been running more than 600 days without incident, other than when it shut down for a couple days in response to the massive September power outage throughout Southern California.