Diablo Canyon nuclear power plant is back to full power Thursday morning after repairs were completed on a main feed water pump.
One of the plants two reactors was reduced to half power Monday afternoon to perform repairs after the pump malfunctioned. The plants other reactor continued to run at full power throughout the repairs.
Main feed water pumps are part of the non-nuclear, steam side of the plant. Their purpose is to increase the pressure of water high enough to enter the steam generators, which transfer heat from the reactor.
In addition to the two main feed water pumps, there are three backup auxiliary feed water pumps.