Southern California Edison is ramping up the number of crews available to respond to possible power outages as sweltering temperatures send electricity use climbing.
The company said Wednesday that high electricity use -- particularly from air conditioners -- is straining distribution equipment, but no power outages have been reported.
Local officials have been preparing for months to handle tight power supplies after the San Onofre nuclear power plant shut down in January following a break in a tube that carries radioactive water.
The company is urging customers to conserve power as triple-digit temperatures bake the region's valleys and inland areas including the deserts.
Southern California Edison is a unit of Edison International that serves an area with nearly 14 million people.