California avoids outages after grid-straining heat

LOS ANGELES (AP) — California avoided rolling outages during extreme heat, as operators of the state's electricity grid continued to warn that unprecedented demand on energy supplies could force them to periodically cut power to some customers.

The California Independent System Operator on Wednesday thanked residents and businesses for heeding another "flex alert," a request to reduce electricity consumption during peak evening hours.

"With your help, we made it through another day without rotating #poweroutages," Cal-ISO said on Twitter. Another flex alert was issued for Thursday from 3 p.m. to 10 p.m. as temperatures were expected to spike again.

Targeted blackouts were avoided a day after miscommunication led utilities to mistakenly cut power to customers in several California cities.

The confusion occurred Tuesday afternoon between a dispatcher at the Northern California Power Agency, which owns and operates power generating facilities for 16 members including a dozen cities, and the California Independent System Operator as the grid it manages was perilously close to running out of energy amid record-breaking temperatures.

"That is certainly concerning to me," Elliot Mainzer, president and CEO of Cal-ISO, said Wednesday. "There was a lot happening on the grid for everybody last night. And so we'll double down on the communication to make sure that doesn't happen again."

With record demand on power supplies across the West, California snapped its record energy use around 5 p.m. Tuesday with 52,061 megawatts, far above the previous high of 50,270 megawatts set July 24, 2006.

As residents and businesses cranked air-conditioning to escape withering heat across the West and solar power supplies began to wane, Cal-ISO issued a stage 3 energy emergency alert to prepare utilities to initiate outages if demand didn't decrease. The state's legal marijuana regulatory agency also urged businesses to turn off lights and reduce power or use backup generators.

The Northern California Power Agency said its dispatcher misinterpreted Cal-ISO's order to prepare to cut power and immediately undertook the process to cut 46 megawatts — enough to serve about 35,000 customers — in the cities of Alameda, Lodi, Santa Clara, Palo Alto, Healdsburg, and Ukiah.