October 1, 2022

In 3 cities, electricity may have been cut unnecessarily to houses

California’s power grid survived Tuesday’s blackouts and may be near the brink again Wednesday and Thursday as demand remains at unprecedented levels in the extreme heat.

But some Northern California cities experienced blackouts on Tuesday anyway, a fault stemming from a miscommunication between a utility group at the California Independent System Operator, operator of the state’s electric grid.

At least three Bay Area cities began rolling outages Tuesday night — Alameda, Healdsburg and Palo Alto. Each is a member of the Northern California Power Agency, or NCPA, the nonprofit Joint Power Commission.

The rotating outages in several California municipalities Tuesday night were not ordered by the grid operator, California ISO CEO Eliot Mainzer said in a media call Wednesday. He said the NCPA membership defection was a result of confusion and misunderstanding.

“These are obviously very rare situations, and there was a lot going on for everybody last night. So we’re going to redouble communications to make sure it doesn’t happen again,” Mainzer said.

According to an NCPA statement released Wednesday afternoon, California ISO contacted NCPA’s dispatch center at 5:53 p.m.

“Once the outage was initiated, our dispatcher contacted CAISO and was informed that the curtailment action had been taken, and then informed that there was a misunderstanding of the initial order. At that time, we immediately began the process of getting the load back into the system,” the NCPA statement said.

The NCPA said the outages of its member utilities “ultimately may have helped prevent heat-related impacts to the state’s overstressed grid,” adding that accidental rotating outages may have helped the state’s grid operator avoid an intentional rotating outage. Power demand is greater than supply.

But on Wednesday morning, when asked if inadvertent outages could help keep the grid afloat, Mainzer replied: “Absolutely not.” Instead, he said the drop in demand after the state sent an emergency text warning around 5:45 p.m. asking Californians to conserve power was enough to bring the grid back from the brink of rolling blackouts.

Lodi, in San Joaquin County, was a member of the NCPA and started the strike. Resident Larry Whited was one of thousands of customers affected. White said he received a text about ten minutes after the power outage: “The CAISO system has declared an emergency. Lodi is required to dump loads. A one (1) hour power outage will occur in your area within 30 minutes. For medical emergencies, call 911.

His power was out for about 45 minutes, Wittet said. Whited said he was angered by media reports and official statements that said there were no rotating outages in California Tuesday night.

“Gavin Newsom Tweeted “There were no emergency shutdowns, but I knew there were because I was in one of them,” Witt said.

The California ISO said at 5:30 p.m. Tuesday that electricity was running low amid unprecedented demand as California’s record-setting heat wave strained the grid. The Independent System Operator moved to Level 3 emergency operations, allowing utilities to order to initiate shutdowns if necessary.



Further Strains in electrical grid Wednesday occurred when peak demand was forecast at 51,243 MW — not far off Tuesday’s record of 52,061 MW. (Going above 50,000 megawatts is rare.) Another flex alert asking residents to conserve power is between 4 p.m. and 9 p.m. Thursday when demand is expected to peak above 50,000 megawatts.

NCPA members include Lodi, Alameda, Healdsburg, Palo Alto, Santa Clara, Biggs, Gridley, Lompoc, Redding, Roseville, Shasta Lake and Ukiah.

In a Facebook post Tuesday night, Alameda said the California ISO “has issued a Level 3 Alert from 6-8pm today, which begins our rolling outage. We have had to close 2 circuits, Marina Village and East End, and will have power outages for 45-60 minutes.

The city utility reported a second-hour outage on Bay Farm Island.

Alameda Municipal Power Published In a statement Wednesday morning, NCPA instructed Alameda to shed loads around 5:45 p.m., resulting in power outages for 1,400 customers between 6:05 and 7:05 p.m. “If NCPA instructs to shed loads, AMP must operate,” the statement read.

“We are working with CAISO and NCPA to clarify procedures to ensure that there are no unnecessary outages moving forward,” the statement said.

The city of Healdsburg said Tuesday at 6:20 p.m. it was advised by the California ISO to shut off power for one hour. About 90 minutes later, the city said the power outage was due to low system load.

Palo Alto Utilities, the city’s municipal operator, said the power outage was in response to state efforts to reduce power demand around 6:30 p.m. About 1,700 customers in Midtown, Old Palo Alto and Industrial Park were affected by the outage, the agency said. About half an hour later, the utility said power was restored after the California ISO gave the go-ahead.

Jordan Cowman, a spokesman for Palo Alto Utilities, said it was one of several utilities contacted Wednesday. He said he hopes the NCPA and California ISO work together.

“We (shut off power) to our utility for the requested amount and then gave the all clear,” Cowman said.

Power was restored shortly after 7 p.m. after the NCPA told Lodi that its power agency, Lodi Electric, was asked to shed loads at 6 p.m. Tuesday, and then at 6:20 p.m., 1,372 customers in several neighborhoods were without power. According to City of Lodi Public Information Officer Mary Campbell, we were able to restore power and we were prepared.

But around 8:30 p.m., Lodi officials learned on the city’s Facebook page that the “load shed order for Lodi was in error.”

“The NCPA reported that there was a communication error between Lodi Electric and Cal ISO, causing the NCPA to issue the directive to Lodi and other NCPA members,” the city said.

Some residents across California experienced unscheduled outages during the heat wave, including at several utilities, including Pacific Gas & Electric Co., as the high temperatures caused electrical equipment such as transformers to malfunction. These are different from rolling blackouts or pre-planned outages to reduce wildfire risk.

Jessica Flores (she/her) and Claire Haw are San Francisco Chronicle staff writers. Email: [email protected], [email protected], Twitter: @jesssmflores, @clairehao_