California power grid stretched thin by Oregon wildfire, heat wave

Californians responded to pleas from the state’s power grid operator to conserve energy usage Saturday after a fire in southern Oregon tripped interstate transmission lines, siphoning a “significant” amount of power as California endured a brutal heat wave.

The California Independent System Operator said during a Saturday news conference that three transmission lines on the California-Oregon Intertie were taken offline by the Bootleg Fire in southern Oregon — trimming the state’s available power by 5,500 megawatts.

On Sunday, the ISO said that while the transmission lines remained offline, the call for a third straight Flex Alert wasn’t expected.

Officials asked all residents Saturday to reduce power consumption quickly, warning that electricity supplies were being strained to a degree rarely seen. Californians responded, keeping the system in balance through the day’s peak load of 40,499 megawatts at 5:57 p.m.

SMUD-controlled line affected by Oregon fire

The Sacramento Municipal Utility District asked ratepayers to limit the use of electricity as temperatures zoomed to 113 degrees in Sacramento, a new daily record and the second-highest temperature in the city’s history.

SMUD also saw some loss of power from the Bootleg Fire but believes it has sufficient backup supplies to get through the heat, said utility spokeswoman Lindsay VanLaningham.

But blackouts couldn’t be ruled out, either, and the Sacramento Municipal Utility District appealed to its commercial and residential customers to scale back their power consumption in the late afternoon and evening hours.

“We’re not at a point of rotating outages right now,” she said. “That is our very last resort.”

“We do get some power from them,” she said, referring to the Oregon connections. “Those supplies have been curtailed. ... We have many other sources that we can get power from.”

SMUD isn’t part of the Independent System Operator grid and wouldn’t have to take part in any rolling blackouts called by the ISO. But the Sacramento utility has supplied the ISO with power during stressed periods, including last summer, VanLaningham said.

“SMUD continues to support the statewide electricity grid in the event of a true electrical emergency,” the utility said in its announcement, calling for residents to turn thermostats up to 80 degrees and avoid using household appliances between 3 and 9 p.m.

What does a Flex Alert mean?

A Flex Alert is in effect from 4 to 9 p.m. The advisory asks residents to voluntarily conserve energy by not running major appliances such as dishwashers, washing machines and electric dryers. State officials are also encouraging residents to set thermostats to 78 degrees to reduce the load used by air conditioners.

SMUD officials took it one step further with their call for customers to set thermostats at 80 or higher.

The utility suggested “limiting the use of both hot water and cold water (to) lower the demand for electricity needed for pumping, processing and delivery.”

Other tips recommended during a Flex Alert include turning off unnecessary lights, unplugging unused items, turning off swimming pool pumps and not charging electric vehicles. Fans should be used to keep areas cool while blinds and drapes should be used to keep sunlight from heating up interiors.

Consumers can learn more about Flex Alerts and sign up for alerts at flexalert.org.

Gov. Gavin Newsom, meanwhile, issued the second emergency proclamation in two days to help ease the power crunch.

On Saturday, he signed an executive order freeing up additional capacity allowing the use of auxiliary ship engines to “relieve pressure on the electric grid.” That came a day after relaxing some permitting requirements to free up additional energy supplies.

Officials from the Governor’s Office of Emergency Services also dispatched two additional strike teams to help battle the Bootleg Fire, bring the number of mutual aid crews in Oregon to four.

Stage 2 emergency briefly on Friday

The Independent System Operator issued a Stage 2 emergency alert Friday night and urged Californians to conserve energy as temperatures across interior California zoomed past 100 degrees. Downtown Sacramento tied its record high temperature of 109 at 5:25 p.m., according to the National Weather Service. The mark was previous reached on that day in 2002.

It was the first alert of this magnitude in 2021. A so-called Stage 2 was declared in August 2020, which was the first time the power grid had reached Stage 2 since a heat wave in 2006.

Stage 2 means consumption is so high that California has become “reserve deficient,” meaning in effect the state was eating into its margin for error. A Stage 2 gives the ISO the authority to order power generators that had been idle to start supplying electricity to the grid.

It’s also the last stage before the ISO would order rolling blackouts to keep the grid from failing.

Smoke and fire threaten power lines

The Bootleg Fire, which started Tuesday about 33 miles northeast of Klamath Falls, continues to burn in the Fremont-Winema National Forest. Authorities say strong winds have pushed the flames through heavy timber and brush, allowing the fire to double in size in 24 hours to nearly 77,000 acres.

“The fire will continue to move unchecked in all directions, with unstable air conditions and extremely dry fuels,” the U.S. Forest Service said in an incident update.

The ISO said the three transmission lines had tripped more than once and were taken offline because thick smoke was leading to the potential for arcing on the lines. Each alternating current line is operated by a separate agency, and ISO chief executive Elliot Mainzer said the fire was an event “beyond our control.” Another line, a direct current line feeding power to Los Angeles’ municipal utility had also lost capacity because of the smoke.

Officials said it was not known when the lines could safely be re-energized or if they sustained fire damage.

“It’s trajectory is unpredictable and at this point we have to be assuming that for the next few days that we’re going to be operating without it,” Mainzer said.

This is the third major heat wave already this year, and each has been accompanied by the grid’s Flex Alerts. In early July the System Operator appealed to power generators and traders to make more supplies available to California for the balance of the summer and early fall.

While grid managers said in May they were fairly sure the state could avoid blackouts this year, their confidence has waned as successive heat waves smother the state — and the drought has wiped out an estimated 1,000 megawatts worth of power at the state’s hydro plants.

Last summer California endured two consecutive nights of rolling blackouts during a 110-degree heat wave through much of the West. The grid is considered most vulnerable after the sun goes down, solar generation fades, but it remains hot.

This story was originally published July 9, 2021 at 8:26 PM with the headline "California power grid stretched thin by Oregon wildfire, heat wave."