A wildfire is pushing California towards the brink of blackouts

Wildfires burned an unprecedented 4.3 million acres across California in 2020. PHOTO: AFP

CALIFORNIA (BLOOMBERG) - A wildfire raging uncontrollably across southern Oregon has knocked out three electrical lines so critical to the stability of grids in the western US that California has warned of rotating blackouts and Nevada faced a power emergency.

The fast-moving Bootleg fire has crippled a key transmission system known as the California Oregon Intertie that the Golden State has depended on for years for electricity imports.

Making matters worse: The takedown of the intertie has had a knock-on effect on another key import hub known as the Pacific DC Intertie that brings in electricity from the Pacific Northwest, California's grid operator said in a media briefing on Saturday (July 10).

In all, California has lost 5,500 megawatts of power-import capacity - enough to light up roughly 4.13 million homes.

The fact that a single wildfire has brought America's most populous and affluent state to the brink of blackouts is among the most powerful demonstrations yet of how vulnerable the world's power grids have become to the effects of climate change.

Extreme heat, drought and dry conditions globally have shrunk hydropower reserves, driven up electricity demand to record levels and touched off some of the worst wildfire seasons in modern history.

Climate change is "forcing us to do things we never imagined" at this time of the year, said Elliot Mainzer, who took over as chief executive officer of grid manager California Independent System Operator nine months ago. The agency is "anticipating what could be a very long and hot summer", he said.

California has emerged as the epicentre of climate disasters in the United States. Wildfires burned an unprecedented 4.3 million acres across the state last year, killing 33 people and scorching nearly 10,500 structures.

In August, California suffered its first rolling blackouts since the US West energy crisis two decades ago because of extremely hot weather. And in a foreshadowing of what was to come: Days before this year's summer officially began, high temperatures forced the California ISO to make an unusually early call for conservation, allowing the region to duck another round of rotating outages.

"Bottom line is we took everything we learned from last summer, and we still came into this summer thinking our issues were going to primarily be associated with August and September," Mainzer said, but "we had the first major heat wave four days before the official beginning of summer".

On Friday evening, the grid operator took the rare step of ordering a Stage 2 emergency - one step away from rotating blackouts - to cope with the loss of import capacity. Energy conservation helped the state avert a crisis. But as temperatures rose yet again and supplies fell off the grid Saturday, Mainzer said, "We're going to need more. Honestly, I think we are going to need more response than we saw last night."

The grid operator called off the flex alert shortly after 9pm Saturday on the West Coast.

Earlier in the day, Governor Gavin Newsom also signed an order to free up more energy capacity to help alleviate the supply crunch.

California wasn't the only state facing power woes on Friday evening. Nevada's power system was among those in the region that also faced emergency levels, said Mark Rothleder, California's ISO's chief operating officer. On top of managing California's grid, the agency serves as a reliability coordinator and is responsible for monitoring conditions across the western region.

Nevada utility NV Energy said it wasn't forced to resort to blackouts, but the company was calling for customers to conserve over the weekend.

Exactly when the Bootleg fire would subside enough to re-energise the California Oregon Intertie remains to be seen. Mainzer said it was possible the lines would return to service on Sunday at midnight local time, but the grid operator was operating under the assumption that the system would remain down.

The Bootleg fire had burned through 76,897 acres of southern Oregon and zero percent of it was contained as of Saturday afternoon, forcing evacuations in Klamath County and shutting sections of a national forest, according to an update from the US Fire Service. Meanwhile, the agency said, it has no timeline available for the restart of the intertie lines.

Temperatures across California were forecast to remain high into Sunday, with Sacramento set to reach 42 degrees Celsius, before cooling down slightly on Monday.

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