The Bootleg fire in southern Oregon has shut down power lines that carry electricity from the Pacific Northwest to California, leaving the Golden State without a major power source during an intense heat wave that was already straining the grid.
The affected power lines, the California-Oregon AC interconnection, can carry about 4,800 megawatts of power, enough electricity to serve millions of homes. It is an important source of electricity for California in the summer and is used to send energy north during periods of high demand here in the winter.
The supply problem prompted California grid operators for the second day in a row to issue an urgent warning to customers across the state to conserve power between 4 p.m. and 9 p.m. to prevent advancing power outages.
The interie is administered by the Bonneville Power Administration, the Portland-based federal energy marketing agency that sells electricity from federal hydroelectric plants and operates three-quarters of the region’s high-voltage grid. Steve Wingert, a BPA spokesperson, said the Klamath County Bootleg fire, which doubled in size overnight, was burning in or near the rights-of-way for the transmission lines.
While the power lines sit on large steel towers and generally escape all damage except the largest fires, heavy smoke and particulate matter can cause them to spark and go offline.
“The lines have been in and out of service and we ended up taking them out of service for the stability of the system,” Wingert said.
He said line personnel are in the area to monitor the status of the fire and the proximity of equipment. They are in contact with coordinators awaiting approval to test and return the lines to service. While the capacity of the lines is 4,800 megawatts, BPA has set that limit at 428 megawatts. One megawatt of electricity can power about 400 to 900 households.
The intertie, which also includes lines owned by Portland General Electric and PacifiCorp, was taken off the air shortly after 1 p.m. Saturday. Wingert said the operational status of the lines is not expected to affect utilities in Oregon.
The California grid operator, dubbed the Independent System Operator, already faced challenging conditions amid triple-digit temperatures across much of the state on Friday. The flex warning asks customers to set their thermostats to 78 degrees and avoid using large appliances to reduce the load on the grid. The grid operator expects peak demand of just over 40,000 megawatts and an available capacity of 46,000 megawatts.
With the disappearance of the intertie, the situation became more precarious. California Governor Gavin Newsom has issued an emergency proclamation allowing commercial and industrial users to use their backup power sources, reducing energy consumption in ports and freeing up other more polluting energy sources that are typically left offline, such as diesel generators and inefficient natural gas-fired plants.
“Even with all that, we’re probably going to fall short and we should see some occasional issues with the offerings and coverage you deserve and ask for,” Newsom said at a news conference.
Elliot Mainzer, the chief executive of the California grid operator and the former administrator of Bonneville, told reporters it was going to be a “stressed evening on the network.”
“We are urging everyone in California to do everything they can,” Mainzer was quoted as saying in The Sacramento Bee.
— Ted Sickinger; [email protected]; 503-221-8505; @tedsickinger