A California power plant is likely to shut down for the first time ever due to low water levels during a prolonged drought, which is squeezing the state’s very scarce electricity supplies, state officials said yesterday.
The Edward Hyatt Power Plant, an underground facility adjacent to the Oroville Dam in Butte County, is expected to close in August or September, said John Yarbrough, deputy director of the California Department of Water Resources for the State Water Project. The plant has been in continuous operation since it opened in 1967. It receives water from Lake Oroville, and that reservoir has sunk due to the drought, CNN previously reported.
Lake Oroville is one of several California reservoirs affected by drought.
In addition, “high heat events in California and the rest of the West have started earlier than usual and exceeded historical temperature levels,” California Energy Commission and California Public Utilities Commission leaders said in a July 1 letter to the California Independent System Operator (CAISO), the network manager.
The country’s electricity system expects that around 1,000 megawatts of electricity generation will be lost as a result. While this is only a fraction of a system with a peak daily demand of 44,000 MW, supplies are already scarce, said Lindsay Buckley, a spokeswoman for California’s Energy Commission.
“Based on our May forecasts, we really didn’t have 1,000 megawatts to lose,” Buckley said in an interview. “So that’s what we’re dealing with now” in relation to the state’s hydropower resources.
The drought in the Golden State is linked to warming and is one of the many effects climate change has on the state and its electricity supply, according to climate scientists. California is also grappling with the effects of forest fires and extreme heat. State officials believe that in order to keep the lights on this summer, they will partly rely on residents to throttle their electricity usage during peak hours, such as 4:00 p.m. to 9:00 p.m. local time.
“The climate impact is coming hard and fast,” said Buckley. “We need all hands on deck, and that includes the normal Californians and they just help save money in these times.”
Last weekend, California narrowly avoided power outages when the smoke from the Oregon Bootleg Fire, which acted as an electrical conductor, shorted power lines feeding the Bonneville Power Administration’s California-Oregon Intertie transmission network (Power wire, 15th of July). The grid lost an estimated 5,500 MW of electricity flow, which corresponds to about 10 large power plants.
California Governor Gavin Newsom (D) passed an executive order on Saturday that temporarily lifts some environmental restrictions on natural gas-powered power plants, one of several measures to free up electricity. Newsom announced yesterday that it is sending more fire-fighting resources to Oregon to help fight the bootleg fire and new fires.
The state grid operator said it wanted to buy additional power capacity that would be available this summer.
It “made no commitment to find a specific number of MWs as we will consider evolving conditions over the course of the summer,” CAISO spokeswoman Anne Gonzales said in an email. The grid manager obtains bids in an open market and then determines “the resources to be available to the system for a major event, taking into account the most current information, including current load forecasts, the potential west-wide” extreme heat events and low hydropower conditions. ”
CAISOs Summer Assessment Report identified late summer as the period with the greatest risk for an adequate electricity supply from hydropower. The conditions studied assumed a significant drought, Gonzales said.
“To address the forecast of low hydropower conditions and possible extreme heat events this summer, we recently used our capacity procurement mechanism to bring more energy to our market in the late afternoon / evening when the grid is most at risk of congestion,” she said . “We monitor the hydropower conditions and storage levels very closely and coordinate with the state and the plant operators.”
Meanwhile, the drought has hit Lake Powell, an artificial reservoir on the Colorado River in Utah and Arizona. The Bureau of Reclamation plans to release water into Lake Powell to keep it from sinking below the levels required for hydroelectric power generation, NPR reporter Luke Runyon tweeted yesterday.
Release occurs when the reservoir drops below 3.525 feet. The water would come from the Blue Mesa, Flaming Gorge and Navajo reservoirs, as set out in a Drought Response Operations Agreement to protect Lake Powell, Reclamation spokeswoman Becki Bryant said in an email.
Reclamation plans to release its July 2021 operations plan for the Colorado River System reservoirs today, which will include a 24 month study and further information on planned water releases.
Droughts in the western states affect each other, Buckley said.
“Other states see cuts in theirs [electricity generation] Capacity, ”said Buckley. “We rely on each other” in the electricity import-export market.
The power outage at the Hyatt plant would occur if lake levels dropped to around 630-640 feet due to a lack of water to turn the plant’s hydropower turbines, said Yarbrough of California DWR.
Lake Oroville is currently at 666 feet with 1,015 million acres of water storage, representing 29% of its total capacity and 37% of its historical average. In the past week, the reservoir has dropped from 673 to 666 feet, he said.
Hyatt is rated for an output of up to 750 MW, but typically produces between 100 and 400 MW depending on lake level, Buckley said. The state of DWR expects the plant to generate around 20% of the previous year’s output this year.
The Thermalito power plant downstream of the Oroville Dam will continue to operate at a minimal level, Yarbrough said.
Environmental laws limit how much water can be released from the system into reservoirs. Water discharges into the Feather River are required for water supply, environmental, and fishing needs; for health and safety; and to prevent salinity ingress, Yarbrough said.
Reprinted from E&E News with permission from POLITICO, LLC. Copyright 2021. E&E News provides important news for energy and environmental professionals.