Idaho Power Co.'s 20-year integrated resource plan lays out a path to closing down three coal plants by 2034 as the utility transitions to 100% clean energy by 2045.
The IDACORP Inc. subsidiary's resource plan, released July 1 and filed with regulators in Idaho and Oregon, forecasts a load growth of 1.2% annually for peak-hour demand as it prepares to serve 775,000 customers by 2038, up from 550,000. It lays out scenarios for exiting the Jim Bridger coal plant in Wyoming, of which Idaho Power owns one third, beginning in 2022.
Idaho Power in March announced its goal to transition to 100% clean energy by 2045, citing the lower costs of renewables compared to coal as well as its abundance of cheap hydroelectric power from 17 projects on the Snake River and tributaries.
"This plan shows the way forward as we work toward our goal of providing 100% clean energy by 2045," Tess Park, Idaho Power's vice president of power supply, said in a statement announcing the resource plan. "We see less coal, more solar and increased transmission capacity from the Northwest, while hydropower remains the backbone of our system."
According to the plan, 46% of the company's 3,658 MW of nameplate capacity, or 1,773 MW, is derived from hydropower. The portfolio also includes 1,118 MW of coal, 762 MW of natural gas and 5 MW of diesel. Its wind and solar resources come from purchased power, which constitutes 29% of its portfolio and also includes hydroelectric, geothermal and biomass products.
Under its preferred portfolio outlined in the resource plan, Idaho Power would add 822 MW of natural gas, 345 MW of solar, 60 MW of battery storage and 50 MW through demand response, and shed 1,026 MW of coal.
The company owns and operates 17 hydroelectric projects, three natural gas facilities, a diesel plant and shares ownership in three coal-fired facilities: half of the 522-MW North Valmy Station in Nevada; a 10% interest in the 585-MW Boardman plant in Oregon; and 770.5 MW from the 2,111-MW Jim Bridger plant.
Idaho Power plans to cease participation in unit 1 of Valmy by the end of this year and unit 2 no later than year-end of 2025. The company also plans to exit its share of the Boardman plant by the end of 2020 as a part of a regional-haze agreement.
As for the Jim Bridger plant, whose fate has been undefined, Idaho Power said it is working with regulators and majority owner Berkshire Hathaway Energy subsidiary PacifiCorp on early retirement plans. Under its preferred portfolio, Idaho Power would exit its interest in unit 1, or 177 MW, by 2022, and unit 2, or 174 MW, by 2026. Idaho Power's resource plan said its modeling "indicates removal of Jim Bridger units needs to be carefully evaluated because of potential heightened concerns about meeting regulating reserve requirements following their removal." Its modeling assumed a full exit from the remaining units, totaling 357 MW, by 2034.
"Guidance from the 2019 IRP indicates favorable economics associated with Idaho Power's exit from five of seven coal-fired generating units by the end of 2026, leaving only two units at the Jim Bridger facility operating into the 2030s," the resource plan said. "Idaho Power views this guidance as consistent with its long-term clean energy goals and expressed transition from coal-fired generation. The IRP's guidance further indicates favorable economics associated with pivoting towards an accelerated coal exit in future long-term resource planning if certain carbon policy is established."
The company is betting on solar as a reliable source of renewable power. It entered into a power purchase agreement with Alternative Power Development Northwest LLC subsidiary Jackpot Holdings LLC for the full output of the 120-MW Jackpot Solar (Twin Falls Solar) facility as well as the option to purchase the full output of the 100-MW Franklin Solar Facility(Twin Falls Solar), both located in southern Idaho. The company plans for the projects to come online in 2022 and 2023.
Critical to the achievement of its clean-power objectives is the development of the 300-mile, 500-kV Boardman-to-Hemingway transmission line between Idaho and Oregon. It is expected to come online in 2026 to connect the company with Pacific Northwest markets, improve reliability and help integrate renewables, Idaho Power said. PacifiCorp and the Bonneville Power Administration are other partners in the line.
On another major transmission project, construction began on a segment of The Gateway West transmission line will run 1,000 miles from a substation near Casper, Wyo., to a substation south of Boise, Idaho. PacifiCorp is leading the development of the multistage project, with Idaho Power.