SALT LAKE CITY, Oct. 14, 2021—PacifiCorp, through its Rocky Mountain Power division, will consider the feasibility of a pumped hydroelectric storage project located in Mud Lake and Dry Canyon, immediately north of Bear Lake in Idaho. The project as envisioned could provide up to 1,800 megawatts of significant long duration energy storage (up to 16 hours) for peak customer demand and renewable energy integration to reliably serve PacifiCorp’s 2 million customers across six western states.
The preliminary permit application filed today with the Federal Energy Regulatory Commission—together with 10 other preliminary permit applications—give the company the opportunity to further evaluate the project sites for possible development in states served by PacifiCorp. These permits do not authorize construction. Rather, they allow the company to preserve priority for a future license application if the engineering, economic and other analyses of the individual sites show the projects can benefit customers.
“Our long-range planning for customer needs anticipates that significant investment in energy storage resources will be in the best interests of PacifiCorp customers in coming years,” said Mark Sturtevant, Vice President, Renewable Resources. “It’s important that we begin evaluating these sites to determine if they could bring the substantial benefits of clean energy supply and enhanced system reliability to our customers. Energy storage resources are needed to fill an increasing role in grid modernization to integrate and optimize the dramatic increase in renewable energy resources that serve customers. Pumped hydroelectric storage has distinct advantages, including longer plant lives and significantly greater energy delivery capability compared with chemical batteries. This makes feasibility studies of these sites an important part of prudent utility planning.”
The Idaho project would include construction of a storage reservoir in Mud Lake, together with an upper reservoir in Dry Canyon, immediately east above Mud Lake. Intake works, piping and much of the electric facilities would be constructed underground. Benefits of the project include additional flexibility to maintain water storage reserves in Bear Lake at a higher level, further supporting recreational and other beneficial uses, plus the ability to further improve the quality of water diverted into Bear lake for later irrigation use.
The project would use PacifiCorp’s longstanding water rights to divert and store Bear River water in Bear Lake for both irrigation and power generation purposes. No new water right would be needed, although water right change applications would be filed in Idaho and Utah to modify conditions of existing rights by adding a new place of beneficial use, a potential new point of diversion in Mud Lake, and providing water storage rights in Dry Canyon.
The other sites for which PacifiCorp is seeking preliminary permits include four in Utah, three in Wyoming, two in Oregon and one in Washington, all of which are accessible by PacifiCorp’s multi-state transmission network and will be reviewed for feasibility.
The Federal Energy Regulatory Commission Preliminary Permits are issued for up to four years and require the company to submit periodic reports on the status of its studies.