Pumped storage hydro project at Seminoe Reservoir would significantly improve value of Wyoming wind energy and transmission
300-700 megawatt energy storage project using Seminoe Reservoir is located near
most of the proposed wind development in Wyoming
Gridflex Energy, LLC – a developer of pumped storage hydropower projects providing support to renewable energy – has focused on a site in southern Wyoming as one of the best in the country. Seminoe Pumped Storage, proposed to be developed in phases of 400 and 300 megwatts each, for a total of 700 megawatts (MW), would pair new upper reservoirs with Seminoe Reservoir as the lower reservoir to create an energy storage plant ideally matched to the Wyoming wind energy resource.
The project site is located just 30 miles from both the planned originating terminal of the Transwest Express DC line and Rocky Mountain Power's Aeolus substation. Transwest Express would deliver up to 3,000 megawatts of wind energy from the Chokecherry and Sierra Madre project, and Pacificorp recently issued a request for proposals for more than 1,200 megawatts of new wind energy – the majority of which would come from eastern Wyoming and use the new Gateway transmission system.
Gridflex has been considering the Seminoe site for a number of years, but the timing for advancing the Seminoe Pumped Storage is now ideal due to the strong market interest in Wyoming wind and progress in new transmission to western markets. While the strong winds have high productivity, they are variable and intermittent. Additionally, wind energy alone would also make relatively inefficient use of new transmission. Based on studies that Gridflex has done using hourly Wyoming wind data, Gridflex asserts that Seminoe Pumped Storage would help significantly to "firm up wind with wind," creating a more reliable resource, as well as create considerable savings on new transmission through more efficient use. Pairing Wyoming wind with Seminoe Pumped Storage could also help Pacificorp reduce its reliance on coal, which has been a concern of regulators in states like Oregon.
Gridflex noted that Seminoe Pumped Storage has long been recognized as the best pumped storage prospect in Wyoming, and ranked highly in Pacificorp's 2017 Integrated Resource Plan when compared with other regional pumped storage options. Project value is estimated at approximately $1.6 billion for full build-out of the project, which Gridflex anticipates could be on line by 2026.
Pumped storage hydropower is the best-established form of bulk energy storage, with costs far lower than batteries and useful lives greater than 60 years – four to five times that of utility-scale batteries.
-- Gridflex Energy can be reached at (208) 246-9925 or by email at [email protected] --