Pumped Storage Hydro

Washington university studying pumped storage hydropower siting

Washington university studying pumped storage hydropower siting

The Washington State University (WSU) Energy Program is conducting an information study related to pumped storage hydropower (PSH) siting.

Identifying and understanding the issues and interests surrounding the siting of PSH in Washington State is needed if this proven technology is to be used to help achieve the state’s commitment to limit greenhouse gas emissions, transition off fossil fuels and reduce the impacts of climate change, the university said.

The state is committed to achieving an electricity supply free of GHG emissions by 2045, aiming to stem climate change and improve the health of communities while creating family-sustaining jobs. More is needed than just replacing fossil fuel sources with carbon-free renewables such as solar and wind. Energy storage technologies ensure that there are no disruptions in supply with the use of renewable resources. While the use of different energy storage methods and technological advancements are increasing rapidly, one of the most established, reliable and proven methods, dating back decades, is PSH.

PSH can provide energy at times when solar and wind resources fluctuate. PSH is a mature and proven long-duration storage technology that can provide more hours of electricity than most other storage methods. As of 2022, PSH provided about 96% of the energy storage capacity in the U.S. Its mechanical process is mechanical does not rely on mined minerals such as lithium. And PSH’s lifecycle costs are lower than most other battery technologies due to its long lifespan.

Siting needs include specific geology and a sufficient elevation difference between the reservoirs, often between 1000 and 2000 feet. Barriers to developing PSH include its high construction expense and a long construction time. Of particular interest to WSU’s information study is the fact that there are possible siting impacts to resources, including land use, environmental and Tribal cultural resources.

The WSU study focuses on closed-loop PSH, where neither reservoir is connected to an existing water body. Closed-loop PSH has fewer impacts to wildlife, habitats and the hydrologic cycle than open loop PSH.

The information study was written into the Washington State Legislature 2023 Engrossed Second Substitute House Bill 1216 (Section 306), concerning clean energy siting, and signed into law May 3, 2023 effective July 23, 2023. The legislature directs WSU to conduct a process to identify issues and interests related to siting pumped storage projects in Washington State in order to support expanded capacity to store intermittently produced renewable energy.

WSU said listening to as many people as possible is key to identifying and understanding issues, interests and concerns regarding PSH siting. WSU has assembled a PSH Study Team consisting of the WSU Energy Program study lead, the WSU Tribal Liaison for Special Projects, facilitation and outreach professionals from Ross Strategic, and a geographic information system (GIS) consultant from Meridian Environmental.

A state-wide online public meeting will take place Sept. 11, 2024. The WSU Energy Program said this is the first meeting of a series of PSH siting topics and will provide a deeper look into basics, including considerations of closed-loop and open-loop systems, and a talk and discussion on Tribal and natural resources.

Two to three more meetings will be held during fall and early winter of 2024 to address other siting issues and provide more opportunities for interest parties to communicate their thoughts, considerations and ideas about these issues. Separate forums specifically for Tribal leaders, members and staff are also being planned.