Pumped storage hydropower (PSH) provides well-known benefits to securing a more reliable and sustainable renewable energy solution for the nation’s electrical power grid. In addition to serving as a quick-start, ready source of electricity during high-demand periods, PSH can store a vast amount of electricity and provides approximately 95% of utility-scale electrical energy storage in the United States.
Although demand for energy storage has increased along with expanding solar and wind power deployment, only 43 PSH facilities are currently operating in the United States, and only 1 new facility has come online in the past 20 years. To support the additional energy storage demands of the future, more PSH deployment is needed.
To find workable solutions that increase PSH project feasibility by reducing the costs, risks, and time associated with PSH facility development, the US Department of Energy’s (DOE’s) Water Power Technologies Office initiated a first-of-its kind challenge in 2019: the Furthering Advancements to Shorten Time (FAST) Commissioning for Pumped-Storage Hydropower Prize.
Before the start of the competition, researchers at DOE’s Oak Ridge National Laboratory (ORNL) led the development of a comprehensive technical analysis of PSH costs, risks, and timelines to define the current challenges. Key findings showed that civil works, including upper and lower reservoirs, water conveyances, transmission connection to the grid, and site preparation, accounted for approximately 67% of all PSH development costs. Equipment accounted for nearly 26% of these expenses, and engineering costs made up the remaining 7%.
Administered by the National Renewable Energy Laboratory, the prize attracted 22 individual and organizational contestants, who developed solutions that addressed these findings. ORNL then collaborated with Argonne National Laboratory and Pacific Northwest National Laboratory to support and counsel the contestants, culminating in four prize-winning concepts:
- Accelerating PSH Construction with Steel Dams – Gordon Wittmeyer, Southwest Research Institute
- Expected to lower current costs by one-third and reduce construction time by half
- Modular Closed-Loop Scalable Pump Storage Hydro – Tom Eldridge and Hector Medina, Liberty University
- May enable construction of 1–10 MW facilities without access to natural bodies of water
- Reducing PSH Excavation Duration, Cost, and Risk – Tracy Livingston
- Streamlines the excavation process to reduce excavation timelines by up to 50%
- Use of Modern TBMs for Underground Pumped Storage – Doug Spaulding, Nelson Energy and Golder Associates
- Proposes the use of tunnel-boring equipment to cut excavation times in half and reduce costs
The technical support phase of the prize has been completed, including ORNL’s collaboration with Liberty University under a cooperative research and development agreement (CRADA). The CRADA focused on further developing the proposed concept of the modular closed-loop facility by advancing the design and engineering using fluid-structure modeling.
These four proposed technology innovations have the potential to substantially lower current barriers to the continued growth of PSH. By refining and, in some cases, creating new hydropower processes, designs, and strategies, the FAST prize is poised to accelerate PSH development and address the country’s growing energy needs.
Final research and development products have been submitted to DOE for documentation and further consideration toward advancing these technologies.