Pumped Storage Hydropower (PSH) is one of the most cost-effective utility-scale options for grid energy storage. The U.S. has plants across the country, totalling over 20GW of capacity. Now the Dept of Energy (DoE) is backing four teams developing blue sky (water?!) ideas that should make the next generation of PSH even cheaper. In this article the National Renewable Energy Laboratory (NREL) tracks their progress so far. They include dams made of steel, tunnel-boring machines for underground PSH, engineering innovations (to reduce tunnel construction times, costs, risks), and 1-10 MW modular “closed-loop” plants (using big water tanks, no need for natural reservoirs). They’re still at the design stage but the DoE’s support is there to reduce commissioning time from 10 years to 5. The cheaper and more flexible PSH becomes the more solar and wind can store its excess generation for a clean energy grid.
Energy Post 28th Feb 2020 read more »