USEA & EPRI: Thermal Energy Storage Repowering, A Pathway for Longer-Duration Energy Storage Deployment


In 2022, 12.6 GWe of coal capacity is planned to retire in the U.S., with this trend expected to continue through rest of the decade. While many of these plants were built before 1970, some retirements are being brought about due to criteria emission regulations, pressure to reduce CO2 emissions, and competition from low-cost renewable energy and natural gas fuel. Thermal energy storage (TES) is a potential repowering option that could harness the established grid connection to absorb excess renewable power for utilization at a later time period using the steam-Rankine cycle to deliver dispatchable capacity for durations in excess of 10 hours.

The goal of this workshop is to discuss the opportunities available to utilize the existing fossil fleet as energy storage systems. The workshop will explore a selected list of technologies that may be suitable for retrofit thermal application, identify key economic structures that will likely be needed to make thermal energy storage projects financially viable. The workshop will also provide a forum to discuss the anticipated performance, costs and benefits of reusing the fossil plants in this manner to deliver reliable power delivery with rapidly growing renewable energy generator penetration.