As interest rises in pumped storage’s role for integrating variable renewable energy (VRE) resources into the grid, a key resource may be overlooked. Conventional hydropower can, and sometimes does, provide ancillary services that mimic pumped storage’s capabilities.
This report describes (1) the development and demonstration of an innovative, water-based methodology for analyzing and evaluating alternative energy and ancillary services operations under different market conditions, (2) the results from analyses using the methodology, and (3) recommendations based on results from the analyses. Results are provided from detailed analyses of a hypothetical three-unit hydropower plant operating (a) under cold weather (February) and hot weather (July) conditions; (b) with low, medium low, medium high, and high water budgets; and (c) in three market regions (CAISO, MISO, and NYISO). Across markets, seasons, and water budgets, the daily revenues from co-optimized energy, regulation, and spinning reserves significantly exceed the daily revenues from energy-only operation.
