A hydro storage power plant is a hydro power plant that uses the available hydro energy of a stationary water storage.
Editor note:
The distinction between a run of river power plant and a hydro storage power plant is important for modelling, but in reality not so easy. The chosen distinction follows the document: European Network of Transmission System Operators for Electricity (ENTSO-E): Hydropower modelling – New database complementing PECD, V.1.0, 12 December 2019, https://www.entsoe.eu/Documents/SDC%20documents/MAF/2019/Hydropower_Modelling_New_database_and_methodology.pdf