Pumped-Storage Hydropower Plants: The New Generation

This chapter describes some current trends and future challenges related to pumped-hydro energy storage (PHES) with special emphasis on the mechanical aspects of hydraulic machinery, power electronics devices used for variable speed operation, and utilities’ operation strategies. After a brief introduction and historical background, the new generation of PHES is presented with particular focus on those equipped with variable speed technology. Typical configurations of pumped-storage hydropower plants (PSHPs) are also briefly described. The next section focuses on reversible pump-turbines, discussing their operating limits and presenting the state-of-the-art of the research on their unstable behavior. The operating principle and some basic aspects of the electrical machines most widely used in PSHPs are next described. Power electronics devices typically used in PSHPs for variable speed operation are described in detail, along with some recent developments on variable speed drives. Finally, utilities’ operation strategies are reviewed in detail, and some future challenges to make the best possible use of PHES assets according to their new role are identified.