Modeling and Simulation of Advanced Pumped-Storage Hydropower Technologies and their Contributions to the Power System

With the larger penetration of variable renewable energy resources, the role of energy storage in the power system is becoming increasingly important. The flexibility of operation of hydro and pumped-storage power plants and the variety of ancillary services that they provide to the grid enable better utilization of variable renewable resources and more efficient and reliable operation of the entire power system. The U.S. Department of Energy’s Water Power Program has funded a recent study to enhance the modeling and simulation of advanced pumped-storage hydropower (PSH) technologies and examine the value of different services and contributions that they can provide to the power system. The technical approach consisted of two main components: (1) advanced technology modeling and (2) detailed production cost and revenue simulations. The advanced technology modeling focused on the development of dynamic simulation models for advanced PSH technologies, such as adjustable-speed (AS) and ternary units. These new models were developed as vendor-neutral models and published during the course of the project. The production cost and revenue simulations focused on the Western Interconnection (WI). The analyses were performed for the entire WI, for the California electricity market, and for a single balancing authority, the Sacramento Municipal Utility District. The goal of the study was to provide a comprehensive evaluation of PSH plants and their contributions to the power system. The project team has used several computer tools, including the PSSE, FESTIV, CHEERS, and PLEXOS models, to simulate system operation and contributions of PSH plants. Advanced PSH technologies, i.e., AS and ternary units, were also modeled. Detailed modeling and simulation studies were performed using different time steps ranging from a fraction of a second to one hour. This paper provides an overview of the simulations performed during the study and some key results of the analyses.