Energy arbitrage in PV-PHS systems

In this paper, we use MHOGA software for the evaluation of adding pumped hydro storage (PHS) for energy arbitrage in utility-scale PV generating systems. PHS is used for electricity price arbitrage, pumping water from the lower reservoir to the upper reservoir with the PV generation during hours of low electricity price and generating electricity by means of the stored water with the turbine during hours of high price (during these hours the PV generator also injects its production to the grid). The control strategy creates setpoints for the use of the pump and the turbine, trying to obtain the maximum benefits from the electricity sold to the grid, maximizing the net present value (NPV). An example of application is shown, obtaining conclusions about the economical viability of the PV-PHS system compared to the PV-only system: in the case studied in this work, it is not worth to add PHS to the PV system.