Assessment of Photovoltaic-Hydraulic Hybridisation for Firm Power Supply
Juan A. Tejero-Gómez, Ángel A. Bayod-Rújula, Natalia Naval Department of Electrical Engineering E.I.N.A., Universidad de Zaragoza, Zaragoza, (Spain). 2026-06-27

Abstract

The fight against climate change requires replacing fossil fuels with clean, low-emission energy sources. Photovoltaic
technology has established itself as the most developed option among renewable energies; however, its intermittent and uncertain nature requires support systems to ensure supply stability. This paper presents simulations developed in MATLAB for the sizing of a hybrid system consisting of long-term hydraulic storage and photovoltaic generation with the capacity to provide a firm supply. The study addresses a configuration that has been little explored due to its limited current economic viability. The availability of suitable sites for hydraulic storage suggests that this could be a viable solution. The methodology is based on mathematical models integrated into an algorithm that represents the dynamic behaviour of the system, considering solar irradiance and temperature profiles. Through hourly simulations, the interaction between renewable generation and pumped storage is analysed in order to guarantee a stable supply under constant dispatch instructions at daily intervals. This study highlights the potential of converting solar photovoltaic energy into a dispatchable source, thus contributing to the transition to a cleaner and more reliable energy system.

Key words: Solar Photovoltaic, Pumped Hydro Storage, Renewable Energy Integration, Firm Power Supply, Optimal sizing.

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