Modelling and operational analysis of reversible hydroelectric solutions in island electricity systems: The case of Gran Canaria

Abstract

The island of Gran Canaria, with an annual energy demand of 3327,872.76 MWh, has completely isolated electricity system and is still highly dependent on fossil fuels, despite the progressive increase in the implementation of renewable energies, which in 2023 reached a coverage of 23%. The inherent variability in renewable sources requires large scale energy storage solutions to guarantee the stability of the electricity system and move towards its total decarbonization. This research covers two new energies proposals in Gran Canaria for reversible hydroelectric use for mass energy storage and their comparative analysis with the configuration currently proposed and under construction, and whose completion and commissioning is planned for 2030, the pumped-storage hydroelectric power plant “Chira-Soria” [Ch-S], with a capacity of 200 MW in turbined and 220 MW in pumped storage. The two proposals under investigation are: (a) an integrated solution connecting the Chira and Cueva de Las Niñas dams to achieve with such a connection as a larger upper reservoir, keeping Soria as a lower reservoir [(Ch + CN)-S]; and (b) the synchronized operation of two independent reversible hydropower plants: the existing Chira-Soria (Ch-S) and a new proposal called Cueva de Las Niñas-Soria (CN-S), forming the system [(Ch-S) + (CN-S)]. The objective is to address the technical, energy, environmental and economic performance of the three configurations through simulations and integration in the real system in 2023, hydraulic-energy analyses and climate impact estimates. The study also considers the ability of these infrastructures to integrate higher renewable penetration, provide critical grid services such as frequency regulation and reserve power and improve the resilience of the island electricity system. The results indicate that the third option [(Ch-S) + (CN-S)] achieves full decarbonization of the Gran Canaria electricity system, although it requires higher levels of investment and significantly more installed renewable power. This strategy represents a technically feasible solution for achieving a fully decarbonized and autonomous energy system under the evaluated conditions for the island.