Water and energy self-supply in isolated areas through renewable energies using hydrogen and water as a double storage system

Because of their geographical isolation, many areas depend mainly on imported fossil fuels for their water and energy production. In this context, the Canary Islands are one such remote area. Due to the topography of the islands, there are numerous isolated areas on each of the islands far from the major population centres. These are known as 'islands within islands'. The main aim of this paper is to determine the feasibility or otherwise of supplying from renewable energy sources both the energy and water needs of the 219 inhabitants of El Risco located in the municipality of Agaete on the island of Gran Canaria (Spain). For this purpose, the potential use of existing renewable resources in this isolated area has been analysed, using hydrogen as energy vector. A reverse osmosis (RO) plant is integrated into the system to ensure water self-sufficiency and, in turn, constitutes a double storage system (hydrogen-water). Based on the results obtained from the study, the technical feasibility of the system is confirmed, with an annual energy production of 1,743,031 kWh/year compared to a consumption of 672,314.32 kWh/year, as well as a potable water production volume of 46,546.80 m3/year obtained from the RO plant. The reliability of the system is confirmed in the economic analysis, obtaining a renewable electricity cost of 0.107 €/kWh compared to 0.18 €/kWh when using conventional electricity.