Possibility of Seawater Desalination Using Reverse Osmosis Powered by Solar Photovoltaic Electricity on the Island of Crete, Greece

Water demand is rising globally, while water availability is declining due to factors such as pollution, climate change, and inefficient management. Among emerging clean water technologies, reverse osmosis stands out as a widely adopted, though energy-intensive, method. The island of Crete, Greece, hosts a thriving tourism industry that consumes substantial quantities of water. In regions with limited water resources, such as the Eastern Mediterranean, seawater desalination using reverse osmosis is expanding rapidly. This method is already broadly implemented in Mediterranean countries including Cyprus, Malta, Spain, and Israel. On Crete, seawater desalination via reverse osmosis can help increase potable water availability, with the required electricity supplied by solar photovoltaic (PV) systems. This study estimates that powering reverse osmosis plants to meet 20% of Crete’s annual potable water demand would require solar PV systems with a total installed capacity of 76.56 MWp, at an estimated installation cost of €84.22 million. The required system size is relatively modest, and the investment cost is considered affordable. This work may be of interest to policymakers, municipal authorities, water management agencies, and hotel operators, who all have a stake in securing sustainable water supplies for the island.