Investigating the use of renewable energy sources in water production and water supply tanks as energy regulators on arid islands - The case of Syros

This diploma thesis examines the possibility of energy autonomy for the desalination system of the island of Syros through the utilization of renewable energy sources, specifically solar and wind energy. The aim of the study is to reduce dependence on fossil fuels, as well as to improve the environmental and economic efficiency of the water supply system. The work includes the conceptual modelling of Syros’ water supply system and the simulation of various energy supply and water management scenarios, with an emphasis on using water storage tanks to store desalinated water produced during periods of excess renewable energy generation. Different infrastructure combinations are examined, and for each case, the percentages of water deficit and shortage relative to the safety volume of the reservoirs, as well as the operating costs, are evaluated. The results indicate that the combination of existing renewable energy sources and water supply installations in Syros can cover over 96% of the annual potable water demand while reducing the operating cost of the system, and a slight increase in the number of installations can eliminate the water deficit and lead to full energy independence. The study proposes an innovative water supply model based on renewable energy sources, suitable for application in arid and non-interconnected Greek islands, aiming to achieve a sustainable, economical, and environmentally friendly solution.