Solar-Powered Desalination as a Sustainable Long-Term Solution for the Water Scarcity Problem: Case Studies in Portugal

Abstract

The challenge of global water scarcity, exacerbated by population growth, pollution, and uneven resource distribution, demands innovative solutions. Seawater desalination, particularly Reverse Osmosis (RO) desalination technology, offers a promising remedy due to its efficiency, economic attractiveness, and enduring durability. This study explores the potential of solar-powered desalination to replace grid-imported electricity as a cost-effective solution to water scarcity, emphasizing economic and environmental aspects. We delve into the economic viability of desalination by developing a model that considers desalination capacity, input electricity prices, and specific energy consumption. Applying this model to case studies in Portugal (Porto Santo Island in the Madeira Archipelago and Algarve in the southern mainland) demonstrates that integrating photovoltaic (PV) solar energy systems to supply the electricity required in the desalination process can reduce the unit production costs of desalinated water by about 33%. The obtained unit production cost of desalinated water using solar PV input is lower than current water tariffs, underscoring the economic feasibility of this approach. The proposed solution is in line with the United Nations Sustainable Development Goals (SDGs), contributing to Goal 6 (Clean Water and Sanitation), Goal 7 (Affordable and Clean Energy), and Goal 8 (Decent Work and Economic Growth).