Techno-economic assessment of a novel wind-powered RO system with a compressed air energy storage for water desalination

Abstract

The convergence of renewable energy and water desalination offers a promising solution to water scarcity and climate change. Utilizing wind power to operate reverse osmosis (RO) systems promises a sustainable future with ample freshwater and reduced carbon emissions. This paper introduces a novel wind-powered RO desalination system, employing a pneumatic approach with wind-driven compressors, energy storage, and air-operated pumps. Additionally, an energy recovery pressure exchanger enhances efficiency by capturing energy from the brine. A detailed mathematical model using MATLAB/Simulink evaluates system performance across various Egyptian coastal locations, optimizing wind turbine numbers to minimize desalination costs. The findings reveal that compressed air energy storage is essential for consistent operation despite wind variability, ensuring reliability during low or fluctuating wind conditions. The techno-economic assessment highlights the importance of site-specific adaptations for maximizing performance and cost-effectiveness. Hurghada emerged as the optimal location with the lowest desalination cost ($0.65/m³) and highest annual water production (19,500 m³), while Suez had the highest cost at $1.35/m³. Seasonal variations impact performance, with mid-winter showing more system on-off cycles compared to mid-summer. Sensitivity analysis highlights the importance of optimizing capital and operational costs, as a 20 % variation in these costs shifts the levelized cost of water by 10 %.