‘Energy towers’–an analytical model of power generation by evaporative cooling in hot, dry air areas

This study presents an analytical model for Energy Towers, a renewable energy technology that utilises evaporative cooling to generate power. In hot and dry regions, water is sprayed at the top of the tower, creating a downdraft as the droplets evaporate. This downdraft drives turbines at the base, producing energy. The model simplifies the system by using averaged values without accounting for temporal or horizontal variations to evaluate its feasibility. Net power output is determined by balancing the energy generated by the downdraft and the energy required for pumping water. Simulations indicate that net power scales approximately with the fourth power of tower height, with optimal operation achieving around two-thirds of the total output due to unavoidable losses. Additionally, Energy Towers have a significantly smaller land footprint compared to photovoltaic panels or wind turbines, requiring only one-tenth of the area, making them an efficient and space-saving renewable energy solution.