Techno-economic analysis of a solar-powered humidification-dehumidification desalination system under fogging effect

Abstract

Different techniques are utilized to overcome the problem of freshwater shortage around the world. Humidification-dehumidification technology is among the promising methods, especially when powered by cost-effective solar energy sources or when used in remote desert areas with abundant solar resources. In this study, a solar energy-powered humidification-dehumidification system is assembled and tested. Two solar energy systems are supplying the humidification-dehumidification system with heat and electricity, namely an evacuated tube solar collector and an array of photovoltaic panels, respectively. The studied system utilizes three fogging nozzles, each with a 10-µm diameter, that allow efficient energy conversion. Also, the system was tested under the influence of a single nozzle with a larger diameter for comparison purposes. The fogging technique reduced the power consumption while boosting the total system productivity. The system was able to achieve a maximum gained output ratio of 4.4 at saline water and air temperatures of 80 and 53.44 °C, respectively. The rate of freshwater production ranged between 1.7 and 3.85 L/h. At the highest tested saline water to air ratio, the system with three 10-µm nozzles enhanced the gained output ratio by 23.68 and 67.33 %, compared to the single nozzle configuration with 20 and 30-µm diameter, respectively. An economic evaluation showed a best-averaged price of 0.0543 USD/L of freshwater.