Solar humidification and dehumidification system: integrating ultrasonic atomizer and solar still state-of-art

• The combination of solar still , solar humidifier, and ultrasonic atomizer is recommended. • Maximum freshwater production of 13.38 L per day is achieved. • Maximum GOR of 0.57 is achieved. By 2050, global desalination capacity is expected to reach 192 million m 3 /day which is twice the current capacity. This expectation is due to the increase in demand from increasing population, industrial activities and urbanization. The potential of solar energy in arid regions fosters the application of solar thermal desalination systems. The novelty of this study is highlighted by harnessing direct solar energy within the humidifier unit and utilizing forced convection to enhance evaporation. Unlike convention solar humidification and dehumidification (HDH) systems, the presented system operates capturing direct solar energy, coupled with ultrasonic atomization of droplets, and its solar still state-of-art design. The humidification process is driven via two primary mechanisms, natural convection and evaporation of atomized droplets capturing direct solar energy. The dehumidification process is achieved through direct contact condensation. This solar HDH systems operating in the closed-loop operation produces a daily freshwater yield of 10.2 L on average with 6 h of operation. The maximum GOR achieved is 0.57. Findings of this study indicate that coupling ultrasonic atomizer within a direct solar humidifier and its hybrid solar still design enhances humidification process, increases efficiency endorsing dual freshwater production channels, and implementation of this technology suitable for regions with abundant solar energy.