Towards real-weather water-production practice for solar-driven reverse distillation: Effects of ambient temperature and solar radiation

Solar-driven reverse distillation has recently exhibited promising water-production performance and significant potential for practical application. However, related experimental comparison and wide-range evaluation under different real-weather conditions are scarce with the effect mechanism and quantitative relationship remaining unclear among ambient factors and water-production efficiency, hindering further performance optimization and industrial application of solar-driven reverse distillation. This research explores the underlying mechanism of how ambient temperature and solar irradiance influence the efficiency of solar-driven reverse distillation, and quantifies the relationship among these ambient factors and efficiency under real-weather conditions. Theoretical analysis based on heat-and-mass transfer principles reveals that the increased ambient temperature reduces heat-transfer loss and higher solar radiation promotes the evaporation heat flux density, both increasing the efficiency. We then conducted 19 days of outdoor experiments, obtaining daily and hourly data of ambient temperature, solar irradiance, and distillate mass. Statistical analysis of the experimental results has demonstrated the ambient temperature and solar irradiance have significant impact on the efficiency. By further discussing the coupled impact of ambient factors, we obtained the quantitative relationship among the efficiency (η, %), ambient temperature (T_amb, °C), and solar irradiance (q_in, W·m⁻²) as η = 12.2 + 0.63T_amb + 0.02q_in (6 < T_amb < 38, 541 < q_in < 866) from the daily experimental data, and η = 11 + 0.55T_amb + 0.028q_in (5 < T_amb < 41, 285 < q_in < 924) from the hourly data. This research provides straightforward pathways to predict the outdoor water-production performance of solar-driven reverse distillation with meteorological data, promoting its progress towards real-weather water-production practice.