From Laboratory to Field: Enhancing Solar Evaporation Performance through Advanced Thermal Management

Solar evaporation has emerged as a promising off-grid solution for producing potable water from diverse sources. With advanced modular designs, particularly downward evaporation and multistage configurations, remarkable efficiency improvements have been achieved. However, field implementations consistently exhibit notable performance degradation, sometimes as large as 57%, compared to laboratory benchmarks, presenting a major barrier to widespread adoption. Through comprehensive theoretical and experimental analysis, we identified that wind-induced convection and sky cooling, the environmental factors routinely overlooked in laboratory studies, substantially elevate heat losses and lower water productivity. Guided by heat and spectral analyses, we designed a spectrally selective airlock (SSAL) aerogel to mitigate these losses, resulting in a maximum 78% reduction in heat loss under realistic field conditions and five-fold increase in water productivity compared to aerogelfree modules. Field tests with seawater achieved 10.88 kg·m ^− 2 ·day ^− 1 yield, twice that of the aerogel-free counterpart, and the laboratory-field performance gap was reduced to only 2%. The analytical methodology and strategic framework presented in this work offers guidance for solar distillation optimization to enhance clean water accessibility for all while demonstrating broad applicability across diverse solar thermal applications.