Optimal design for floating solar still by structural modification: A review

Abstract

Floating solar distillation is a newly emerging and sustainable technology for producing clean water. However, recent outdoor tests of the floating solar still produced lower freshwater yield than expected, suggesting the needs for structural improvement. This review focuses on the latest structural modifications of the floating solar still as well as their impact on water production. Firstly, recent improvements on evaporation and water pathway structure to enhance the interfacial evaporation include the effective salt discharge and water transportation. Secondly, the multi-effect design has showed advantages in heat recovery of floating solar still and increasing yielding performance, albeit at a higher cost due to the increased complexity. Thirdly, shape of condensation cover influences vapor condensation and freshwater collection, with centrally symmetrical shapes and super-hydrophobic condensation surfaces being recommended. Fourthly, the stability of a floating solar still is vital for smooth yielding process, yet is under-explored due to the complex dynamics in marine environment. Lastly, floating solar stills with different structures were discussed regarding potential improvements and optimization strategies. This review study aims to offer valuable insights into the development of floating solar still with the optimal structures, promoting their practical applications and encouraging further exploitation of other potential uses.