A comprehensive review of advancements in solar and waste Heat-Based air Humidification-Dehumidification desalination

Abstract

Freshwater and energy are essential for human progress, but both are under growing pressure due to increasing populations and urbanization. Seawater desalination has emerged as a promising solution to water scarcity, yet traditional methods rely heavily on fossil fuels, raising environmental concerns such as global warming. In response, researchers are focusing on renewable energy-based desalination methods to develop sustainable alternatives. The humidification-dehumidification (HD) process is particularly notable for its low energy consumption and compatibility with renewable energy sources like solar or low-grade waste heat, reducing dependence on electricity. The main findings from the review indicate that HD desalination systems are increasingly optimized by integrating renewable energy sources like solar power and low-grade waste heat, improving both efficiency and sustainability. A key trend is the development of hybrid systems that combine HD desalination with energy generation technologies such as photovoltaic thermal collectors and organic Rankine cycles, addressing water and energy needs simultaneously. However, challenges remain in scaling these systems for broader applications, particularly in cost-effectiveness and maximizing freshwater production in diverse environments.