Feasibility of atmospheric water harvesting and generation technologies: Bridging innovation and market adoption

Atmospheric water harvesting and generation (AWH-AWG) technologies constitute an emerging class of decentralized water supply systems, with the potential to complement or substitute conventional surface and groundwater sources. This article presents a critical and integrated assessment of AWH-AWG technologies based on a PRISMA-guided systematic screening of 133 peer-reviewed studies, including 22 review articles published between 2020 and 2025, complemented by patent analysis and a survey of commercially available systems. Analysis of passive sorption-based approaches highlights hydrogel materials as the class exhibiting the highest water uptake performance, with particular emphasis on LiCl@PHEA, which has been reported in the literature to achieve a water uptake of 11.18 g g^-1 at 90 % relative humidity (RH). Among MOF-based sorbents, the maximum reported water uptake reaches 1.95 g g^-1 at 75 % RH for Cr-soc-MOF-1, whereas superior performance under low-humidity conditions is observed for bimetallic MOF-74, achieving 0.40 g g^-1 at 10 % RH. In comparison, active methods demonstrate that vapor compression refrigeration cycle (VCRC) systems achieve the highest water generation rates among currently available technologies, with reported generation capacities of up to 42 L day^-1. The results emphasize that AWH-AWG technologies still lack robust pilot-scale demonstrations under representative climatic conditions. Explicit consideration of associated costs, employed energy sources, and assessment of scalability at the community scale remain necessary. With respect to passive approaches, the coupling between material performance and material cost emerges as a critical limitation, as high-performing sorbents may present prohibitive costs for decision-making and deployment. Equally important, climatic suitability constitutes a fundamental prerequisite for bridging the gap between laboratory-scale feasibility and the realization of reliable atmospheric water supply in practical applications.