Plucking water from the air

29 July, 2024

A new solar-powered system efficiently extracts moisture from the air, offering a sustainable solution for irrigation.

Even in arid parts of the world, there is usually moisture in the air. This moisture could provide much-needed water for drinking and irrigation, but extracting water out of air is difficult. A new technology developed by KAUST researchers can consistently extract liters of water out of thin air each day without needing regular manual maintenance.

Harvesting water from air is not a new idea, or even a new technology, but existing solar-powered systems are clunky.

Solar-powered harvesters work in a two-stage cycle. An absorbent material first captures water from the air, and once it is saturated, the system is sealed and heated with sunlight to extract the captured water. Alternating between the two stages requires either manual labor or a switching system, which adds complexity and cost. The new harvester developed at KAUST requires neither — it passively alternates between the two stages so it can cycle continuously without intervention.

“Our initial inspiration came from observing natural processes: specifically how plants efficiently transport water from their roots to their leaves through specialized structures,” says postdoc Kaijie Yang, who led the study.

This gave the team the key idea for their new system. “In our system, mass transport bridges play a crucial role as a connection between the ‘open part’ for atmospheric water capture and the ‘closed part’ for freshwater generation,” explains Yang.

Read more at KAUST Discovery.