Water harvester cycles continuously without intervention

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 manual labour or a switching system, which adds complexity and cost.

By contrast, the new harvester developed at KAUST (King Abdullah University of Science and Technology) is said to passively alternate between the two stages so it can cycle continuously without intervention.

Project lead and KAUST post-doctoral student Kaijie Yang said initial inspiration came from observing natural processes, specifically how plants efficiently transport water from their roots to their leaves through specialised structures.

“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,” Yang said in a statement.

According to KAUST, the mass transport bridges are a collection of vertical microchannels filled with a salt solution that absorbs water.