This New Solar tech Extracts 3 Liters Of Water From Thin Air Daily

A team of researchers at King Abdullah University of Science and Technology (KAUST) has developed an innovative atmospheric water extraction system that reliably produces liters of freshwater daily with minimal maintenance.

This advanced system is a refined version of the solar-driven atmospheric water extraction (SAWE) method, designed to generate freshwater continuously when exposed to sunlight. By enhancing material movement and energy efficiency, the system can yield 0.65 liters of freshwater per square meter per hour under typical sunlight and 90% humidity. Notably, it remains effective even in dry areas with as low as 40% humidity.

Unlike existing solar-powered water harvesters that involve complex two-stage processes—first absorbing water from the air and then heating the saturated material to extract the water—the new system operates more seamlessly.

Traditional systems require manual switching between stages, adding to their complexity and cost. The new harvester developed at KAUST eliminates this need by passively cycling between water absorption and extraction stages, inspired by natural water transport in plants.

“Our initial inspiration came from observing natural processes: specifically how plants efficiently transport water from their roots to their leaves through specialized structures,” said Kaijie Yang, a post-doctoral fellow at KAUST and the lead on the study, in a statement.

The innovative design features mass transport bridges—vertical microchannels filled with a salt solution. These channels use capillary action to draw up water, which then diffuses back down as the solution becomes concentrated. This continuous cycle optimizes the transport of water and heat, enhancing the system’s efficiency.

“By optimizing the transport of mass and heat within the system, we enhanced its efficiency and effectiveness,” said Tingting Pan, another post-doctoral fellow at KAUST who worked on the project.

Tests showed that each square meter of the system could produce two to three liters of water per day in summer and one to three liters in fall, demonstrating its effectiveness in real-world conditions. The system was successfully operated without maintenance for several weeks and showed potential for use in irrigation, particularly for desert plants and crops like Chinese cabbage.

The researchers selected affordable materials such as water-wicking fabric, a hygroscopic salt, and a plastic-based frame to ensure cost-effectiveness. This approach aims to make the system viable for large-scale deployment in low-income areas, offering a practical and economical solution for off-grid freshwater generation and irrigation.

“The materials we used were a water-wicking fabric, a low-cost hygroscopic salt and a plastic-based frame. We chose the materials for their affordability and availability, so we anticipate the cost is affordable for large-scale application in low-income areas,” said Qiaoqiang Gan, one of the study’s senior authors.