A solar-driven atmospheric water extractor for off-grid freshwater generation and irrigation.

Yang, Kaijie; Pan, Tingting; Farhat, Nadia; Felix, Alejandra Ibarra; Waller, Rebekah E; Hong, Pei-Ying; Vrouwenvelder, Johannes S; Gan, Qiaoqiang et al. · Nat Commun · 2024

Where this comes from

Abstract

Solar-driven atmospheric water extraction (SAWE) is a sustainable technology for decentralized freshwater supply. However, most SAWE systems produce water intermittently due to the cyclic nature, with adoption hindered by complex design requirements or periodic manual operations. Herein, a fully passive SAWE system that can continuously produce freshwater under sunlight is presented. By optimizing the three-dimensional architecture to facilitate spontaneous mass transport and efficient energy utilization, this system can consistently produce 0.65 L m<sup>-2</sup> h<sup>-1</sup> of freshwater under 1-sun illumination at 90% relative humidity (RH) and functions in arid environments with an RH as low as 40%. We test the practical performance of a scaled-up system in Thuwal, Saudi Arabia over 35 days across two seasons. The system produces 2.0-3.0 L m<sup>-2</sup> per day of freshwater during the summer and 1.0-2.8 L m<sup>-2</sup> per day of freshwater during the fall, without requiring additional maintenance. Intriguingly, we demonstrate the system's potential for off-grid irrigation by successfully growing cabbage plants using atmospheric water. This passive SAWE system, harnessing solar energy to continuously extract moisture from air for drinking and irrigation, offers a promising solution to address the intertwined challenges of energy, water, and food supply, particularly for remote and water-scarce regions.