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

• Published in: Nature communications 2024-07, Vol.15 (1), p.6260-9, Article 6260
• Main Authors: Yang, Kaijie, Pan, Tingting, Ferhat, Nadia, Felix, Alejandra Ibarra, Waller, Rebekah E., Hong, Pei-Ying, Vrouwenvelder, Johannes S., Gan, Qiaoqiang, Han, Yu
• Format: Article
• Language: English
• Subjects: 147/135; 639/4077/909/4101/4103; 639/638/169; Alternative energy sources; Arid environments; Atmospheric water; Clean technology; Climate change; Design optimization; Drinking water; Energy utilization; Engineering; Food supply; Fresh water; Heat treating; Humanities and Social Sciences; Humidity; Irrigation; Irrigation systems; Irrigation water; Mass transport; multidisciplinary; Porous materials; Relative humidity; Science; Science (multidisciplinary); Solar energy; Sorbents; Sun; Sunlight; Systems design; Water; Water scarcity
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-50715-0

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 −2 h −1 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 −2 per day of freshwater during the summer and 1.0–2.8 L m −2 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. Solar-driven atmospheric water extraction (SAWE) systems have the potential to address the ongoing freshwater scarcity, but they can only produce water intermittently. Here the authors developed a SAWE system with optimised architecture to achieve continuous freshwater production under sunlight.