Solar-powered gel pulls drinking water from the air

Access to clean drinking water remains one of the world's biggest challenges, with roughly one in four people still lacking a reliable source of safe water. At the same time, growing industries such as semiconductor manufacturing and data centers continue to increase demand on already stressed water supplies. Researchers at Stanford University believe they may have found a promising solution by improving a technology that pulls water directly from the air.

The team developed a solar-powered hydrogel system capable of absorbing moisture from the atmosphere and converting it into potable drinking water—even in extremely dry environments. While similar hydrogel technologies have existed for years, their biggest limitation has been durability. Earlier versions typically began breaking down after only about 30 collection cycles, making them too expensive and unreliable for long-term use.

After several years of research, the scientists identified the primary cause of that degradation and developed a simple solution. By applying an anti-corrosion coating to the metal components surrounding the hydrogel, they were able to dramatically extend the material's lifespan. The improved hydrogel remained stable for more than eight months of testing and successfully completed over 190 water-harvesting cycles without significant deterioration.

The system operates entirely on solar energy. Overnight, the hydrogel absorbs water vapor from the surrounding air. During the day, sunlight heats the material, causing it to release the collected moisture as vapor, which is then condensed into clean drinking water. The current prototype can produce approximately two liters of water per day from a panel about the size of a bath towel, and researchers are working to increase that output even further.

Beyond providing drinking water for remote and water-scarce communities, the technology could also help reduce pressure on municipal water systems by supplying alternative water sources for industries with high water demands. Researchers estimate that, if the technology continues to improve and scales successfully, it could eventually produce water for as little as one cent per liter, making it competitive with traditional water supplies while requiring no electrical grid connection and maintaining a relatively small environmental footprint.