High-performance atmospheric water harvester (HYVEST)

Ensuring sufficient fresh water for the global population is a key challenge of the 21st century. Sorption-based atmospheric water harvesting (SAWH) using hygroscopic hydrogels offers a promising solution as a regular water source for dry rural regions (1), as an emergency backup (2) and for outdoor activities (3). SAWH involves three steps: capturing humidity with a sorbent, heating it to release water vapor (e.g., via solar energy), and condensing it into potable water. Efficient materials for SAWH need high surface area for humidity capture and good thermal conductivity for vapor release. The HYVEST project addresses this by developing thin, uniform hydrogel coatings on aluminum and carbon foams. Initial dip-coating tests on flat samples were successful. Now, the method will be extended to 3D foams, creating lightweight, efficient composite sorbents, which represent the central innovation of our SAWH device. Thereby, we aim to create an economically competitive water harvester that offers a direct technological response to the global water crisis.