The Dutch start-up Sponsh, a spin-off company of Eindhoven University of Technology, developed a temperature-sensitive smart textile that absorbs water from the air at night and releases that water by day, inspired by desert animals.

Air contains large quantities of water. Dispersed, the atmosphere contains 12 quadrillion litres of water vapour, almost 10 times the amount of water available in all rivers combined. This water vapour often forms clouds and provides rain. However, in desert areas, few clouds form, yet some plants and animals live in these dry areas.

Sponsh took inspiration from two of these creatures. The Namibian Desert Beetle has hydrophilic (water-attracting) and hydrophobic (water-repellent) areas on its skin to collect water. The webs of desert spiders catch and hold water from the air.

The textile is temperature sensitive. At night, it attracts and absorbs water from the air. In this process, the fibres swell up to four times their size. During the day, the material becomes hydro-phobic, repelling the water if absorbed earlier. The fibres contract and squeeze out the water like a sponge. Extrapolating current lab results, one square metre can produce up to 1.3 litres per day. The material functions completely off-grid and purifies the captures water as well.

The first application is using the material for water producing tree guards. These tree guards not only protect a young tree against sun, wind and animals. They also provide the tree with up to 100 ml of water per day, thus helping the tree to survive the first harsh summers.

Sponsh is still in the development phase. The company plans to prototype the material in real life conditions in 2020 and run the first larger pilots in 2021.

Images: Sponsh