Chile’s Atacama desert is famously dry, with virtually no measurable rainfall. It is coastal though, with a sea breeze blowing inland. New technology could help draw precious water from the sea air.
Fog traps are mesh screens that capture droplets of fog; when enough water accumulates it runs down into a collector. Fog traps have been used on a small scale since the 1960s, with a square metre of mesh collecting enough drinking water for one person.
Dr Urszula Stachewicz and her team at AGH University of Science and Technology in Kraków have developed a fine electrospun fibre, drawn with electric force rather than being spun mechanically, which could catch fog better. Stachewicz says the material is inspired by spider webs that combine hydrophobic and hydrophilic properties, so droplets initially stick to the fibres and then run off.
Adding a nanofiber mesh makes a fog trap more efficient at catching the tiny droplets that could otherwise pass through wide gaps between fibres. Electrospun fibres are already used in air filters and dust-cleaning cloths and can be mass-produced at low cost.
This simple technology could help provide clean drinking water in many parts of the world that lack infrastructure and which increasingly suffer water stress, even ones as dry as the Atacama.
