For many people from urban areas the access to potable water is very low. To combat the water crisis, scientists had to design systems that can help provide clean drinking water from something that is omnipresent. According to the researchers at an average 64% humidity, a cubic meter of air carries about 11.5 milliliters of water. In conclusion if the water is extracted, it cans solve the problems of billions of people living in rural areas.
Reserachers at the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB have found a way of converting air humidity into potable water. “The process we have developed is based exclusively on renewable energy sources such as thermal solar collectors and photovoltaic cells, which makes this method completely energy autonomous. It will therefore function in regions where there is no electrical infrastructure,” says Siegfried Egner, head of department at the IGB.
The principle of the system is as follows: it makes use of hygroscopic brine which absorbs moisture. When this solution is made to run down a tower-shaped unit, it sucks up water from the air, which is then fed into a tank a few meters off the ground in which a vacuum prevails. Energy from solar collectors heats up the solution converting water to vapor, which is then condensed. “The concept is suitable for various sizes of installation. Single-person units and plants supplying water to entire hotels are conceivable,” says Egner.