The invention filters out the bacteria, salt and fibres from the clothing, and lets only the water molecules in the form of steam to pass through. The technique is called membrane distillation, and it is commonly applied on space stations to clean astronauts’ urine. Tests showed that the water is cleaner than what comes out of the local tap.
The machine was designed and built by Andreas Hammar for Unicef to promote their campaign on scarcity of drinking water around the world. The device was launched on Monday at the Gothia Cup- the world’s largest international youth football tournament, and since then more than 1,000 people have tested its product.
The creator explains that depending on how sweaty a person is, but a typical amount that can be extracted from one person’s t-shirt is about 10 ml.
Unfortunately, the weather in Stockholm does not do any favors to the inventors, so the demand for sweat turns out to be much greater than the supply. Even installing exercise bikes alongside the machine with volunteers working out continuously does not help.
As Mattias Ronge, chief executive of Stockholm-based advertising agency Deportivo – which organised the stunt pointed out, the machine raises awareness for Unicef, even though it might never be put into mass production.