Solvatten is a simple portable device which uses sunlight to purify water for drinking.

Provided the sun is strong enough, it takes two to six hours to produce ten litres of drinking water.

[1] The Solvatten device consists of two hinged parts which can open in the manner of a book, revealing two transparent plastic surfaces.

When the device is placed in the sun, the plastic allows ultra-violet radiation to reach the water, which is also heated by the sunlight.

[2] Use of the device can reduce the use of wood to boil water, thus acting to limit deforestation and carbon dioxide emissions.