SolarSack water purifier taps sun to bring clean H20 to developing regions

A team of Danish students have developed what they’re calling an affordable and sustainable solution for purifying water in developing regions. The system, dubbed “SolarSack,” includes a 4-liter pouch that purifies water when placed in direct sunlight for four hours.

SolarSack works by harnessing heat from the sun, as well UVA and UVB rays. These elements combined eliminate more than 99.9 percent of the pathogenic bacteria in the water, a figure the team says was affirmed by the World Health Organization, which has approved the method. The system has so far been tested in villages, refugee camps, and slums in Kenya and Uganda.

“After the first study in Uganda, it became clear that the use of coal and wood constitutes a major threat to the natural environment, and the price of fuel increases as forests are cleared. So we decided to use sunlight as a resource for water purification. There is plenty of sunlight in Africa, and it’s free,” designer Anders Løcke said in a statement.

As a result, SolarSack’s creators have managed to keep its price down to just about $1, with most of the costs coming from distribution. That puts its price on par with a bucket of coal, although SolarSack may provide five times more clean drinking water.

“We estimate that a SolarSack can be produced for less than one-and-a-half Danish kroner (about 25 cents), transported, and end up in the hands of the user for less than a dollar. The bag can be reused 150 times, making it significantly cheaper than the alternatives,” said Louise Ullmann who led the project with Løcke.

Accessing potable water is a struggle for many people living in East Africa, where more than 47 million people are without it and where around 80 percent of diseases are a result of poor sanitation. With SolarSack, Løcke and Ullman hope to provide an alternative to boiling water over a wood or coal fire, which is currently the most common method for purifying water, but has negative consequences on the health of people and the environment.

Løcke and Ullman recently won a green startup competition in Denmark. They are now competing internationally for funding and help in developing SolarSack further at the ClimateLaunchpad in Cyprus.