'Solarsack' cleans water with heat from sunlight, cheaply and effectively

Anders Løcke and Louise Ullmann, who study Architecture and Design at Aalborg University (AAU), have designed a better and cheaper system for purifying drinking water in developing countries.

The product, known as SolarSack, is a special bag that is filled with four liters of water and placed in the sun for four hours. Using UVA and UVB rays, as well as heat from the sun, the water is cleaned of pathogenic bacteria. The user can then drink the water and reuse the bag for water purification.

The method was approved by the World Health Organization which estimates that between 99.9 and 99.999 percent of the pathogenic bacteria in the water die. The students tested SolarSack in Kenya and Uganda with local users and organizations, and adapted it to their needs. And it's cheap.

"We estimate that a SolarSack can be produced for less than one and a half Danish kroner, 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, says" Louise Ullmann, AAU.

Developed in East Africa

With a price of about a dollar apiece including distribution, the SolarSack will cost about the same amount as a bucket of coal. But where a SolarSack supplies at least 500 liters of clean drinking water for a dollar, a bucket of coal provides less than 100 liters of water.

More than 47 million people in East Africa do not have access to clean drinking water, and 80 percent of all diseases in the region are due to poor water and sanitation conditions. The most widespread method of purifying water in the region is boiling, but this requires coal or wood, both of which are expensive and harmful to health and the natural environment.

As part of their studies in Architecture and Design at Aalborg University, Anders Løcke and Louise Ullmann went to East Africa to investigate the problem. The goal was to design a better solution.

"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," says Anders Løcke, AAU.

On the way to mass production

On June 21, SolarSack won the Danish edition of the ClimateLaunchpad competition for green startups. They now go on to the international final on Cyprus in October where they can win funding and assistance to further develop the project.

The two students behind the project just graduated from their program at AAU, and Anders Løcke will now work full time as CEO of SolarSack. He was offered a partnership with Access2innovation in Aalborg which specializes in sustainable solutions and business development in Africa. The Red Cross is also interested in the project.

"Red Cross Kenya is valuable as both a sparring partner now and later as a customer, so we're really pleased that they're interested in collaboration. As an established NGO, they have the ability to get SolarSack out to all corners of the country that need water purification," says Anders Løcke, AAU and SolarSack.

Anders Løcke will now speak with several organizations that work with the development and sale of products for relief. The plan is to get SolarSack into production and distribute the product to NGOs and the private sector in East Africa.