Clear water from a backpack

September 24, 2012

Access to potable water is one of the most fundamental factors in the quality of life of individuals and the development of entire communities. However, water scarcity is still a common problem in many developing countries. The difficulties are particularly acute in rural areas, where people often also have to walk long distances in order to fetch water from a source and carry it back home in heavy water containers. Additionally, this water will often be contaminated by bacteria, viruses and parasites, causing serious health problems for the communities concerned. Pasteurisation of water is a way to solve this problem. However, boiling water to the required temperature often necessitates great consumption of energy – which, again, is often not available.

The Solar Solution Laboratories found a way to  tackle both the problems of transport and pasteurisation. The so-called AquaPak is a portable and cost-effective solution as it consists of low-cost polyethylene with UV inhibitors, a transparent bubble-pack sheeting on one side and a black surface on the other. AquaPak relies only on sunlight and the black side aids in heating the water to a temperature of 67 °C (152 °F). Maintaining this temperature for about 15 minutes reduces the presence of all pathogens by 99.999%.

But how do you know that the required temperature has been reached? Inside the sealable bag, there is a small built-in glass tube indicator filled with coloured wax. This wax melts when the required temperature has been reached. If circumstances are ideal and steady sunlight is available throughout the day, AquaPak is able to produce about 15 l (4 gallons) of safe potable water a day.

Caroline Weimann
Caroline Weimann

Caroline Weimann is member of the “empowering people. Award” team at the Siemens Stiftung (foundation). She studied International Law, Economics and Diplomacy at the School of Oriental and African Studies in London as well as Languages and Literature at the University of Oxford. Before joining the Siemens Stiftung, she worked on health and development issues at the European Commission and at a consultancy firm for non-profit organizations.


Basic Needs & Social Entrepreneurship


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