The Science

SolarSack’s purification technology is based on Solar Water Disinfection (SODIS) technology. This 25-year-old process has been endorsed by the World Health Organisation (WHO) as a safe way to purify water.


We value our customers’ trust. Our SolarSack has been rigorously tested by government-approved reference laboratories and certified by global bodies to prove its efficacy.

Research & Development

We are committed to a human-obsessed approach to our product development. We have implemented a rigorous monitoring and evaluation framework throughout our product lifecycle to helps us improve our product and respond to the changing needs of our users

Meet the team behind the SolarSack innovation

Third Party Testing

Independent third-party laboratories have rigorously tested SolarSack’s performance efficacy for the removal of bacteria and virus from water sources and the release of chemicals to the water. The results show:

Microbial reduction after 4 hours of treatment with sun

99.99% bacteria reduction

  • Escherichia coli
  • Total Coliform

99.9% virus reduction MS-2 bacteriophage (surrogate microorganism used by WHO for testing virus performance).

Chemical migration

All materials comply with EU standards and show no harmful levels of chemicals released to the water by SolarSacks, even under worst case conditions.

Local Certifications

SolarSack has achieved certification and authorization by local governments in Uganda, Ghana, Rwanda, Kenya and Nigeria, where the SolarSack’s performance efficacy has been tested by government-approved qualified reference laboratories.

The Scientific Process


The SODIS process removes harmful pathogens by harnessing UV-rays and heat from the sun. UVA forms Reactive Oxygen Species in the water that play a critical role in deactivating the microorganisms. UVB directly damages the organism’s DNA and RNA.


The heat initiates the pasteurisation process alongside the UV-rays to accelerate the disinfection process. This additional stage removes harmful microorganisms.​

Human First Methodology

We are committed to a human-first approach to our product development. Our monitoring and evaluation studies help us optimize our product design. 

The SolarSack’s innovation lies in the specialized plastic foil that increases solar penetration, killing a more comprehensive range of microorganisms at a faster rate.

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Our Lab

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My name is Charlotte Frydenlund Michelsen, and I’m the Senior Science Manager at 4Life Solutions… SaWa by 4Life can produce safe drinking water, showing over a 99.999% reduction of E. coli. Going forward we will be testing with turbidity levels of over 100 NTU

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Project guide