The Swiss Institute for Environmental Science and Technology has developed a method for developing nations to increase their access to clean water. The process is very straight forward, involving only a clear plastic bottle, non-potable water, the sun and the roof of a house or a corrugated piece of metal. The water is kept in ts he suns rays for a time of 6 hours to 2 day depending on the strength of the sun and the UV rays kill pathogenic organisms in the water that cause cholera and diarrhea.
Isn’t it great to see such a straight forward method promoted that can improve the life’s of so many people, especially children, worldwide? And it gives new life to plastic bottles that would be otherwise thrown out.
You can check out the SODIS (solar water disinfection) project here
This picture comes from the SODIS project website