Echoing Green is a non-profit organization that provides support to entrepreneurs with solutions to social issues worldwide. Once an entrepreneur presents their idea, they are granted 90 thousand dollars to start their business. Financial advisers and other professionals support each business as they take off with their innovations. I chose to cover three such innovations and their creators on the blog today because I find non-profits essential to humanity. Sometimes it gets discouraging to think about how much financial support is needed to start a business. With Echoing Green, those issues are taken care of and inventors are allowed to do what they do best. They are free to create.
Black tarp, plywood, plexiglass, tubes, clamps, and a bucket is all you need to make a thermosiphoning Simple Solar Water heater according to Renewable Energy UK at http://www.reuk.co.uk/Simple-Solar-Water-Heating.htm. This set up looks a lot like a maze. Except instead of a little ball, water shoots up through the small space between the plexiglass and the tarp. As it heats up, the water passes over the hot black tarp surface, disinfecting it. It travels upwards (known as thermosiphoning) as the temperature increases which increases the flow and therefore gives pollutants in the water a longer time to decay. The tubes connect the water in the bucket to the “maze” and are clamped in place. This setup is an estimated $30 but can also be made out of recycled parts. Some designs attach the water tank directly to the “maze” without using tubes. Shown below is a Simple Solar Water Heater in Pakistan:
According to the World Health Organization, “Globally, there are nearly 1.7 billion cases of diarrhoeal disease every year”. Diarrhea is the number one cause of malnutrition in children under 5. It kills 760,000 children under five years old each year. Diarrheal illness can be caused by contaminated food or water, or lack of sanitation practices. Children come into contact with feces through many routes, like unwashed hands, open sewage, groundwater, or insects. The major route that SODIS closes off is contamination through water. SODIS stands for solar disinfection, and the type of disinfection referred to here is using Polyethelene Terephthalate bottles and UV radiation to kill off bacteria. PET bottles allow sun rays to reach the water without releasing chemicals from the bottle. Several bottles at a time are filled with contaminated water and placed on roofs or tables. After six hours water is safe to drink. My only concerns are the cost (it appears as though the people who use SODIS were given a donation of PET bottles) and the quantity of clean water that is typically produced with this method. Nevertheless, this is a simple solution that can be easily implemented.
Here is more information: SODIS document.
The image of the SODIS bottle has changed a lot since 1991. Here is a more modern website: Solar Bottle.