Go Green to Go Clean? Making Use of Solar Energy and Throwaway Water Bottles to Save Lives

The following doesn’t have much to do with our usual energy discussions, but the information was fascinating to me so I thought I’d share it. If this is news to you, I’ll bet you’ll never look at a plastic water bottle the same way again.
 
Everyday over 4500 children die of dehydration due to diarrhea caused by infectious organisms. When a small child, particularly a baby, gets infected by cholera or some other virulent organism that damages intestinal linings, the end can come quickly, often within a day. If proper medical help is available intravenous injections of fluids can save their lives. But in less developed nations that intervention is often not available in time. Even if clean water is available, it’s often not possible to get enough fluids, by mouth, into the bloodstream in time to save the life.
 
The key is prevention.
 
But anyone who has traveled to developing countries knows how difficult it can be to avoid water-borne infection, even in the cities, much less in the rural communities. And boy, does the Mauldin family know that from personal experience.
 
Our daughter Kris, and one of our sons, Daniel, took a trip to South America to celebrate graduating high school and college. They both came down with cholera while staying at a village on the Amazon. They survived to finally make it home, thank God, but they were very ill.
 
I didn’t escape either. While on a work related trip to India I was infected with shigella, and two other organisms. On my return to the US I spent a week in the hospital while doctors rehydrated me and tried different antibiotics. I was weak for months.
 
The best solution is to prevent disease by having non-infected drinking water available. Yes, of course, water can be boiled and cooled or chemically treated. But making those methods consistent practices among long established native cultures seems impossible.
 
But, the ubiquitous water bottle, possibly because of its association with style, fitness and urban sophistication, has gone where chlorine tablets never could.
 
In the 1980s some Lebanese scientists found that the UVA spectrum in direct sunlight can kill organisms – viruses, bacteria and parasites – in water and make it safe to drink.
 
There wasn’t much follow-up to this research until, in the 1990s the water research institute Eawag, the Swiss Federal Institute of Aquatic Sciences and Technology developed a clever way of easily applying this research to save millions of lives. The method is called SODIS, the Swiss acronym for safe water disinfection and it’s very simple: Take an ordinary plastic water bottle (made of PET or polyethylene terephthalate, which is the usual material), tear off the label, fill it with water from almost any source – puddle, drain pipe, creek – as long as it’s not too muddy or murky. Cap the bottle and lay it on a piece of somewhat shiny metal (corrugated roofs do nicely) and leave it in the sun for six hours.
 
That’s it – easy. The water is safe to drink say the experts.
 
Want proof? It’s difficult to get some communities to use the disinfected water exclusively, but even so the results have been dramatic. In Kenya, during a cholera outbreak, children under the age of 6 in the SODIS protected villages had about 90% less cases. A recent article in National Geographic quoted a school official in Tanzania as stating that prior to the school using SODIS, absenteeism due to diarrhea resulted in only 10 to 15 percent of the students passing the national sixth-grade exams. Now 90 – 95 percent of the children pass.
 
So the next time we go camping I might just pack some aluminum foil in case something happens and we need to refill our water supplies from a mountain stream. We always carry filled water bottles so we always have empties in the trunk of the car.
 
As I said, I’ll never look at an empty plastic water bottle in the same way.

About the Author

Editor:

Paul Mauldin

Paul earned his B.S. and an M.S. in electrical engineering from the University of California-Berkeley and is a registered professional engineer. He has worked in the energy industry for more than 25 years, developing and implementing advanced energy technologies. As research director for Pacific Gas and Electric Co. he pioneered methodologies used in the design, maintenance and control of energy delivery systems. As a consultant he has provided guidance to utilities and the vendor community, nationally and internationally.