In some places, solar is a great green option, but not really a necessity, but in other places, solar power can make a huge difference, and not always just by charging mobile phones and providing clean lighting (which is a huge need in the developing world).
A village resident drinks purified water from the system’s clean water tank.
In some cases, solar energy actually helps to provide another basic necessity, which is clean drinking water, and for the last two years, villagers in the remote Mexican town of La Mancalona, on the Yucatan peninsula, have been getting their potable water from a solar-powered water purification system engineered by researchers at MIT.
La Mancalona, which is home to some 450 villagers, was the recipient of a prototype water station capable of producing 1000 liters per day of clean potable water, thanks in part to the financial support of the W.K. Kellogg Foundation. The system, known as a PVRO, or photovoltaic powered reverse osmosis, unit, was designed and installed by MIT students and research staff, and the village was chosen because it both receives “ample amounts of sunshine” and it lacks a dependable source of clean water.
Because of the PVRO water station, the villagers, who are mostly subsistence farmers and beekeepers, now have reliable and affordable source of drinking water, and the water produced by the station can be sold at a profit by the village, serving two beneficial roles in the community. The water, which is sold for 5 pesos per 20-liter bottle, is 1/10th of the cost of bottled water that comes from a facility about an hour away from the village, and yet it has turned a profit of about 49,000 pesos ($3,600) per year, so it’s a viable business for the community.
The system uses solar panels to charge batteries, which then power the pumps that push both brackish well water and collected rainwater through the filtration membranes, as well as supplying the UV sterilization bulbs with electricity. According to MIT News, some of the residents of the village have been operating and maintaining the PVRO system for almost two years, taking care of filters and batteries and UV bulbs and water testing, and express that it improves their lives. In fact, the positive effects of the water station might also be secondary, as noted in this anecdote from one of the MIT researchers, Huda Elasaad:
“Before, they couldn’t afford clean water, but they could afford soda, which was actually cheaper than bottled water in that village. Now we see a shift: These children are drinking more water and becoming more healthy and hydrated.”
Another side effect of the development of economically feasible solar water stations like this one is that they could also be appropriately developed to fit so many other specific applications, not just for a village or community:
“This technology would enable hotels, schools, hospitals, governments, et cetera, to produce water at a greatly reduced price. The technology MIT has developed is capable of producing economic value in these countries. – Steven Dubowsky, professor emeritus of mechanical engineering at MIT
The team produced a case study of their solar powered water system, which is available at Science Direct, and which found that their data “suggests that PVRO clean water is a viable approach for rural communities.”
Photo: Leah Kelley
