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Experimental Solar Powered Water Heaters

Last week I talked about my experience designing and implementing "eco-latrines" in Cotani, Bolivia. As a member of the Oklahoma East chapter (OK East) of Engineers Without Borders-USA, our new project involves implementing experimental solar powered water heaters in the community to improve the bathing experience.

The Idea for Solar Powered Showers

Because of cold temperatures in the mountains of Cotani, and lack of hot water, most citizens don't shower or wash their hands. Who can blame them—cold showers aren't a pleasant experience! Additionally, the people of Cotani believe that washing in the cold water brings sickness.

Our professional chapter has been helping the University of Tulsa (TU) student chapter to implement their design of experimental solar powered water heaters, providing the community with warm water for showers and sinks.

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Design of the Solar Powered Water Heaters

The students' design uses two-liter bottles found along the side of the road (trash is either thrown out or burned in rural parts of Bolivia), and PVC pipe that has been painted black.

The ends of the bottles are cut and slid over the PVC pipes which are then placed on the roof of the building in a winding manner to increase surface area and collect more heat (acting like a green house). The PVC pipe is connected to existing plumbing so when showers or sinks are turned on, the warm water is supplied.

Coming straight out of the pipes, the water is only about 40 degrees Fahrenheit. But after implementing the solar heaters, I believe we got the temperature up to around 80 degrees.

Implementing the Heaters

In May, I traveled with the students to teach the citizens of Cotani how to implement their own heaters, as well as taught the science behind heat transfer and the importance of proper hygiene. The citizens were very receptive and really liked the idea of having warm water.

Instructions and materials were left for the community members to help teach the community about how the heat exchanger works and importance of hygiene. The TU students went back on a second trip to give additional instruction to the community leaders about how to construct the heat exchangers, so they could be more self-dependent and not rely on us to build them.

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After being a member with the OK East chapter for about two years, as well as being involved as a student at OSU-Stillwater, I'm consistently amazed at how much we're able to impact people's lives in developing countries. Seeing how happy the community is and seeing smiles on the children's faces drives me to be even more involved.