Editor's Note: Students from Dartmouth's Thayer School of Engineering are working in Tanzania to help improve sanitation and energy technologies in local villages. This series chronicles work being done by the student-led group, known as  Dartmouth Humanitarian Engineering (DHE) [formerly known as Humanitarian Engineering Leadership Projects (HELP)], to design "rocket stoves" in the village of Mwamgongo and top-light updraft design (TLUD) gasification stoves in the village of Kalinzi. The goal is to create a healthier, more energy-efficient cooking apparatus that these villagers will accept and use. DHE students are filing these dispatches from the field during their trip. This is their 21st blog and final post for Scientific American.

Dartmouth Humanitarian Engineering (DHE) has spent a few years working in Tanzania, but only recently have we stared to see our version of a rocket stove spread rapidly across the region. While numerous people have all been a part of this accomplishment, a few individuals in each of these small villages in Tanzania created a tipping point for the local distribution of the technology. All we did was find them.

When Zach Losordo started working on creating a new rocket stove design this summer in the village of Mwamgongo, he met with a group of interested individuals, showed them his idea for a new rocket stove and invited them to come back the next day to learn the construction methods. That evening, a man by the nickname of Kambe Yote came to Zach's field station, measured the stove and made it correctly in his own home without any instructions. He went on to lead Mwamgongo's stove distribution program, which has already resulted in over 150 stoves being built.

When I arrived in Mwamgongo, I met with the village stove builders and Kambe Yote. I told them that I would teach them how to build the haybox, and I explained the concept and design. The next morning we met with everyone and Kambe Yote informed us that he had once again already built the technology on his own. He invited us to his home and sure enough, he had built a haybox perfectly attached to a new rocket stove with two combustion chambers—his own design. Kambe Yote is a maven whose knowledge of carpentry and respect in the village launched our first stove program, and I felt fortunate to meet him.

When working in Sunuka, our meetings often started an hour or two after the proposed meeting time. However, two gentlemen by the names of Prosper and Alex always arrived around 10 minutes early, and they often stayed even after the rocket stove seminars were over to learn more. Prosper and Alex are social connectors. Alex has built hundreds of stoves so far after traveling to the nearby villages where his family and friends live. On another hand, Prosper conquered Sunuka and other nearby areas. Propser seemed to be well liked, as he kept the group laughing throughout the seminar. He also tried talking to me for hours one night when my translator was gone even though my Swahili was caveman speech at best. I am confident that Alex and Prosper (who ironically didn't know the meaning of his name until I told him) will thrive in the future with their new marketable stove skills.

But, it was in my last week working for DHE in the village of Kalinzi that I met someone whose ardor for change revived my spirit, which had suffered many doubts after working on an aid project that challenged traditional cooking for several months. His name was Pascal Samuel, and he was 18 years old. He was a passionate salesman that immediately understood how important preventing complete deforestation would be for his generation. This young boy heard us when we were talking at the secondary schools, and he consequently came to our home that afternoon in hopes of learning more about the rocket stove. Excited by his enthusiasm, we started to build a rocket stove with Pascal, and halfway through, he took over. For the next three days, Pascal came to our home after school. We taught others how to build the stove, but Pascal did most of the talking and the building.

One day, the rain kept us all inside, and Chris and I proposed the idea of writing a song about the stove. Pascal became very excited. The next day Pascal came with several verses of lyrics about saving the community from deforestation with a new innovative stove. Chris and I took turns on the guitar while Pascal belted notes from his soul.

During our last day in the village, we built a stove in the market and many villagers gathered around. When we had everyone's attention, Chris and I sat down, and Pascal stood up. He stood in front of both the rocket stove and the traditional three-stone stove, and he lectured with fervor to members of his community. He told them it was time to stop using a stove that caused damage to their environment and lungs. Soon, everyone was asking how they could have a stove built in their own home.

The incredible thing about all the individuals I have mentioned is that they live at the bottom of the economic pyramid. They all live on less than about two dollars (U.S.) a day. But when given a little education and an opportunity to help their community, they made the rocket stove flourish in the Kigoma district. After only a few months of working with these incredible individuals—and Jane Goodall Insitute—thousands of stoves have been built. I believe we have finally passed the tipping point.

Image of Prosper courtesy of Tim Bolger

Image of Pascal courtesy of Chris White