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"What did I get myself into?"

The thought tugged at the corners of Ben Adams's mind as he took in the vastness of the surrounding African landscape. A senior majoring in mechanical engineering at Iowa State University, Adams jostled against six companions in a cramped SUV that had been traveling the deeply rutted, nearly non-existent road for hours under a merciless sun, their progress punctuated by a broken strut and a flat tire.

The end of their journey was Nana Kenieba (Figure 1), a village of about 800 souls situated in southern Mali, one of the ten poorest nations on Earth. For these people, something as basic as drawing a drink of water or cooking a meal can be an arduous, even perilous, process. As part of a collaborative effort of Engineers Without Borders- USA (EWB-USA), the TMS Foundation, and the Iowa State University Material Advantage chapter, Adams and his fellow Iowa State students (Figure 2) were hopeful they could make a positive difference at Nana Kenieba by developing sustainable approaches to securing a clean water supply, safe, efficient energy, and more durable housing. What some of them weren't prepared for was how much they would receive in return over their 14-day stay in May 2010. Said Adams, "I expected the villagers to be completely different, but they are actually a lot like us, and we are a lot like them. They are concerned about their families, how they can provide for them, and how they can make a better life for their children."

"They have so little and struggle to make a living, but they enjoy life the same amount that we do—even more," echoed Bill Hall, another senior Iowa State mechanical engineering student. "While we were there, they had parties, music, and several wedding celebrations. They are a very community-driven people with huge families who work well together. They value things that I think we don't value enough."

"I was sad to leave," said Adams.

While Iowa State has maintained a relationship with Nana Kenieba for several years, the focus of this trip was to lay the groundwork for devising a ceramics production process for stove bricks, water fi lters, and building materials using local supplies and expertise. Funded in part by the TMS Foundation, the project marked the first time that EWB-USA had ever teamed up with Material Advantage to apply materials science and engineering principles to sustainable development.

"We selected this set of projects because they form an integrated approach to poverty alleviation," said Nathan Johnson, Iowa State graduate mechanical engineering student and program manager for this particular effort in Mali. "The projects are mutually supportive and meet needs that are more than the sum of their parts."

A challenge in implementing any aspect of the project was ensuring that its promises of improvement did not yield unintended consequences that would have made it difficult to incorporate and sustain within the village's fabric of life. Johnson and Hall experienced this first-hand in trying to developing a safer, more fuel-efficient method of cooking than the open "three stone fire" used by most families in Nana Kenieba (Figure 3). Their approach entailed design of a cooking stove with a ceramic combustion chamber, built from fire bricks of clay and biomass.

Part of Hall's work in Mali encompassed designing and testing a brick press (Figure 4) to ensure uniformity of the bricks, while also facilitating production. As part of the engineering assessment process, he also investigated methods readily available in the village that could potentially be used to fire the bricks. Although the Iowa State team anticipated that a community kiln, managed as a local business, might be necessary to properly sinter the bricks, Hall pointed out, "A kiln is a pretty substantial structure. We needed to make sure it was the most feasible option."

"We worked with local potters this trip to get a better understanding of their firing methods, technologies, materials, and skill set," he continued. "This helped us narrow in on a firing strategy so that the approach we ultimately take is one the villagers can accept and sustain."

The search for a sustainable stove brick also involved experimentation with different material combinations to help achieve the desired strength and insulating properties. "Clay is everywhere, but there is quite a bit of variability in the quality of clay," Hall said. "We also tried different ratios of clay to biomass to define a combination that held together well and was easy to press. In addition to straw, we tried peanut shells, since peanuts are a main crop there. But, it takes quite a lot of peanut shells to make one brick. And, it also takes a lot work to get the clay suitable for making bricks—it has to be mined and then the hard chunks need to be crushed into powder (Figure 5) and mixed with the biomass and water. Whatever solution we come to, we need to make this an easier process."

Hall said the local potters were very interested in his stove design, but incredulous about his methods. "As part of our assessment, we were using an open pit fire (Figure 6) to fire the bricks. While we were laying sticks in the pit, the potters told us we were making 'really bad bricks,'" said Hall. Part of their reaction, he explained, was based on the appearance of the bricks before firing—rough and lightweight from the biomass, rather than smooth, dense, and artistic like the cooking pots that they made. However, at the end of the firing process, the potters' predictions proved accurate. "They were right. They were bad bricks," Hall said. "As we suspected, the fire didn't get hot enough to burn away the biomass or vitrify the clay, so we ended up with crumbly bricks."

While Hall's experimentation with brick production methods points to the kiln as the best possible solution, Johnson noted that a number of variables must be considered and tested before committing to that path. "We have to factor in what it takes to make a brick, the cost of the brick, and then ask ourselves, 'Is this going to save that much over the life of the stove? Will this design really use less wood than a three stone fire or reduce indoor air pollution? How will this approach affect the users and the environment?' None of these have easy answers."

To gain needed insight into the potential impact of the new stove design, Johnson conducted a series of stove emissions and efficiency tests while in Mali. "Our goal was to start getting a picture of what the needs are, which is vital to taking any next steps," said Johnson. He noted that like the brick production, defining the optimal stove design is proving a complex process. "You have to gain a lot of understanding into how people use a stove," he said. "Different wood, a different type of meal, family size, and duration of cooking can all have an affect on the emissions. It will take a couple of trips to fully evaluate that."

Johnson conducted many of his stove tests in a kitchen that the students had built during their stay for the village midwife (Figure 7). "We really had no input into the building of the kitchen," said Hall. "We wanted it to go somewhere where it would be used, so we let the midwife make all the decisions as far as placement in her yard, location of the door, and the size of the windows. We wanted it to be as organic as possible in order to better understand the current abilities and technology in the village."

Built with mud bricks cured in the sun for several days, the kitchen was not only intended to provide a testing environment for stove emissions, but also offered the students valuable insights into the local building materials and construction processes. Most homes in Nana Kenieba are wooden lattice structures reinforced with dried mud, or daub, and degrade significantly during the rainy season (Figure 8). Johnson said that subsequent visits will explore potential modifi cations to construction methods and materials to improve the durability of village dwellings.

While one student team worked on stoves, and another evaluated construction methods, a third focused efforts on improving quality and accessibility of water. One aspect of this particular project was performing water quality testing using a filter developed by Potters for Peace in 1999 when Hurricane Mitch devastated Nicaragua. Comprised of a clay and biomass combination that creates pores to filter particulates when fi red, the device is coated with colloidal silver to kill E. coli contamination. The Iowa State students had modified the design to increase filter life by incorporating a rounded bottom to remove stress concentrations. However, the primary concern at this phase of the project was "to get an idea of what was going on with the water in the village," said Adams. "We needed to determine the type of water that they have, including pH levels, total dissolved solids, and bacteria."

Concurrent with the water testing was the introduction of a simple pump to assist local farmers with watering their crops. "Many of them spend half a day gathering water," said Adams. "If they could cut that labor back, they would have more time to actually farm and make a little more money."

The students constructed the pump in the community garden (Figure 9), at the request of the village water council, so that as many people as possible would have a chance to test it. The hardest part of the process, said Adams, was developing a supply chain. With the help of the driver who managed the "chicken bus,"—the truck that occasionally delivered supplies to the village from Mali's capital city of Bamako— the team was eventually able to secure all the necessary materials locally for building the device. Using an old bicycle wheel in part of the construction further enhanced its affordability.

"There is nothing remotely close to a Lowes or Home Depot there," said Ben Halls, an Iowa State graduate student who worked on the water team. "You always need to find a compromise between the best possible design and what resources are actually available."

Defining those compromises is the next challenge ahead for the students as they sift through the data they gathered in May to develop more effective designs and strategies for the next visit. "They discovered that several of their assumptions were not correct, which is normal," said Mark Bryden, faculty advisor and chief engineer for the trip. "But now they have the necessary information to begin a detailed program focused on finding an approach to manufacturing high-quality stove bricks in a remote sub-Saharan village. It is an important step to finding a sustainable, local, and culturally viable solution."

Bryden first began working with Nana Kenieba in 2006 and helped establish a solar powered lighting system that had a "surprising" economic impact. "Because lighting extends the day, the subsistence farmers are able to work in the evening making baskets and other items for sale in the markets in larger cities and towns, so we have seen an increase in income that we hadn't anticipated," said Bryden.

The lessons learned from developing and implementing the lighting system, Bryden continued, have informed all other efforts undertaken since with Nana Kenieba. "In addition to the normal metrics of sustainability, we really needed to think of the problem of sustainability in terms of developing a small, vibrant village business that helps ensure that the systems we set in place continue to be viable," said Bryden. "This insight is changing how we approach all of our projects."

The May 2010 EWB-USA/Material Advantage trip marked the tenth time that Bryden had journeyed to Mali on behalf of Iowa State. Along with Richard LeSar, Iowa State's chair of Materials Science and Engineering who also serves as faculty advisor for these projects, Bryden works tirelessly to organize the trip logistics, secure funding, build working relationships with the village's leaders, and mentor the students as they put their skills to the test trying to address seemingly insurmountable social issues.

"Taking a project out in the field, unwrapping it, and making it work is much harder than students imagine and is a critical skill that can't be taught in the classroom," Bryden said. "But even more importantly, our students learn that engineering can change the world and their actions as engineers have consequences (Figure10). Some of our students go on to work in nonprofi ts focused on the poor or join the Peace Corps. But, most go to work in corporations where they can continue to have an impact. Realizing that engineers have a personal and corporate responsibility to make a difference for those who cannot afford their skills is an important step forward in addressing poverty, sustainability, and health worldwide. And, these students are prepared to meet this challenge."

Lynne Robinson is a news and feature writer for TMS.