Imagine a toilet that uses concentrated sunlight to heat up human waste to temperatures upwards of 300°C and turn it into sterilized charcoal. As unconventional as it might sound, this “Sol-Char Toilet” was the basis of a Bill & Melinda Gates Foundation-funded project on which BJ Ward ‘09 spent most of her first year as a professional research associate with the University of Colorado (CU-Boulder).
Ward, who earned a master’s degree in environmental engineering with a focus on engineering for developing communities from CU-Boulder in 2013, is fascinated by the intersection of innovative technologies and basic problems like sanitation and energy.
“One of the major barriers to acceptance of these new technologies in developing communities is that there isn’t enough communication between the agencies developing the products and the people who would be using them,” Ward said. “I think as people start to take a more market-based approach, treating people in developing communities as consumers and working intimately with them to develop products that they would be willing to invest in, there will be more and more success for sanitation innovations.”
Ward’s work has taken her all over the world to understand the potential consumers of products that seek to address energy poverty. She got her start not with toilets, but with cookstoves.
Deforestation is a significant problem in many countries, resulting in cooking fuel shortages among rural populations that cook on wood fires. As a graduate student, Ward spent three months in Rwanda as part of Engineers Without Borders. In the western city of Kibuye, she led women’s workshops on how to operate high-efficiency cookstoves that use about half as much wood as open fires. Later, she interned for a month with a NGO in Léogâne, Haiti – the epicenter of the 2010 earthquake – and conducted an assessment of their available renewable energy resources. She taught residents of nearby tent camps to make fuel briquettes from materials such as sawdust, waste paper, and dried agricultural waste. She also took advantage of her immersion in Haitian culture.
“I learned a lot of Haitian Creole, hung out with a Vodou high priest, and rode a motorcycle with three other people on it,” Ward said.
After finishing her graduate program, Ward accepted a position as a research scientist with Waste Enterprisers (now Pivot) and promptly boarded a plane to Ghana. For five months she investigated the feasibility of generating economically viable biodiesel product from fecal sludge. This project, also sponsored by the Gates Foundation, was based in Kumasi, a city of more than two million people with essentially no sewer infrastructure.
“I got to work with some really excellent Ghanaian researchers, and experienced some of the fascinating nuances of actually living daily life in a developing country,” said Ward, whose experiences in Kumasi included commuting to work in a tro-tro – a cramped 14-person minibus which charged a 15-cent fare each way.
Upon her return to the U.S., Ward landed her current job at CU-Boulder and began work on the aforementioned Sol-Char Toilet project. The goal was to build a prototype off-grid system to turn human waste into usable charcoal.
“The results of our studies have been really interesting,” said Ward. “We found that some of the charcoal we were producing from poop had about the same energy as commercial Kingsford charcoal briquettes – which makes them ideal for use in blacksmith’s kilns or cement factories. Also, somewhat surprisingly, the poop-char briquettes don’t smell bad when you burn them.”
Ward traveled to India for a month to showcase her team’s prototype design at the Gates Foundation’s second Reinvent the Toilet Fair.
“There were groups using electrolytic processes to retrieve clean water from urine, there were teams developing products specifically to navigate the difficulties of urban slum sanitation, and Sesame Street was even there with their new Muppet, Raya, who promotes good hygiene and handwashing!” said Ward. “It was the best conference I have ever been to.”
Ward’s interest in recovering energy as a resource from waste stems from research she conducted as an undergraduate with the N.C. Solar Center (now the N.C. Clean Energy Center). For their engineering senior design project, she and fellow Park Scholar Bill Knight ‘09 made a small scale biodiesel reactor that would convert fast food restaurants’ waste trap grease into clean biodiesel. This experience helped Ward understand how developing communities – with a great deal of untreated waste and trash, and little civil infrastructure or government oversight – have the most to gain from incentivizing treatment of waste by giving it commercial value as an energy source.
While the Sol-Char Toilet project concluded in late 2014, Ward is now working with the same concentrated solar energy technology to split water as a source of renewable hydrogen for fuel cells. While she acknowledges that her chosen path is not as lucrative as traditional engineering jobs, Ward finds her current role as a researcher to be deeply interesting and dynamic.
“The opportunities I had access to as a Park Scholar are the reason that I have been able to pursue this professional direction,” said Ward. “When I was a sophomore at NC State, I received a Park travel grant to go to Ecuador with my environmental sustainability class. This trip sparked my interest in travel and gave me the courage to feel comfortable traveling in places where I didn’t know the language or the culture. The leadership and professional training that we received as Park Scholars also helped me tremendously when applying for all of these opportunities – I felt confident presenting myself in interviews because I had so much practice. And finally, I would absolutely never have been able to pursue this line of work with the stress of college loan debt. It’s been wonderful to have the freedom to do the work I love.”