Increasing cooking efficiency for Darfur refugees saves lives
There’s a certain aura of mystery surrounding the birth of an idea, but rarely is the question asked: What’s next? Ashok Gadgil, Ph.D. ’80, knows that the “eureka!” moment is just the beginning; developing and implementing an idea is the hardest part.
The senior staff scientist at Lawrence Berkeley National Laboratory and adjunct professor in Berkeley’s Energy and Resources Group made headlines nationwide last year in Newsweek, O magazine, and other media because he discovered a practical way to help the 2.2 million Sudanese refugees in Darfur. Their tragedy is sadly familiar. Janjaweed militias kill Sudanese men and rape or mutilate women who venture outside the arid refugee camps in search of firewood. By 2005, women were making seven-hour treks for fuel, a necessity that made them susceptible to marauders.
The U.S. Agency for International Development’s Office of Foreign Disaster Assistance was familiar with Gadgil’s creation of an inexpensive water-disinfection system for developing countries. They called him for help in 2004. “Ashok, do you think you can design a conical screw compressor [that creates] a screw-dried, pelletized fuel?” Gadgil recalls the officer asking. He now laughs about the initial request, knowing it is impossible because the refugees simply don’t generate enough kitchen waste to create such fuel. But USAID’s appeal preoccupied him.
“That kept on bugging me that there was no solution. So I kept on digging deeper to find what do they cook; what’s their food like; what are their stoves like?” He realized that current efforts either focused on ending the violence against women or giving food to refugees. Nobody had made the connection that “the [refugees] don’t need fuel, they need cooked food!” Gadgil says, “If I can change the efficiency of this transformer so that I can use a lot less fuel, then I accomplish the same purpose as providing supplemental fuel pellets.”
With this reasoning, Gadgil had a breakthrough. In early 2005, he learned that refugees use three-stone fires in their camps. Gadgil calls this cooking method, which uses three large stones to support the pot, “the most primitive way to cook.” A mere 5 percent of wood’s chemical energy ends up as heat in the pot. Gadgil knew he could design a better stove. “It should be easy, I thought, to figure out how to build a stove that is 20 percent efficient at least, or maybe even 30 percent,” he says.
With funding from USAID and Cooperative Housing Foundation International, an American nonprofit working in Darfur, Gadgil was able to travel to Darfur. He and a team of researchers brought three types of trial stoves with them. In a large public gathering, Gadgil divided the refugees into groups so that they could test the stoves. “We used their parts; we used their cooks; we used their fuel; we used their food and their style of cooking. The only thing we changed was the stove.” Gadgil’s team weighed the ingredients—water, onions, flour, and oil—and tied wood fuel into bundles of 250 grams. “It was a very transparent, easy-to-follow demonstration.”
The winner was the cylindrical, metal Tara stove, originally designed for low-income peasants in India. It looks like a nine-inch-tall tin can and has openings for fuel and air. The cooking pot rests on brackets just beneath the top rim of the stove. It is “multipot,” meaning it functions with pots of different sizes, without a significant loss of efficiency.
The Tara stove doubled the efficiency of the three-stone fires, but Gadgil knew he could do better. In the spring of 2006, he taught a class called Technologies for Sustainable Communities, in which he directed a team in improving Tara stove performance. The team focused on the stove’s two major shortcomings: lack of stability and poor wind resistance. “We modified a number of diameters. Each test would take forever because we had to do everything with wind, without wind, with a small pot, with a large pot, and then we had to test everything three times.” Gadgil and his students added an upper collar, which serves as a windscreen, so the entire stove resembles the top of an hourglass. They also attached stakes to lock the base into the ground. Finally, they made sure the stove could be built with hand tools and accommodate the various pot sizes used in Darfur.
The result? A multipot, multifuel, high-performance stove that is stable from tipping and has good performance in 6 mph crosswinds. It reduces fuel consumption by up to 75 percent, giving the refugees more time, money, and peace of mind. “What looks like a little stove is actually 1,000 dollars in the hands of a refugee family, and a tremendous relief, or reduction at least, from the threat of rape and violence; and maybe some spare time,” he says.
Three years of work went into those pieces of bent metal, and the project is only one-third complete. He still needs to build workshops in Darfur, distribute the stoves, and create a feedback mechanism to see what changes are needed on the current model. “Every product engineer knows that the first run is the trial run,” Gadgil says.
Distributing the stoves isn’t as simple as just handing them out. Gadgil and the Darfur Stoves Team plan to sell each stove for $20. The team don’t want anyone to be denied the stoves from lack of money, but they also don’t want the refugees to become beggars. “If the refugees buy them, then the whole setup [has] a responsibility that the stoves have to be sellable. If they start producing junk, then the refugees stop buying.”
Despite the work ahead, Gadgil is happy with what he has accomplished so far. “We already were twice as good as three-stone fires just with the Tara stove,” he says. “The goal was to get twice as good as Tara itself, which means four times as good as the three-stone fire, and that’s what we accomplished.”