In the small but fanatical world of stovemakers, Peter Scott is something of a celebrity. For the past seven years, under the auspices of the German aid agency GTZ, Scott has designed or built some four hundred thousand stoves in thirteen African countries. He has made them out of mud, brick, sheet metal, clay, ceramic, and discarded oil drums. He has made them in villages without electricity or liquid fuel, where meals are still cooked over open fires, and where smoke is the sixth leading cause of premature death. In the places where Scott works, a good stove can save your life. Scott and Dale Andreatta were in Cottage Grove, Oregon, in early August, to attend Stove Camp, a weeklong event hosted by the Aprovecho Research Center—the engineering offshoot of a local institute and education center and environmental collective. Now in its tenth year, the camp had become a kind of hippie Manhattan Project. It brought together the best minds in the field to solve a single, intractable problem: How do you build cheap, durable, clean-burning stoves for three-billion people? About half the world’s population cooks with gas, oil, or electricity, while the other half burns wood, dung, coal, or other solid fuels. As global temperatures have risen, the smoke from Third World kitchens has been upgraded from a local to a universal threat. The average cooking fire produces about as much carbon dioxide as a car, and a great deal more soot, or black carbon. Cleaning up these emissions may be the fastest, cheapest way to cool the planet. In June, the Waxman-Markey climate bill was passed by the House of Representatives. Hidden among its pages was a short section calling on the E.P.A. to identify ways to provide stoves to twenty million households in five years. Scott had come to Stove Camp to build a better injera stove. For the past several months, Scott and Andreatta had been collaborating on a prototype. Mentions Dean Still, the head of the Aprovecho Research Center. After Still arrived at Aprovecho, in 1989, he worked with a local inventor, Larry Winiarski, to create rocket stoves. By 2004, Still had received grants to tests stoves in other programs. Early in October, Still and the writer flew to Guatemala to visit a study in San Lorenzo, led by Kirk Smith, which tracked more than five hundred local families, some of whom cook with open fires and others who cook with plancha stoves with chimneys. Mentions Angela Jiménez. Smith had data on half a dozen diseases, including pneumonia, that a decent stove could help prevent. The hard part is convincing local villagers, who tend to see the smoke as more of an annoyance than a threat.