Popular Mechanics: “An estimated 2.2 million refugees huddle in makeshift camps in the Darfur region of western Sudan. In the camps, they are safe, but they cook their meals over inefficient wood fires, and as already scant forests are depleted they must venture ever farther to gather fuel—up to 9 miles in some cases. When a program officer from the U.S. Agency for International Development asked Ashok Gadgil, a senior scientist at the Lawrence Berkeley National Laboratory in Berkeley, Calif., to help solve the problem, Gadgil recruited LBNL colleague Christina Galitsky, an environmental energy researcher. Together they traveled to Darfur to meet the refugees and learn about their cooking needs. Back at LBNL, they and a team of students developed a high-efficiency cookstove made of in-expensive sheetmetal. There’s nothing high-tech about it—a few pieces of bent metal and a cast-iron grate improve combustion and energy transfer—but it uses 55 to 75 percent less wood than a cooking fire, slashing the time refugees need to spend in heightened danger. The stoves fit local cookware, and shield flames from the region’s strong winds. Each stove costs about $15 and should last about five years. “We have not invented something altogether new,” Gadgil says, “but we have tuned the technology to work with the refugees.””