Women living in the refugee camps of Darfur, Sudan must walk for up to seven hours to collect firewood for cooking, putting them at risk for violent attacks. Alternately, they must sell precious food for fuel. But researchers at Lawrence Berkeley National Laboratory have engineered a more efficient wood-stove, which is greatly reducing the women's need for firewood and the threats against them. This video is part of a series, Engineering Is Saving the World with Cookstoves. Find all of our e-books at kqed.org/ebooks.