This summer, three Duke students helped turn cow dung into a source of cooking fuel for families in rural India.

The students -- Karan Chhabra, Katie Swails and Sandeep Prasanna -- have been working in and around the SAI Sanctuary nature preserve in southern India for their DukeEngage independent study project.

In collaboration with local residents, Chhabra, Swails and Prasanna built a biogas plant. The plant captures methane gas, which can be used for cooking, released by cow dung. It also produces a nitrogen-enriched slurry that can be used as a fertilizer.

The aim of the biogas plant is to provide an alternative cooking fuel to kerosene, which is relatively expensive, and wood, which can harm forests and the health of family members cooking in the kitchen. Electricity is not an ideal source of power either because it is unreliable in the area.

Watch the video above to see the construction of the biogas plant. Learn more about the students' experiences at SAI Sanctuary on their Jungle Blog.