Last year the Maseno School in western Kenya completed a substantial renovation. A major part was a brand new 720-student dormitory, but what the renovation lacked was a new sanitation system; the current one is stinky and is polluting a nearby stream that provides drinking water to a community. Five students from the school came up with a solution: A biowaste tank that would maximize the efficiency of processing excrement, while minimizing pollution and creating biogas as a byproduct. The biogas could be used for cooking instead of the traditional wood fires, which are bad for the forest and the smoke is bad for health.