Nepal SEEDS integrates composting toilets with biogas to simultaneously improve sanitation, health, and the environment. A biogas system converts animal and human waste into methane gas that is used as cooking fuel. The system includes a composting toilet, a waste intake, an underground methane fermentation tank, and a piping system that brings the fuel directly into the kitchen.

The environmental benefit is significant. With the addition of biogas fuel, households reduce by 70% their use of wood for cooking which helps regenerate forests and protect wildlife habitats. Health benefits include lessening exposure to infectious diseases through the safe disposal of human waste and reducing indoor air pollution generated by using wood for cooking. Because food preparation and childcare are mainly female responsibilities, women and children benefit most from improving indoor air quality.