Life with our Sisters -- Dung Cakes to Make Cake?

When visiting our sisters the use of cow dung as a form of energy shocked me! As in Rajasthan, India our sisters usually do not use coal or electricity to cook their food, in turn they use cow dung. But HOW?

Balls of cow dung, coined dung cakes, are dried and saved to cook food from. Then, In a concrete cauldron, cow feces and water are mingled. This mixture decomposes in a big tank as it descends. As it decomposes, biogas rises to the tank's top and exits through a pipe. This pipe extends from the tank into the just outside the home and connects to a gas burner. Now our sisters can cook!

Pictured: Gas Burner for Cooking