In the late 1800s, Rudolf Diesel himself envisioned a future in which farmers used everyday crops — notably peanuts — to fuel machines. Environmentalists have long touted the benefits of fuels made from renewable organic matter. These “biofuels” often burn cleaner than petroleum and could, if used extensively, push back the day when the world runs out of oil. The most familiar is “gasohol,” gasoline blended with alcohol made from crops like corn or sugar cane.
In India, people who want alternative fuel collect cow dung in a backyard box called a “digester” — made of bricks and concrete or steel or even rubber — and add water. Over time organic processes will produce gas. As pressure builds up in the digester, the gas can be piped into a home for cooking. Biogas experts say three cattle will generate enough gas to cook for a family of five. Larger models can produce enough gas to run a motor to pump water or generate electricity.
Indians are accustomed to burning dried cow dung as a fuel, and digesters are common in some areas, but high oil prices have given the idea of dung power new urgency.
Oil may be growing harder to find, but as K.C. Khandelwal, an adviser at the Ministry of Non-Conventional Energy Sources in New Delhi, notes, “dung is always available.”