Biogas Uses
The main use of the gas from the small domestic plants used widely in Nepal, India
and China, is for cooking. Biogas from cattle dung or food wastes can replace other
cooking fuels, such as wood, LPG and kerosene.
Biogas, because it is mixed with carbon dioxide, has a reduced heating value and
Wobbe number than natural gas. Natural gas burners can be used with biogas, but only
if they are adapted first. Burners can be, and have been, designed for use with biogas.
Information on the design of biogas burners is available in a short course.
Biogas can also be used in engines, if there is sufficient gas. A dual-fuel engine
uses diesel or biodiesel to provide ignition in a compression ignition engine, which
biogas fed in through the air inlet can replace 80% of the fuel. A gas engine uses
the high compression of a diesel engine, but uses a spark to ignite the gas.
The shaft power from the engine can be used to drive machinery, such as an irrigation
pump, or it can be used to drive a generator for electricity.
