Emission reduction potential of household biogas plants in developing countries: The case of central Vietnam

Abstract This study involved a systematic analysis of greenhouse gas (GHG) emissions from household biogas plants in Vietnam to determine the emission reduction potential of a typical household biogas plant with a volume of 6 m3 and an assumed life cycle of 20 years. The CO2 emissions pertaining to different phases of the life cycle of household biogas plants were determined by estimating the direct emission of CO2 due to fuel combustion and the embodied indirect emissions of CO2 from materials and services. Among the different life cycle phases, the construction phase corresponded to the maximum emission (79.41%). Further, the CO2 emission reduction potential of a household biogas plant was determined. The results showed that an emission of 0.95 annual tons of CO2 could be avoided via energy substitution. It was also determined that the use of biogas led to a 20% reduction in GHG emissions compared with GHG emissions due to firewood. Moreover, GHG emissions of 384.1 kg CO2-eq·y−1 per animal could be prevented.