Greenhouse implications of household stoves: An analysis for India

It is commonly assumed that biomass fuel cycles based on renewable harvesti ng of wood or agricultural wastes are greenhouse-gas (GHG) neutral because the combusted carbon in the form of CO2 is soon taken up by regrowing veget ation. Thus, the two fifths or more of the world's households relying on su ch fuels are generally not thought to play a significant role in GHG emissi ons, except where the wood or other biomass they use is not harvested renew ably. This review examines this assumption using an emissions database of C O2, CO, CH4, NMHC, N2O, and total suspended particulate emissions from a ra nge of household stoves in common use in India using six biomass fuels, ker osene, liquefied petroleum gas, and biogas. Because typical biomass stoves are thermally inefficient and divert substantial fuel carbon to products of incomplete combustion, their global warming commitment (GWC) per meal is h igh. Depending on time horizons and which GHGs are measured, the GWC of a m eal cooked on a biomass stove can actually exceed that of the fossil fuels, even if based on renewably harvested fuel. Biogas, being based on a renewa ble fuel and, because it is a gas, being combusted with high efficiency in simple devices, has by far the lowest GWC emitted at the stove per meal and is indicative of the advantage that upgraded fuels made from biomass have in moving toward sustainable development goals. There are a number of polic y implications of this work, including revelation of a range of win-win opp ortunities for international investment in rural energy development that wo uld achieve cost-effective GHG reduction as well as substantial local benef its.