GHG emission factors developed for the collection, transport and landfilling of municipal waste in South African municipalities

Abstract

Greenhouse gas (GHG) emission factors are used with increased frequency for the accounting and reporting of GHG from waste management. However, these factors have been calculated for developed countries of the Northern Hemisphere and are lacking for developing countries. This paper shows how such factors have been developed for the collection, transport and landfilling of municipal waste in South Africa. As such it presents a model on how international results and methodology can be adapted and used to calculate country-specific GHG emission factors from waste. For the collection and transport of municipal waste in South Africa, the average diesel consumption is around 5dm3 (litres) per tonne of wet waste and the associated GHG emissions are about 15kgCO2equivalents (CO2e). Depending on the type of landfill, the GHG emissions from the landfilling of waste have been calculated to range from −145 to 1016kgCO2e per tonne of wet waste, when taking into account carbon storage, and from 441 to 2532kgCO2e per tonne of wet waste, when carbon storage is left out. The highest emission factor per unit of wet waste is for landfill sites without landfill gas collection and these are the dominant waste disposal facilities in South Africa. However, cash strapped municipalities in Africa and the developing world will not be able to significantly upgrade these sites and reduce their GHG burdens if there is no equivalent replacement of the Clean Development Mechanism (CDM) resulting from the Kyoto agreement. Other low cost avenues need to be investigated to suit local conditions, in particular landfill covers which enhance methane oxidation.