ADAPTATION OF IPCC DEFAULT VALUES ON NATIONAL LANDFILL CONDITIONS

Over the next 10 to 30 years methane emissions from landfills in Germany will continue to represent a major source of greenhouse-gas emissions in the waste sector. Methane emissions have been estimated for the National Inventory Report on the German Greenhouse Gas Inventory (NIR) using the First Order Decay (FOD) method and the IPCC Guidelines for National Greenhouse Gas Inventories. Both national data and default factors (standard values) provided by the IPCC were used in calculating the estimations. A review of the methodological basis and input data used to determine methane formation in landfills indicates that the previous approaches adopted in the NIR reports led to methane formation rates that clearly exceeded actual emissions from German landfills. Both the state of knowledge and the results of investigations focussed on landfill gas production and emissions from numerous German municipal solid waste landfills confirm the latter. To obtain a more accurate description of the methane generation potential and methane generation in landfills, DOC parameters, fraction of degradable organic carbon (DOC f ), half-life and methane correction factor (MCF) can be adapted for the individual organic fractions of waste. When the adapted values for use in the estimation of methane emissions of German landfills are applied, the results yielded are in a range of approx. 50ϼompared to the estimated values reported in the German NIR to date.