Energy related emissions of non-CO2 greenhouse gases and the climate impact of forest residues - a synthesis

This report describes measures to reduce non-CO2 greenhouse gas emissions and estimates CO2 emissions from using forest residues for energy due to impacts on biogenic carbon stocks.

Measures to reduce emissions of methane, nitrous oxide and fluorinated gases have been described and quantified where possible. The measures presented for methane is reduced methane leakage from landfills, leakage from transmission and distribution of natural gas and methane from incomplete combustion. Landfills are currently the second largest source of methane emissions in Sweden and the potential to reduce methane leakage is estimated to be 800 kilotonnes of carbon dioxide equivalents, or more than 60% reduction from present emissions. The potential to reduce methane leakage from natural gas pipelines have not been quantified. It is estimated that methane from incomplete combustion could be almost entirely avoided. For nitrous oxide, two different measures were studied. Nitrous oxide from fluidized beds has a reduction potential estimated to around 20 %. However, a study of the reduction potential in the EU-27 shows significantly higher reduction potential.

Projections of nitrous oxide emissions from road vehicles show increased emissions to 2020 despite measures. The fluorinated gases analysed is HFC leakage from air conditioners and SF6 from switchgears and switchers. The reduction potential is considered high for HFC leakage from AC in vehicles, mainly due to the replacement of HFCs with a high GWP to HFCs with lower climate impact. For sulphur hexafluoride, emission projections show only modest reductions to 2020.