Emission mitigation potentials and costs for non-CO2 greenhouse gases in Annex-I countries according to the GAINS model

摘要

The GAINS model allows for estimation of costs and potentials for greenhouse gas (GHG) mitigation by individual GHGs. In this article, the GAINS model is used to assess mitigation potentials for non-CO_(2) GHGs in 2020 for all countries covered in the Annex-I of the Kyoto protocol. Mitigation measures for methane, nitrous oxide or fluorinated gases and their costs are identified and mitigation potentials and costs are compared with other available studies. Differences in the structure of economic sectors between countries are important determinants for the differences in the respective contribution of non-CO_(2) GHGs. For some countries, a successful application of mitigation options clearly hampers the potential still available for future reductions. While a number of options exist to reduce CO_(2) even at negative costs (～25% of the overall reduction potential), this is not the case for non-CO_(2) gases. Non-CO_(2) gases, however, provide considerable potential in the very low cost range (less than 10 €/t CO_(2)-eq), in particular as they are affected by options to abate CO_(2) as well. In the range for very cheap options, non-CO_(2) gases cover about 36% of the reduction potential, a fraction which is decreasing for the higher cost range, to about 26% for a carbon price of 100 €/t CO_(2)-eq. These figures have been calculated for the total of Annex-I countries, assuming a social discount rate of 4%.