e., oil, gas, coal); TPES is total primary energy supply including fossil fuels, nuclear and renewables; GDP is economic activity; sc is share of net CO2 to CO2 emissions excluding carbon sinks; co is emissions coefficient; sf is share of fossil fuels in the total primary energy supply; and ei is energy intensity. By using the four factors in Eq. (2), the following features can be analyzed for differences in MAC curves. sc The effects of carbon absorption measures

(i.e., the ratio of net CO2 emissions to CO2 emissions from fossil fuels and industry excluding carbon sinks). co CO2 emissions coefficient from fossil fuels (i.e., the ratio of CO2 emissions to the primary energy supply from fossil fuels).

sf The effects of fuel switching on the primary selleck chemical energy supply (i.e., the ratio of fossil fuel consumption to the total primary energy supply). ei The energy intensity (i.e., the amount of total primary energy supply per economic activity). Figure 4 shows the example results of decomposition analyses in Japan, China, India, the US and EU27 in 2030, by using the extended Kaya identity described above. Figure 4a indicates the comparison of “sc” under a certain carbon price with “sc” under the baseline and reflects the effects PSI-7977 clinical trial of changes in the ratio of carbon absorption measures. The more CCS is introduced in the power and industry sectors, the lower “sc” becomes (less than 100 % relative to the baseline). With regard to carbon absorption measures, GCAM consider both CCS in the power and industry sectors and carbon sinks in the LULUCF sector; however, AIM/Enduse[Global], Rolziracetam DNE21+ consider only CCS. It is found in Fig. 4a by comparing GCAM_CCS and GCAM_noCCS that the effects of carbon sinks in the LULUCF sector are estimated to be

small. Therefore, it is more important to focus on the effects of CCS. The number of “sc” by AIM/Enduse and DNE21+ becomes lower than the baseline as the carbon price rises due to the effects of CCS in 2030 to some extent; however, GCAM_CCS estimates a large amount of CCS compared to other models. For example, the GCAM_CCS scenario shows negative emissions due to the effects of introducing biomass power plants with CCS in India in 2030. The amount of CCS is one of the reasons for the large difference in MAC results. Fig. 4 Decomposition of CO2 emissions in some key factors. a The effects of absorption measures. b The CO2 emissions coefficient from fossil fuels. c The effects of fuel switching in primary energy supply.