Report - DCE - Nationalt Center for Miljø og Energi

factors are listed in Annex 2.B.4. For EU emission levels not represented by
actual data, the emission factors are scaled according to the reduction factors
given in Annex 2.B.5.
The fuel consumption and emission factors used in the Danish inventory
come from the COPERT IV model. The source for these data is various
European measurement programmes. In general the COPERT data are transformed
into trip-speed dependent fuel consumption and emission factors for
all vehicle categories and layers.
For passenger cars, real measurement results are behind the emission factors
for Euro 1-4 vehicles, and those earlier. For light duty trucks the measurements
represent Euro 1 and prior vehicle technologies. For mopeds and motorcycles,
updated fuel consumption and emission figures are behind the
conventional and Euro 1-3 technologies.
In order to account for the trend towards more fuel efficient vehicles being
sold in Denmark in the later years, fuel consumption factors for Euro 5 and
Euro 6 passenger cars are estimated in the following way.
An aggregated CO2 emission factor (g/km) for new registered passenger
cars in the years 2009 and 2010 have been calculated from 1) type approval
fuel economy values incorporated in the DTU Transport fleet and mileage
statistics and 2) fuel specific CO2 emission factors. The aggregated CO2 emission
factor for 2010 is used in combination with the overall EU target of 130
g CO2/km in 2015 and 95 g CO2/km in 2020 in order to calculate an interpolated
time series of type approval related CO2 emission factors for the years
2011-2014 and 2016-2019 (year specific CO2 emission factors).
By assuming that the fuel type/engine size specific COPERT IV fuel consumption
factors for Euro 4 cars relate to cars from 2009, Euro 5 and 6
COPERT corresponding factors for each fuel type/engine size combination
are calculated for each year in the forecast period by multiplying the Euro 4
factor with the ratio between the year specific aggregated CO2 emission factor
and the aggregated CO2 emission factor for 2009.
The experimental basis for heavy-duty trucks and buses is computer simulated
emission factors for Euro 0-V engines.
In COPERT IV updated emission factors have recently been made available
for Euro V heavy duty vehicles using EGR and SCR exhaust emission aftertreatment
systems, respectively. The estimated new sales of Euro V diesel
trucks equipped with EGR and SCR during the 2006-2010 time periods has
been examined by Hjelgaard and Winther (2011). These inventory fleet data
are used in the Danish inventory to calculate weighted emission factors for
Euro V trucks in different size categories.
During the 2000’s urban environmental zones have been established in Danish
cities in order to bring down the particulate emissions from diesel fuelled
heavy duty vehicles. Driving in these environmental zones prescribe the use
of diesel particulate filters. The Danish EPA has provided the estimated
number of Euro I-III urban buses and Euro II-III trucks and tourist buses
which have been retrofitted with filters during the 2000’s. These retrofit data
are included in the Danish inventory by assuming that particulate emissions
are lowered by 80 % compared with the emissions from the same Euro technology
with no filter installed (Winther, 2011).