En model for godstransportens udvikling - DCE - Nationalt Center for ...

The reason for choosing between imports and exports and the use of
Danish fuel is that the international accounts for fuel use is based on
the fuel sold in the different countries and not on the fuel used in the
countries. Hence, the implicit assumption in these accounts is that the
fuel sold to foreign vehicles in Denmark equals the fuel bought by
Danish vehicles abroad.
To calculate the traffic performance the same line of calculations as
for the national transports are carried out. The linking technological
coefficients are all estimated using trends.
A further assumption used for the international transport is that the
average load on the vehicles is the same as the national average load
on the largest vehicles. This is an assumption which seems reasonable,
but which is unverifiable (the data-sets do not contain any information
on the number of trips etc.).
It is evident from the assumptions that the calculations on international
transport are very uncertain. The reason for including these
transports is only to demonstrate an indication of the development in
these transports. The absolute levels should be used with caution.
Emissions
Many things influence the emissions from transport in heavy vehicles.
The split on the size of the vehicles is only one of these. We have
included information on the age of the vehicles, the year of production,
the average utilisation rate and the average annual number of
km a vehicles run. Besides these factors also the weather, the geographical
area (urban, non-urban) etc. influence emissions. It is not
possible to include all these elements in a model like the one we have
developed. Instead we have used the above-mentioned information
to calculate average emission factors. However, we have included
regulation on the amount of emissions of different substances set by
the EU.
Examples from the use of the model
The basis for all the examples given in the report is an economic forecast
made by the Department of Finance using the national macroeconomic
model ADAM covering the period 1999 to 2010. The model
has then been used to calculate the consequences of this economic
forecast. Together with the economic forecast the satellite model
EMMA has been used to calculate similar consequences as the calculations
from our model.
The result of the model predicts quite large increases in the traffic
performance, especially for the largest vehicles. However, the increase
does seem to be somewhat overestimated. In some cases the
overall trend is not found. This is especially the case for the small
company-owned vehicles.
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