Annual Danish informative inventory report to UNECE. Emission ...

tion, such as cumulated mileage driven, engine and exhaust after treatment
maintenance levels and driving behaviour.
Therefore, in order to represent the Danish fleet and to support average
national emission estimates, emission factors must be chosen which derive
from numerous emissions measurements, using a broad range of
real world driving patterns and a sufficient number of test vehicles. It is
similar important to have separate fuel use and emission data for coldstart
emission calculations and gasoline evaporation (hydrocarbons).
For heavy-duty vehicles (trucks and buses), the emission limits are
given in g pr kWh and the measurements are carried out for engines in
a test bench, using the EU ESC (European Stationary Cycle) and ETC
(European Transient Cycle) test cycles, depending on the Euro norm
and exhaust gas after-treatment system installed. A description of the
test cycles is given by Nørgaard and Hansen, 2004). Measurement results
in g pr kWh from emission approval tests cannot be directly used
for inventory work. Instead, emission factors used for national estimates
must be transformed into g pr km, and derived from a sufficient
number of measurements which represent the different vehicle size
classes, Euro engine levels and real world variations in driving behaviour.
In terms of the sulphur content in the fuels used by road transportation
vehicles, the EU directive 2003/17/EF describes the fuel quality standards
agreed by the EU. In Denmark, the sulphur content in gasoline
and diesel was reduced to 10 ppm in 2005, by means of a fuel tax reduction
for fuels with 10 ppm sulphur contents.
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