DANISH EMISSION INVENTORIES FOR ROAD TRANSPORT ...

Tonnes
emission-efficient EURO II, III and IV private cars (introduced in 1997, 2001
and 2006, respectively).
In the case of NOx, the real traffic emissions for heavy duty vehicles do not
follow the reductions as intended by the EU emission legislation. This is due
to the so-called engine cycle-beating effect. Outside the legislative test cycle
stationary measurement points, the electronic engine control for heavy duty
Euro II and III engines switches to a fuel efficient engine running mode, thus
leading to increasing NOx emissions (Figure 3.62).
Exhaust particulate emissions from road transportation vehicles are well below
PM2.5. The emissions from light- and heavy-duty vehicles significantly
decreased since the mid-1990s due to gradually stricter EURO emission
standards. The environmental benefit of introducing diesel private cars with
lower particulate emissions since 1990 was more than outbalanced by an increase
in sales of new vehicles in recent years (Figure 6.23).
An undesirable environmental side effect of the introduction of catalyst cars
is the increase in the emissions of NH3 from the first two generations of catalyst
cars (Euro I and II) compared to conventional cars. The emission factors
for later catalytic converter technologies are considerably lower than the
ones for Euro I and II, thus causing the emissions to decrease from 2001 onwards
(Figure 6.27).
The 2010 emission shares for heavy-duty vehicles, passenger cars, light-duty
vehicles and 2-wheelers for NOx (52, 35, 13 and 0 %), NMVOC (5, 58, 8 and
18 %), CO (6, 77, 7, 10 %), PM (25, 37, 35 and 3 %) and NH3 (1, 96, 3 and 0 %),
are also shown in Figure 6.28.
70000
60000
50000
40000
30000
20000
10000
0
1985
1987
1989
1991
1993
1995
1997
1999
2001
2003
2005
2007
2009
Passenger cars Light duty vehicles
Heavy duty vehicles 2-wheelers
Figure 6.23 NOX emissions (tonnes) per vehicle type for road transport 1985-2010.
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