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It is assumed that the train is completely electrified. The total emission is roughly
three times higher for truck than for train. During truck transportation, the main
emission of almost 80% takes place during the operation process. For the electrified
train, 100% of the emissions take place during the well-to-tank process.
The main form of energy provision for the different transport modes are:
• Road: diesel fuel.
• Rail: electricity and diesel fuel.
• Sea
−
inland waterways: diesel.
• Sea
−
ocean ships: heavy fuel oil, marine diesel oil, marine gas oil.
• Air: kerosene.
In order to calculate the emission of a supply chain several factors have to be taken
into consideration:
• Type of vehicle/vessel.
• Total weight of the freight.
• Transport distance.
• Utilisation of the capacity.
• Specification of the cargo.
The type of vehicle could be a small or large truck with different EURO emission
classes 1-6 or different types of ships. There are mainly two restrictions in the capacity:
weight and volume. In addition, the proportion of empty trips has to be considered.
Container ships from China to Europe might have high capacity utilisation, from
Europe to China less load is transported and so the capacity utilisation is lower. This can
be expressed by a load factor or the proportion of empty trips. Driving conditions like
number of stops and acceleration and traffic routes like the condition of the road are also
parameters. The most important parameters for logistics are the vehicle type, the type of
the goods, the weight, the capacity unitisation and the distance.
Capacity utilisation
The load factor LF is the mass of the fright
M
divided by the payload capacity
CP
LF
=
M
/
CP
(6.2)
The load factor is a percentage value expressed in net tonnes/tonne capacity.
Another factor of the capacity utilisation is the empty trip factor
ET
. There, the distance
of the empty carrier
DE
is divided by the distance of the carrier loaded
DL
.
ET
=
DE
/
DL
(6.3)
The capacity utilisation
CU
is then given as:
CU
=
LF
/ (1 +
ET
)
(6.4)
Example 3:
A 40 t truck has a payload capacity of 26 t. Consumer goods with a total weight of 12
t are transported fromHamburg to Dresden. FromDresden to Hamburg electronical goods
of 12 t are transported. Statistics from the last year shows that the truck made this transport
route 104 times fromHamburg to Dresden and vice versa. 30 times the truck has to go back
to Hamburg empty. The load factor is in this case 46%. The empty trip factor is: