OMIT – Manual for environmental calculation of international freight transport
Enclosure C
Enclosure C.1
RO-RO ferry
Enclosure C.2
Container ship
Enclosure C.3
Bulkcarrier
Enclosure C.4
Ships' average age - energy consumption & emissions
According to the Danish Shipowners' Association, the average age of the different ship types under Danish colours is
| Tramp vessels (not in line service). (Bulk carriers belong to this category): | 11.7 years |
| Cargo vessels in line service (e.g. Container ships and Ro/Ro ships): | 6.2 years |
| Tankers: | 8.0 years |
| Passenger ships/ferries: | 14.6 years |
| Special ships (Offshore vessels, ships for cattle transport etc.): | 11.4 years |
2. Correction of the energy consumption
Based on the average specific oil consumption in 1973 and 1999 of respectively 220 g/kW hour and 170 g/kW hour the additional oil consumption based on 2000 is as follows:
(220 – 170)/170/27 x 100 = 1.09% per year
As all calculation formulas for energy consumption apply for new ships with basis year 2000, we suggest the following correction in percentage, which means that a ship is considered as an in average older ship:
Bulk carriers: 11.7 x 1.09 = 12.8%, i.e. correction factor: 1.128
Container ships and Ro/Ro cargo ships:
6.2 x 1.09 = 6.8%, i.e. correction factor: 1.068
3. Correction of emission factors
In the same period of time there has been hardly any progress as for emissions, which is why only changes in oil consumption specifically have been considered, which indirectly will also result in a correction of the emissions.
The energy consumption data in Enclosure C.1 to C.3 in OMIT are based on Hans Otto Kristensen, equivalent to TEMA2000.