Emissions from ships in port
Summary and conclusions
The present report is prepared in order to determine the magnitude of emissions from ships in three Danish ports and for the entire country.
Based on two international reports about ship emissions and on Danish publications about this matter as well as discussions with relevant experts comprehensive information about the traffic handled by three selected Danish ports has been gathered. A number of assumptions concerning motor size, energy consumption and duration of stay in port for different types of ships have been made.
Auxiliary engines on board ships are main contributors to the total emissions. The equation used for calculating the emissions from ships consists of five terms each having an uncertainty. The total uncertainty is estimated to be less than 100%.
The investigation shows that the Port of Copenhagen has the largest absolute emissions. The main contributors to the emission of NOx are ferries alongside quay (25%), unloading of tankers (23%) and cruise ships alongside quay (18%).
Manoeuvring of ships within the port accounts for 15% of the total emission of NOx.
The Port of Køge is handling a relatively smaller number of tankers than the port of Copenhagen. The main contributor to the emission of NOx is therefore other bulk carriers alongside quay (49%).
In the Port of Elsinore manoeuvring of ships accounts for about 73% of the total emission of NOx. The mean time for manoeuvring is about 6 minutes and the mean time for staying alongside quay is about 10 minutes for each in-coming ship.
Ferries in regular operation featured by short stays in port – as in the case of Elsinore – are not able to make use of land-based electricity supply.
However, in the Port of Køge electricity supply is available to ships from outlets placed at the quay. Only few ships take advantage of this possibility. The study shows that an essential part of the emissions can be transferred from the port to the power stations provided a higher utilisation of electricity from outlets placed in the port.
The Port of Copenhagen presents a potential for a large-scale relative reduction of emissions. Emissions of NOx from cruise ships and ferries alongside quay account for about 43% of the total emission of NOx.
The total emissions from the three selected ports are shown in the table below.
Port |
Electricity |
Tons, year 2001 |
|||||
NOx |
CO |
Hydro- |
CO2 |
SO2 |
Partic- les |
||
Copenhagen |
49.000 |
560 |
140 |
24 |
29.000 |
130 |
14 |
Elsinore |
13.000 |
150 |
58 |
6,5 |
7.800 |
19 |
3,1 |
Køge |
3.100 |
35 |
5,6 |
1,6 |
1.900 |
14 |
0,80 |
Total |
65.100 |
750 |
200 |
32 |
39.000 |
160 |
18 |
In order to estimate the magnitude of emissions from ships in Denmark the emissions from 21 larger ports have been calculated. These ports represent 85% of the total turn-over of goods including 95% of goods in liquid form. Loading and unloading of liquid goods are highly energy consuming processes. The emissions from these ports are shown in the graph below.
