Marin gas logistics. Work package 5. D5-5 Environmental studies - assessment of air emissions in terminal ports

Transcription

1 Marin gas logistics Work package 5 D5-5 Environmental studies - assessment of air emissions in terminal ports

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3 2 TABLE OF CONTENTS 1. Summary and conclusions Introduction Objectives Operational profile of RORO and ROPAX ships Operational profile ROPAX ship Operational profile RORO ship Power requirement in harbour operation Emission assessment in terminal port Exhaust emissions Port of Lübeck References...10

4 3 1. Summary and conclusions This study is carried out under work package 5 of the Magalog project. In the report an overall assessment of air emissions in terminal ports by using natural gas fuelled ships are studied. Based on general emission data and typical operation profile and fuel consumption of RORO and ROPAX vessels in port, the specific emission reductions potential in port operation are assessed. By substituting conventional fuel with natural gas a significant emission reduction can be achieve as follows: NOx 80% reduction, SOx: 99 % reduction and PM 95% reduction. The reduction potential is due to the combustion properties of natural gas. Assuming a future scenario for market penetration of 25% for gas fuelled ship operating in the terminals and port of Lübeck the potential emission reduction has been calculated as follows: Operation mode NOx-emission SOx emission PM-emissions t/year t/year t/year Emissions per ship, ,6 operation,% 80% 99% 95% operation, t/year, per ship 38,4 21,7 1,5 operation for 15 ships, t/year, total The example shows that gas fuelled ships would have a significant effect in reducing emissions in the terminal and ports they call.

5 4 2. Introduction LNG as fuel for short sea shipping has potentials for significant lower emissions to air. In special, the harmful emissions as nitrogen oxides (NOx), Particles Matter (PM) and Sulphur oxides (SOx), which are considered to have local and regional environmental effects and health effects on human being is reduced with LNG operation compared to operation on conventional fuels. In this report the assessment of the reduction potential for emissions to air from ships in terminal ports by using LNG as fuels are outlined. To estimate the emissions reduction potential in port in a general way it was decided to focus on the Lübeck/Travemünde area, which is one of the busiest port in the Baltic area, and to investigate the effects it may have to convert RORO and ROPAX ships to LNG operation. These ship types are found to be the most feasible candidates for LNG operation for the time being. The work is carried out under Work package 5 (WP 5) of the MAGALOG project 3. Objectives This work package was aimed at analyzing the technical and economical aspect by using LNG as fuel in the Baltic Sea and setting the pace for future LNG supply logistics and logistic infrastructure. The sub-task studied in this report is related to emissions in port, and the environmental effects in terminal ports by using natural gas as fuel.

6 5 4. Operational profile of RORO and ROPAX ships 4.1 Operational profile ROPAX ship Typical operational profile of a ROPAX ships are characterised by high speed and short harbour operation time. Typical operation pattern will be two crossing between North European harbours each day. This operation pattern requires high main engine power to obtain required speed and good manoeuvrability to reduce the total harbour time. A typical operation profile based can be obtained as follows: Table 4.1 Operational profile of typical ROPAX ship, round trip data Based on the operation profile of the ship the fuel consumption is predicted to be 61 ton/day (HFO) for the example Ropax ship. 4.2 Operational profile RORO ship The case ship is characterised by regular operation between harbours in the Baltic and/or North Sea. Typical operation pattern for the case ship will be one roundtrip in 10 days which will be the basis for further benchmarking of the RORO ship. A simplified operation profile can obtained as follows:

7 6 Operation condition Main engine power, kw Aux engine power, kw Time in this mode (hours per roundtrip) % of time on a roundtrip Harbour (Loading/unloading) Manoeuvring Sea going (Transit voyage) (90% of MCR) Table 4.2 Operational profile of the RORO example ship, (LOA 125 m), design requirements, 10 days roundtrip Based on the operation profile of the ship, the fuel consumption is predicted to 22 tons/day, (HFO). 4.3 Power requirement in harbour operation Based on information from ship 1 owners the required power consumption at berth for ROPAX vessels for operation in North European harbours has been estimated. This is summarized in Table 4.3. Average power consumption, aux engines Ship ref kw ROPAX A 3525 ROPAX B 3525 ROPAX C 1750 ROPAX D 2200 ROPAX E 1998 ROPAX F 2004 Average 2500 Table 4.3 Average power consumption at berth for six ROPAX ships Data for RORO ships are somewhat more limited but these ships have in general less power requirements in port. As indicated above, power requirements of 1700 kw for a 125 m RORO ship during loading operation may be assumed. In the Baltic Sea the average RORO ship are somewhat larger and power requirement during in harbour operation is assumed to be 2500 kw. 1 Stena Line, Color Line, DFDS Seaways

8 7 5. Emission assessment in terminal port 5.1 Exhaust emissions Natural gas is an excellent fuel for internal combustion engine. The combustion properties of natural gas make it possible to design gas fuelled engines with high efficiency and low exhaust emissions. Comparison of exhaust emissions of natural gas operation and MDO operation shows the differences in exhaust emissions from the two types of bunker fuel. g/kwh g/kwh MDO 1% S g/kwh MDO 1% S CO2 NOx natural gas MDO 1% S g/kwh 0,3 0,2 0,1 0 natural gas MDO 1% S natural gas Figure 5.1 Specific emissions from ship engines burning MDO or natural gas. 6 0,4 SO2 natural gas Particulates To determine emissions from ships entering and leaving ports as well as at berth, the fuel consumption and the emission factors for the engines and boilers in operation is required. The power requirements when entering a port terminal and at berth in port will vary from one ship type to another, and the aim of this report is not to go into details of the various Baltic and North sea ports. By using previous studies /4/ and back ground information it is possible to assess local emissions in port and to estimate the reduction potential by using LNG as fuel. 5.2 Port of Lübeck Lübeck is one of the ports in the Baltic with the highest frequency of regular RoRo and Ropax traffic. Weekly 85 departures are registered from Lübeck to various ports in the Baltic Sea and close ports in Northern Europe. The routes are handled by 36 different vessels, /1/. Calculated total emissions of ships in the Travemünde and Lübeck area at berth at all quays and of the entire shipping traffic in motion for the year 2003, /4/:

9 8 Emissions to air, tonnes/year Emission Moving traffic Ships at berth Total SO % 5 % 100 % NOX % 31 % 100 CO % 31 % 100 % CO % 31 % 100 % HC % 31 % 100 % VOC % 31 % 100 % Table 5.1 Emission estimate in terminal and port of Travemünde/Lübeck area, 2003 /4/. In general it can be concluded that approximately 70% of the emissions are related to movement of the ships when they approach/leave the terminals and 30% is related to ships at berth. Extracting the data in Table 4.3, and average fuel consumption for one ship of some 450 tonnes/year can be obtained for ships at berth and some 900 tonne/year for moving traffic. Introduction of LNG as fuel may be contribute to reduce the harbour emissions. Assuming a ship design where all engines are gas fuelled, a specific reduction in NOx and particles may be obtained for all operation modes of the ship, i.e. emissions will be reduced in accordance with Figure 5.1. To quantify the emission reduction potential, detailed data of ship harbour operation is required, Such data has not been available, but some calculations have been done on general basis based on input from Table 5.1. This is shown in Table 5.2. Operation mode Fuel consumption Sulphur emission, SOx NOx-emission PM-emissions t/year t/year t/year t/year At berth ,0 5,4 0,4 Manoeuvring/moving ,0 16,7 1,2 Sum ,6 Reduction potential, LNG operation 80% 99% 95% Table 5.2 Estimate of fuel consumption and exhaust emissions in port, average ship type in Lübeck port, MDO/HFO operation (1,5%S). Emission reduction potential with gas operation. Substituting MDO/HFO with LNG NOx-emission may be reduced with 80 % and sulphur emission with 99%. In addition the particles are reduced with 95%.

10 9 This will have significant effect on the air quality in any harbour area, which is visited by gas fuelled ships. Assuming a market penetration of gas fuelled ships of 25%, which operate in regular routes to Lübeck some 15 ships will be gas fuelled. The emission reduction potential for such scenario is indicated in Table 5.3. Operation mode NOx-emission SOx emission PM-emissions t/year t/year t/year Emissions per ship, ,6 operation,% 80% 99% 95% operation, t/year, per ship 38,4 21,7 1,5 operation for 15 ships, t/year, total Table 5.3 Emission reduction potential in Lübeck terminal and port area assuming 15 gas fuelled ships in operation

11 10 6. References /1/ Rogde, T.: Short Sea shipping in Europe. Study of ship and transport volums in the Baltic Sea, the North Sea and on Inland waterways in Europe. MAGALOG WP4 Delivery D4.1 /2/ Stenersen, Jarslby: D4-2 Economical and Environmental effect of LNG fuelled ships MAGALOG WP4 Delivery D4.2 /3/ Stenersen: D4-3 Analysis of competitive strength of LNG as ship fuel compared to fossil fuels and alternative fuels. /4/ Implementation of Agenda 21 in European Ports at the example of Lübeck-Travemünde, Research report UBA F+E-project: FKZ , Stadtwerke Lübeck GmbH in cooperation with GAUSS, December 2004