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Fuel Sulphur Content and Fuel Consumption

2 VESSEL SURVEYS AND SITE VISITS

2.11 Fuel Sulphur Content and Fuel Consumption

Much thought and consultation was required to develop appropriate terminology for the survey form to collect data regarding fuel characteristics. A variety of fuel types are used by the commercial marine industry and different nomenclature may be used for describing similar marine fuels depending on their source. Respondents were asked to classify their fuel used as: Distillate (Light) or Residual (Heavy), and indicate the specific fuel grade, location and sulphur content of the last bunker delivery. When conducting onboard surveys, copies of bunker delivery notes for the last bunker delivery were obtained whenever possible.

A light distillate fuel (MGO, MDO) with low sulphur content (< 0.5%) is used by approximately 50% of the vessels for auxiliary diesel generators and in some cases for the propulsion engine only if operating in a SECA environment. An intermediate fuel (IFO grade 180 cSt), 1-2% sulphur content, is used by a few vessels or blended with light distillate for generator use but the rest of the fleet (approx 50%) will use a heavy fuel oil (IFO/HFO grade 380 cSt) as the preferred type of fuel for the propulsion engine, diesel generators and auxiliary boilers. Steam vessels will use a HFO grade 500 cSt as their fuel for the main boilers. Only one steam vessel was surveyed.

In general it was found that foreign vessels that operate only partly in Canadian waters purchase as little fuel as possible in Canada, and in some cases are able to completely avoid the Canadian marine fuel market. This was at first believed to be because Canadian marine fuel has lower sulphur content and is sold at a higher price than some other sources of marine fuels. However, analysis of the data collected did not confirm this.

For vessels that operate 90% or more of their time in Canadian waters, average fuel sulphur levels were reported to be 0.53% Sulphur for light (distillate) type fuels, and 2.53% Sulphur for heavy (residual) type fuels. For vessels operating less than 90% of their time in Canadian waters, average fuel sulphur levels were reported to be 0.77% for light (distillate) type fuels, and 2.5% for heavy (residual) type fuels.

The data was then looked at to see if there was a difference between vessels with and without an IMO International Air Pollution Prevention (IAPP) certificate. For vessels claiming to have an IAPP certificate, average fuel sulphur levels were reported to be 0.69% for light (distillate) type fuels, and 2.45% for heavy (residual) type fuels. For vessels without an IAPP certificate, average fuel sulphur levels were reported to be 0.61% for light (distillate) type fuels, and 2.21% for heavy (residual) type fuels, indicating no significant difference.

There was no apparent difference in fuel sulphur based on area of operation (e.g. international or domestic), or based on vessel status with respect to IMO IAPP certification. Except for very regional

operations, such as passenger ferries, tugs and other harbour vessels, it cannot be assumed that a vessel will be using fuel that was embarked in any particular area. Based on the limited data from this survey, it is recommended that available worldwide averages for fuel sulphur by fuel type be used for the emissions inventory and forecast.

Based on all surveys from this study, for commercial marine vessels average sulphur for light (distillate) marine fuels was 0.66% and average sulphur for residual marine fuels was 2.42%, for vessels operating in the EC/GL region. It is important to note that the assumptions for fuel sulphur that were used in the 2006 study have not been changed in the Tool and for the inventory calculations presented in this report.

As described in section 4 of this report, it would be straightforward to use the revised Tool to calculate the impact of changing the fuel sulphur assumptions.

Naval vessels use only one grade of fuel procured to a Canadian General Standards Board Specification.

Information obtained from the Department of National Defence indicates that fuel sulphur for naval fuels in 2006 was less than 0.2%, and often was within the limit for ultra-low sulphur fuel at less than 15 parts per million (ppm) sulphur. New sulphur limits for marine diesel in Canada came into effect in June 2007, which limit sulphur content to 500 ppm maximum. This change can be expected to impact the emissions from vessels that operate exclusively in Canadian waters and procure fuel in the domestic marine fuel market. The survey data on fuel sulphur content is summarized in Table 2-9.

Table 2-9: Fuel Sulphur Content by Vessel Class

Distillate Residual

INNAV Vessel Class Range of Sulphur

2.11.2 Fuel Consumption

The survey form requested that respondents indicate the average fuel consumption in metric tonnes per day for both light (distillate) fuels and heavy (residual) fuels. It was interesting to note that where both a vessel and its Company provided separate survey data, the number provided by the vessels for fuel consumption per day was often considerably different than figures offered by their company. There was also very wide variety in the fuel consumptions reported within one vessel class, and many survey forms were incomplete for fuel consumption unless the survey was completed by WME through an on-site vessel visit. The survey data for fuel consumption is available in the database, although it is not used directly in the Tool for emissions calculations. Due to the high variability in the data reported, and the implications of fuel switching, the fuel consumption data is not considered very useful. The average fuel consumption reported by vessel class is shown in Table 2-10.

Table 2-10: Average Fuel Consumption by Vessel Class INNAV Vessel Class