The trim of a vessel is defined as the difference in draught fore and aft. The trimming of a vessel changes the hull resistance, and therefore has an impact on fuel consumption. Every vessel type has an optimum trim that differs according to draught and speed.The trim of a vessel can be changed by shifting ballast water, and to a certain degree, by loading the vessel differently.
WHAT DOES CLIPPER DO?
Clipper has initiated trim tests for a number of our vessel types. The optimal trim of a vessel type cannot be readily predicted. Therefore we have to test every type individually.
The vessels are tested in the towing tank at FORCE Technology in Lyngby, Copenhagen. The results are documented in a software tool, which port captains and crew use in order to find the optimum trim at a given speed and draught.
"Our last optimizing was really visible. Just on change of trim, speed immediately improved by approx. 0.3-0.4 knots with the same pitch settings (main engine load),” Captain Mikhail Sokolov, CEC Copenhagen commented after a voyage in October 2011.
Clipper has achieved considerable fuel savings through trim optimization. Since 2011, more than 20 vessels have been tested, resulting in a savings potential of more than 1600 mt fuel and 5000 mt CO2 per year. And more vessels will be optimized in the future.