The TROP trim optimisation module, now integrated into Interschalt's MACS3 loading computer system, calculates how the tanks need to be filled to achieve the ideal trim.
"The user can now even automatically determine the best ballast distribution necessary to save the greatest amount of fuel," says software developer Bernhard Finke. The module also takes into account all safety regulations pertaining to stability and strength.
Interschalt claims that by using TROP, a medium-sized container ship transporting some 7,500 TEU at 20 knots could save 2 to 3 per cent on fuel, and thus save in the region of $1,500 to $2,200 a day.
During the 1990s, ship-owners were using models in towing tests designed to determine the trim that produced the lowest resistance as a ship moved through water, notes the company based near Hamburg (Germany). These tests showed that, in many cases, a slightly lower forward draft yielded the ideal trim.
Based on these findings, Interschalt added a ballast-optimisation tool to its MACS3 loading computer system. Over the next 15 years however, interest in the module declined because of the costs of conducting the associated towing tests, says the company.
"These days, towing tests can be realistically and economically simulated with special software," said Mr Finke.
"However, determining the optimum trim is one thing; being able to practically apply these findings in actual ship operation is another."
After a ship has been loaded, the crew usually has only one method left to alter its trim: using the ballast tanks. TROP calculates how to fill the tanks to achieve the ideal trim.