Utkilen A/S to make major propulsion upgrades to two vessels

Photo: Wil Weijsters

Bergen, Norway-headquartered Utkilen AS is to make major propulsion upgrades to two of its ice classed vessels using a retrofit solution developed by Brunvoll hydrodynamicists and service specialists that is designed to deliver large savings in fuel and emissions throughout the vessels’ remaining lifetimes.

The two vessels, the 2011-built 9,597 dwt Golfstraum and the 2012-built, 9,595 dwt Rystraum, will receive substantial Brunvoll upgrades by that include a new gear transition, overhaul, and a redesign of propeller blades. Final selection of optimized propeller revolution speed and blade design has been subject to an extensive analysis by Brunvoll in cooperation with Becker Marine Systems, which is supplying its Mewis Ducts for both vessels.

“At Utkilen, we are committed to decarbonizing our fleet,” says Utkilen project manager Carl Ove Utkilen. A crucial aspect of our decarbonization strategy is to maximize the energy efficiency of our vessels, thereby reducing our future dependence on alternative fuels, which require substantial green energy to produce. Our current focus is on identifying and implementing energy-saving devices and technologies across our fleet, while closely monitoring developments in the alternative fuel and propulsion sectors.”

“For our vessels Golfstraum and Rystraum we have collaborated with Brunvoll to redesign our propellers and gears,” he continued. “Additionally, we will be installing Becker Mewis Ducts on these vessels, provided by Becker Marine Services. This simultaneous design process for the propeller and the waterflow towards the propeller, achieved through the cooperation of all parties, has demonstrated higher overall savings in our simulations compared to designing them separately. We are enthusiastic about this project and anticipate significant fuel consumption savings following the installation.”

As part of the retrofit, the vessels will have a reduction in ice class and a new optimized vessel speed. Combined, the changed operating service speed, the reduction gear upgrade, and the redesigned propeller blades with new inflow have a larger emission saving potential than what each upgrade could have provided separately. In other words, says Brunvoll, “2+2 is more than 4 in this case.” This better total is a result of continuous optimized water flow towards the redesigned propeller blades.

Brunvoll and Becker have cooperated closely and performed several rounds of iteration to reach the final design.

The propulsion upgrades are set to take place during the autumn of 2024 and spring of 2025. Brunvoll will take lead on the upgrade process for both vessels, and according to Mads Egseth Melbø, who is sales manager retrofit in Brunvoll, it will be a huge undertaking.

“We will open the vessel up from the side to do a larger gear overhaul and change of gear ratio,” he says. “Thereafter, the propeller improvements will take place. We look forward to seeing the upgraded vessels in action and are excited to follow up with Utkilen on operational results.”