Propeller blade upgrade cuts Stena Danica fuel consumption

Propeller blade upgrade cuts Stena Danica fuel consumption

Berg Propulsion

The new propeller blades have eliminated the ship’s persistent issue with cavitaion

A replacement propeller blade for Stena Line’s Stena Danica installed by Berg Propulsion has reduced the fuel consumption and machinery vibrations for the Baltic Sea ferry.

Stena Danica entered service in 1983 and sails between the port of Gothenburg, Sweden, and Frederikshavn, Denmark. In 2021, Stena Line contracted Berg Propulsion to replace the ship’s twin propeller blades, with the aim of removing a persistent issue with cavitation, a phenomenon in which vapour bubbles are formed within the water as it passes through the propellers, causing erosion of the blades, additional noise and vibrations, and reduced efficiency.

“Stena continuously reviews the performance of its ships to evaluate whether machinery and systems on board are optimal for their actual operations,” said Per Wimby, senior naval architect at Stena Teknik. “This is actually the third propeller blade replacement undertaken on Stena Danica over the years but this one is especially timely, given that it anticipates new regulatory requirements for all ships to demonstrate their energy efficiency.”

Berg’s replacement blades were reverse engineered to fit the existing propeller hub, which was originally manufactured by another company. It also designed the blades to reflect a planned reduction in the ship’s operating speeds, compromising between one engine or the maximum two engines running per shaft. After several months of operation, Stena has confirmed that the new blades have reduced average fuel consumption while neutralising the issue with vibrations.

“With fuel consumption so high on the agenda, we are putting all available tools at the disposal of our owner clients to secure the efficiencies they need,” said Magnus Thorén, energy and efficiency account manager at Berg Propulsion. “That means delivering tailor-made solutions for specific ship operating profiles, but this project also demonstrates what’s possible using the existing propeller hub: our designers and shipyard project teams could do this for any hub.”

Share this story

Alex Smith
By Alex Smith
12 October 2022

Theme picker