The Oslo-Headquartered RoRo shipowner Wallenius Wilhelmsen is proceeding with steps on its journey towards zero emissions by upgrading their PCTC vessel “Aniara” with a newly developed 137-tonne, 23-meter bulbous bow.
The bulbous bow was installed at the IMC-Yongyue (IMC-YY) repair yard in Zhoushan, China, where the process was executed within the anticipated three-week dry-docking span.
This bow upgrade is only the first one, as the company states, as the vessels “Oberon”, “Tijuca” and “Tirranna” will also get new bulbous bows installed with the pre-fabrication are already underway for installations for “Tijuca” and “Oberon” to take place later this month.
Adam Larsson, Senior Manager of Energy Efficiency and Performance, said that “The existing bulbous bow design was initially optimized for one very specific draught and speed. However, operational data clearly show that the vessels operate at lower draughts and speeds a significant portion of the time, where the existing design is not performing well, creating additional resistance to move through the water.”
Wallenius Wilhelmsen has teamed up with DSEC & DSME/Hanwha as design partners, and the team made an optimized design that reduces resistance and promises considerable fuel savings.
It is expected that these fuel savings amount to an impressive average of 6%, translating to a reduction of 1,400 tonnes of CO2 annually for a single vessel.
Adam Larsson furthermore said that “We can expect even larger average savings if actual operating speeds are reduced in the future because the new design compared to the old will perform much better at lower speeds. Worth noticing is that at some operating conditions, such as lower draught about 8 m and 14 knots speed, the savings can be as much as up to 30%.”
Lars Ekren, Senior Manager in Newbuilding & Projects, said that “The most exciting part of the project is during the lifting and installation of the new bulbous bow section as it can never be guaranteed that everything will go as planned. Luckily, the new section matched perfectly well with the existing hull, and the yard managed to finalize the installation in less than a week, which is impressive.”
Photo credit: Wallenius Wilhelmsen