K Line subsidiary launches Japan’s first tugboat with onboard biofuel blender

Kawasaki Kisen Kaisha’s (K Line) subsidiary Seagate Corporation, on Wednesday (22 April) launched and named a newly built tugboat, equipped with an onboard biofuel blending system at Kanagawa Dockyard in Japan. 

While it is equipped with a conventional diesel engine propulsion system using marine fuel oil, the tugboat, named Bisan Maru, is the first Japanese tugboat to be equipped with a biofuel blender and an ultrasonic hull anti-fouling system. 

The biofuel blender installed onboard the vessel, which was manufactured by Conhira, is capable of blending marine fuel oil and biofuel at the blending ratio of choice between 0% and 100%. 

“This system paves the way for the stable production of fuel that includes biofuel at the desired blending ratio onboard the vessel, even when the ship is in places where it is difficult for bunkering ships to supply blended biofuel,” K Line said in a statement. 

The ultrasonic hull anti-fouling system uses ultrasonic waves to hinder marine organisms’ adhesion to the hull and mitigate the deterioration of fuel efficiency due to hull fouling. 

This system was developed for a hybrid EV tug scheduled to be completed in 2027. To verify the system in an operational environment, it was first installed in the vessel.

Photo credit: Kawasaki Kisen Kaisha
Published: 24 April, 2026