Energy-saving PBCF Reaches Milestone Orders Received for 3,500 Vessels

Achieves 3%-5% Reduction in Fuel Consumption, Helping in-service Vessels Comply with Future Fuel Efficiency Regulation

Tokyo - December 09, 2020

Mitsui O.S.K. Lines, Ltd. (MOL; President & CEO: Junichiro Ikeda) today announced that Propeller Boss Cap Fins (PBCF), marketed by its group company MOL Techno-Trade, Ltd. (MOL Tech; President Hirokazu Hatta; Headquarters: Chuo-ku, Tokyo) has now been ordered for 3,500 vessels.

PBCF is an energy-saving device attached to the propeller of a vessel. It breaks up the hub vortex generated behind the rotating propeller, resulting in energy savings of 3% to 5% compared to an identical vessel not equipped with PBCF. Higher fuel efficiency in turn cuts emissions of greenhouse gases (GHGs), reducing the shipping industry's environmental impact.

PBCF was co-developed by MOL, West Japan Fluid Engineering Laboratory Co., Ltd., and Mikado Propeller Co., Ltd. (now Nakashima Propeller Co., Ltd.), and introduced in 1987. PBCF has been installed mainly by Japanese Shipowners, and in 2006, orders reached 1,000. As overseas shipowners and ship operators widely recognized the value of PBCF on the back of skyrocketing bunker prices and growing worldwide awareness of the need for CO2 reduction, the number of orders reached 2,000 vessels in 2011 and topped 3,000 in 2015. MOL Tech calculated that the widening use of PBCF has contributed to a cumulative 42 million-ton reduction in CO2 emissions Worldwide.

In 2017, MOL Tech, MOL, and Akishima Laboratories (Mitsui Zosen) Inc. jointly developed a new type of PBCF, featuring a refined fin shape and height to further enhance its energy-saving effect. This upgraded PBCF has already been installed on over 300 vessels. Furthermore, the development team has moved forward with research on a hybrid version with other energy-saving devices such as the Pre Swirl Fin and Energy-saving Rudder with Bulb Fins, and confirmed synergetic effects in a model test (Smart Wake Ship style), having similar wake flow to a full-scale ship. In these ways, PBCF continues to evolve every day.


Hybrid test with other energy-saving devices. Image by MOL.


PBCF installed on a propeller (circled in red). Image by MOL.

PBCF won the Award for Logistics Environmental Impact-Reducing Technology Development in the 21st Logistics Environment Award (Note 1), as selected by the Japan Association for Logistics and Transport. It is recognized as an environment-friendly device all over the world, helping to reduce the shipping industry’s environmental impact.

Effective January 2023, the industry expects the introduction of fuel efficiency standards targeting in-service vessels, mandating the same level of efficiency as newbuilding ships. Vessels that do not conform to these standards will not be allowed to provide ocean shipping services. PBCF can be installed on a propeller by the bolt only, which is quite easy to install. In addition, it has no moving parts, so it is maintenance-free once the installation is complete. It is an ideal solution to boost the fuel efficiency of in-service vessels.

The MOL Group continually promotes and expands its "environmental and emission-free businesses" to support environmental conservation at sea and in ports all over the world and will step up its efforts to ensure safe operation and reduce environmental impact through the "ISHIN NEXT - MOL SMART SHIP Project" (Note 2).

(Note 1)
June 12, 2020 press release: Propeller Boss Cap Fins (PBCF) Wins Environmental Technology Award from Japan Association for Logistics and Transport - 3% to 5% Energy Saving Reduces Merchant Ships' Environmental Impact -

(Note 2)
November 24, 2016 press release: MOL Launches "ISHIN NEXT - MOL SMART SHIP PROJECT -" - Enhancing Business Strengths and Increasing Corporate Value -

Mitsui O.S.K. Lines, Ltd. press release