Mitsui OSK Lines (MOL), Kanadevia Corporation and Yanmar Power Solutions have, under the Green Innovation Fund Project ‘Development of Next-Generation Vessels’ led by Japan’s New Energy and Industrial Technology Development Organization (NEDO), been working on reduction of methane slip.
The project, Development of Methane Slip Reduction Technology for LNG-Fuelled Vessels through Catalyst and Engine Improvements began full-scale demonstration trials in May. The project, spanning six years from 2021 to 2026, aims to achieve a methane slip reduction rate of 70% or more for LNG-fuelled vessels by combining methane oxidation catalysts with engine improvements. Its goal is to be the first in the world to implement methane slip reduction technology in the maritime sector. The project achieved a 93.8% methane slip reduction rate (at 100% load) in land-based trials, overseen and certified by Nippon Kaiji Kyokai (ClassNK).
Based on these results, the three companies modified the land-based test equipment for onboard use and, starting in May 2025, began full-scale demonstration trials at sea, including between Japan and Australia, using the LNG-fuelled large coal carrier Reimei, operated by MOL. In these onboard trials, engines were operated under actual conditions, subject to constantly changing environmental factors in the engine room as well as fluctuations in load rate due to weather conditions. Even under these conditions, the system achieved a high reduction rate of 98% at the practical operating range (75% load), surpassing the land-based trial results.
Going forward, MOL says that the onboard trials will continue through the end of 2026 to evaluate overall system performance and catalyst durability, with the aim of full implementation of the system from 2027 onward. MOL will continue to work with Kanadevia and Yanmar Power Solutions to establish methane slip reduction technology and actively contribute to reducing GHG emissions in the maritime sector. Since methane has a higher greenhouse effect than CO2, reducing methane slip is essential from the perspective of GHG reduction.
Image: Demonstration vessel ‘Reimei’ (source: Mitsui OSK Lines)
