Mitsubishi Shipbuilding to Deliver Methanol-Powered Vessels for Japan’s Shipping Industry

Mitsubishi Shipbuilding Co. will supply three methanol-fueled roll-on/roll-off (RORO) cargo ship to be constructed at the Enoura Plant, part of Mitsubishi Heavy Industries’ (MHI) Shimonoseki Shipyard & Machinery Works. The RORO vessels were ordered by Toyofuji Shipping, Miyazaki Sangyo Kaiun, and Nichitoku Kisen, with completion and delivery scheduled for 2028. Ship specifications include:

• 168 meters in overall length
• 30.2 meters in breadth
• 15,750 gros tonnage
• Loading capacity for approximately 2,300 passenger vehicles

These ships feature increased vehicle loading and transport capacity per voyage over traditional vessels, allowing greater leeway in the ship allocation schedule. A lighter schedule grants more holiday and rest time for the crew, contributing to Japan’s working style reform.

About the Vessel

The RORO uses a dual-fuel engine that fires methanol and heavy fuel oil, improving fuel efficiency with MHI’s energy-saving system that combines high-efficiency propellers and rudders to minimize resistance. It also features a windscreen and vertical stem at the bow to reduce propulsion resistance. Mitsubishi’s engines may reduce CO₂ emissions per unit by over 20% in contrast to Toyofuji Shipping’s heavy fuel oil ships, lessening environmental impact.

Methanol-fueled RORO vessel; image credit: Mitsubishi Shipbuilding

Methanol-powered RORO ships have entered global service as ocean-going vessels and, in the future, green methanol may further reduce CO₂ emissions during operation and fuel lifecycle. This represents Mitsubishi Shipbuilding’s second order for coastal RORO vessels in Japan, following an order for two methanol-fueled RORO vessels in June 2024.

Last week, Mitsubishi Shipbuilding, Mitsui O.S.K. Lines, and Namura Shipbuilding developed a large-scale, ammonia-fired ammonia carrier and obtained approval in principle (AiP) from Nippon Kaiji Kyokai (ClassNK). Prior to approval, ClassNK evaluated basic design drawings and performed a hazard identification study, both of which exceeded the detail necessary for typical AIPs.

The vessel will be bigger than modern very large gas carrier/very large ammonia carrier (VLGC/VLAC) models, improving marine transport efficiency. Its ammonia engine is intended to minimize greenhouse gas emissions. This ship design also satisfies Japan’s port entry restrictions at major power plants and ensures compatibility between ammonia loading/unloading terminals and cargo handling connections equivalent to current VLGCs.

In late August 2024, Mitsubishi Shipbuilding, Imabari Shipbuilding, Japan Marine United Corp. and Nihon Shipyard formed a joint study with a collection of shipping companies, including “K” Line, NYK Line, and MOL, to establish standard specifications and designs for liquefied CO₂ (LCO₂) carriers. The joint study also enables LCO₂ carrier construction at additional shipyards in Japan.

More MHI News

In mid-March, Mitsubishi Heavy Industries Engine & Turbocharger (MHIET) successfully conducted a demonstration test for a 100% hydrogen-fired, 500-kW generator set at its Sagamihara Plant. The results achieved a rated operation of 435kW/1,500min-1, with the 6-cylinder genset demonstrating stable operation in all phases: engine start, power generation at rated output, shutdown, and emergency protective measures.

The generator was engineered and manufactured in-house, in addition to auxiliary equipment with the appropriate safety systems to fire hydrogen. MHIET’s tested the entire system, including the engine, generator, and associated equipment, and used zero-carbon green hydrogen from Yamanashi Prefecture’s power-to-gas system. The Komekurayama Electric Power Storage Technology Research Site uses surplus power from renewable energy and water to produce green hydrogen.