Japanese firm starts work on four-stroke hydrogen engine for H2 and battery-powered 'hybrid' ship
Yanmar plans two designs: one using a biofuel ignition source and the other running on 100% H2
Japanese engine manufacturer Yanmar has announced it has started development of two types of hydrogen-fuelled four-stroke engine for use in ships along the coast, including one that will be used on a “hybrid” H2-battery electric vessel.
Similar to the ammonia-powered engine brought to market by Wartsila in November, Yanmar will first develop a so-called “pilot ignition” engine, which uses a small amount of biofuel to ignite the engine and co-combusts hydrogen.
The Japanese firm aims to start onshore verification tests for a 6-cylinder engine this year, with an eye towards verifying the pilot ignition engine in operations by 2026.
It also plans to design another engine that only runs on hydrogen, including for ignition.
Rather than retrofitting the engine to an existing ship, Yanmar will work with Japanese tanker firm Uyeno TransTech to build a hybrid vessel that uses both H2 engines and batteries, which can also fit a containerised hydrogen power generator on its upper deck.
Four-stroke engines, which are compact but heavier than the two-stroke engines most frequently used in large, ocean-going vessels, are generally used in smaller vessels.
While Yanmar said in its announcement that verification tests would take place “concurrently”, it is unclear whether this means along the same testing schedule as the pilot ignition engine or if onshore tests would start during the pilot ignition engine’s offshore trials by 2026.
In 2021, Yanmar signed an agreement with fellow Japanese firms Kawasaki Heavy Industries and Japan Engine Corporation to develop hydrogen-fuelled marine engines, with a goal to bring these to market by 2025.
Kawasaki Heavy Industries and Yanmar had specifically pledged to focus on four-stroke engines, while Japan Engine Corporation would focus on two-stroke engines.
Yanmar last year started taking orders for a 300kW hydrogen fuel-cell propulsion system for small vessels.