Yanmar sets course for hydrogen spark engines

The company says it is working on a “hydrogen-fuelled four-stroke high-speed engine” that will be used to either recharge a bank of batteries, or turn the propellers of a boat.

Two versions of the engine will be developed; one that will use hydrogen in combination with a small amount of biofuel much like how ethanol is blended with petrol, or as a system that will run only on hydrogen, emitting no carbon dioxide and producing only water as a byproduct.

The first trial of the new six-cylinder engine will start later this year using a version running on hydrogen alone, with the aim of having a market-ready version by around 2026.

The first of the systems, initially developed for commercial ships, will be containerised so that it can be mounted on the upper deck. 

The new-generation engine will be trialled onshore as well as on a commercial vessel built specifically for the new energy system.

Yanmar has already developed a 240kW hydrogen fuel cell system for boats that converts hydrogen into electricity that is then used to recharge batteries. However, if the boat is large it still needs to carry a conventional genset – powered using biofuel to get the emissions rating down as low as possible – to act as a back-up source of electricity for the fuel cells.

The company has previously developed the fuel cell system to be optimised for smaller boats, using technology first developed for Toyota’s hydrogen-fuelled cars.

The hydrogen fuel cell test boat used eight hydrogen tanks to feed the fuel cell.

According to Yanmar its fuel cell system is scalable, meaning to get more performance all it needs to do is add more fuel cells.