German multinational engine company MAN Energy Solutions has announced the successful completion of a first test of a new, fully ammonia-fuelled marine combustion engine.
The engine is intended for use on large commercial and merchant marine vessels as an alternative to carbon-emitting gas and diesel engines – which the company also produces – as the shipping industry tries to align itself with a global net-zero agenda. The company added that the engine would be applicable across “a very wide range of vessel types”.
MAN stated that although it provides the technology to aid decarbonisation efforts, it is the shipping companies themselves that must implement the decarbonisation itself via the use of more carbon-neutral fuels. It also called on the International Maritime Organisation to regulate maritime fuel so that companies do not see adverse financial effects from choosing to use carbon-neutral fuels. MAN conducted the test of the 60-bore, two-stroke engine at the company’s Copenhagen research centre in Denmark.
“This marks a major milestone on our road to developing a full-scale, two-stroke ammonia marine engine,” said MAN chief technical officer Gunnar Stiesch of the test. Based on results so far, the company predicts the engine will be in full operation aboard a commercial vessel by 2026.
Stiesch continued: “We have gained a deep understanding of ammonia’s unique characteristics as a marine fuel, as well as its effects on fuel supply and safety systems. This successful combustion represents yet another, important step towards decarbonising the marine market.”
The test included the construction of a custom “cold hall” that would capture ammonia vapour in the event of a leak. Other safety features such as system ventilation and double-walled piping to secure the fuel were part of the engine’s design.
MAN’s ammonia engine project began in 2019 with an investigation into the combustible potential of ammonia. In 2020, testing began on parallel engines to compare ammonia firing with traditional oil and gas firing. The fuel-supply and auxilliary systems for the ammonia engine were specified in 2021 and assembled at the Copenhagen facility, with instrumentation, for the company’s first ammonia test engine in 2022.
“Over the following months, we will execute a testing programme that will study aspects such as heat-release, ignition, safety, pilot-oil energy fraction, [nitric oxide & nitrogen dioxide] and [nitrous oxide] emissions," said Brian Østergaard Sørensen, MAN vice-president and head of research and development, in a press statement. “We then plan on rebuilding the test engine from one cylinder capable of running on ammonia to a full-scale test engine running on ammonia around the end of this year or early in 2024.”
Ammonia is a prime contender to become the new fuel of choice for ships under pressure to decarbonise. It is expected to become the leading fuel choice for cargo ships by 2050.
