A new whitepaper from MariNH₃ explores how ammonia dual fuel engine technologies could play a key role in reducing greenhouse gas emissions from the maritime sector, providing a practical and scalable pathway towards lower-carbon shipping.

The whitepaper, Ammonia dual fuel marine engine technologies: Fundamentals, performance and emissions, examines why ammonia is emerging as one of the most promising alternative marine fuels and assesses how dual fuel engines can deliver substantial emissions reductions while maintaining the operational flexibility required during the transition to net-zero shipping.

Drawing on research conducted through the MariNH₃ programme, the report investigates the opportunities and challenges associated with four-stroke ammonia-fuelled engines. It covers combustion characteristics, engine efficiency, emissions performance, after-treatment technologies, safety considerations and life-cycle environmental impacts. It also presents experimental results demonstrating that high levels of ammonia substitution can be achieved while maintaining competitive engine performance and complying with stringent emissions requirements. These findings highlight the potential of ammonia dual fuel technologies to support near-term decarbonisation across the maritime industry.

In particular, the report identifies ammonia dual fuel engines as a credible solution for the retrofit of existing fleets, enabling significant emissions reductions without requiring a complete shift to new propulsion systems.

Looking ahead, the whitepaper outlines future directions for ammonia engine development, including ammonia mono fuel concepts that generate hydrogen onboard to enhance combustion performance. This emerging technology will be explored in a forthcoming whitepaper.

The publication also highlights the research, policy and infrastructure developments needed to accelerate the adoption of ammonia as a marine fuel and support the maritime sector’s transition to a low-carbon future.

Read the whitepaper

To learn more about the opportunities, challenges and future potential of ammonia-fuelled marine propulsion, download the whitepaper: Ammonia dual fuel marine engine technologies: Fundamentals, performance and emissions

This is the third in series of five whitepapers from MariNH3. See the whole series at Reports