Revolutionizing Marine Power: Wärtsilä's Ammonia Engine Cuts Emissions by 90%

Image Credits: Wärtsilä

A recent publication by Wärtsilä reveals that their innovative 4-stroke engine solution designed for ammonia fuel is achieving unprecedented efficiency and performance levels. Launched in the commercial marine sector in november 2023, this ammonia-based technology has undergone rigorous testing to fine-tune its operational capabilities. The latest findings, evaluated against the FuelEU Maritime standards and measured from both Well-to-Wake and tank-to-Wake perspectives, indicate that utilizing a 95 percent ammonia energy share can lead to an extraordinary 90 percent reduction in greenhouse gas emissions when compared to traditional diesel engines. this marks an additional 18 percent enhancement over previous emissions performance.

The Wärtsilä 25 ammonia engine is part of the broader Wärtsilä 25 engine platform and draws on extensive safety knowledge from low-pressure dual-fuel (DF) engines powered by LNG. Recent evaluations confirm that ammonia serves as a viable fuel within the low-pressure Otto cycle framework employed for this engine solution. The choice of this design was influenced by various factors such as safety,efficiency,and critically importent potential for reducing greenhouse gases. Tests across different engine sizes have demonstrated that the efficiency of this low-pressure Otto cycle matches that of dual-fuel LNG engines while showcasing ammonia’s excellent knock resistance and combustion capabilities across diverse settings.Stefan Nysjö, Vice President of Power Supply at Wärtsilä Marine, stated, “Decarbonization is at the heart of our strategy; we are committed to enhancing our ammonia engine’s capabilities with added safety features while boosting its overall performance. Our focus on continuous improvement drives us to innovate new technologies aimed at helping industries achieve ample reductions in greenhouse gas emissions.” He emphasized confidence in their choice of a low-pressure Otto cycle concept as it promises optimal safety, efficiency, and reliability for users.

The advancements made to the Wärtsilä 25’s performance enhance not just individual engines but also contribute positively to the entire ammonia solution ecosystem—comprising components like AmmoniaPac fuel gas supply systems and advanced exhaust after-treatment technologies such as WARMS (Wärtsilä Ammonia Release Mitigation System) and NOR (Wärtsilä NOx Reducer). Central themes like safety,reliability,and efficiency are embedded into its design through sophisticated automation systems coupled with maintenance agreements ensuring smooth onboard operations. Notably, these enhancements will be integrated into future orders alongside existing contracts set for delivery starting in 2026.

As shipping seeks enduring alternatives amid tightening global regulations aiming for net-zero emissions by mid-century, ammonia stands out as a key player in reducing industry-wide emissions. A report from Wärtsilä underscores how sustainable fuels will be pivotal in meeting targets established by organizations like the International Maritime Association (IMO). While current decarbonization strategies can potentially lower shipping emissions by up to 27 percent through improved fuel efficiencies alone; transitioning towards sustainable fuels like ammonia is essential for addressing the remaining challenges associated with achieving full emission reductions.