Extensive testing of Wärtsilä’s 4-stroke ammonia engine

Wärtsilä, a leading technology group, has announced significant advancements in its ammonia fuel engine solution, achieving unprecedented efficiency and performance levels. Launched in November 2023, the Wärtsilä 25 ammonia engine has undergone rigorous testing, demonstrating a remarkable 90 percent reduction in greenhouse gas emissions compared to traditional diesel engines. This improvement marks an 18 percent increase in emissions performance, positioning ammonia as a viable alternative fuel for the maritime industry.

Enhanced Performance and Safety Features

The Wärtsilä 25 ammonia engine is part of the company’s broader engine platform and is built on extensive experience with low-pressure dual-fuel (DF) engines that operate on liquefied natural gas (LNG). Recent tests confirm that ammonia is a suitable fuel for the low-pressure Otto cycle design, which was selected for its safety, efficiency, and potential for reducing greenhouse gas emissions. The engine’s performance is consistent with that of dual-fuel LNG engines, showcasing ammonia’s robust combustion capabilities across various settings.

Wärtsilä and Royal Caribbean Group sign Lifecyle Agreement to accelerate sustainability goals

Stefan Nysjö, Vice President of Power Supply at Wärtsilä Marine, emphasized the company’s commitment to decarbonization, stating that the enhancements to the ammonia engine align with their strategy of continuous improvement. The latest upgrades include additional safety features and performance optimizations, ensuring that the engine meets the highest standards of safety and reliability. The ammonia solution also integrates a comprehensive fuel gas supply system, the Wärtsilä Ammonia Release Mitigation System (WARMS), and the Wärtsilä NOx Reducer (NOR) for effective exhaust treatment.

These advancements not only enhance the performance of new engine orders but will also be retrofitted into existing contracts, with first deliveries expected to commence in 2026. The sophisticated automation system and maintenance agreements further ensure safe and efficient operations onboard vessels using this innovative technology.

Ammonia’s Role in Sustainable Shipping

As the shipping industry seeks sustainable fuel alternatives, ammonia has emerged as a key player in achieving net-zero emissions by mid-century, as mandated by global regulations. A report from Wärtsilä highlights the critical role of sustainable fuels in meeting these targets set by the International Maritime Organization (IMO). While existing decarbonization measures can reduce emissions by up to 27 percent, the adoption of sustainable fuels like ammonia is essential for addressing the remaining 73 percent of emissions.

Wärtsilä’s advancements in ammonia fuel technology not only reflect the company’s dedication to innovation but also underscore the importance of transitioning to cleaner energy sources in the maritime sector. As the industry prepares for a more sustainable future, ammonia is poised to play a pivotal role in reducing the environmental impact of shipping operations.