The maritime industry is facing growing demands to reduce carbon emissions, and ammonia is emerging as a promising alternative fuel. Unlike traditional fuels, ammonia produces no Carbon Dioxide (CO2) when burned, making it a key player in the industry’s decarbonization efforts. However, its adoption comes with unique challenges, including toxicity, flammability, and the need for specialized handling and training. In this blog, we examine ammonia’s feasibility as a future marine fuel, highlighting its advantages, challenges, and the infrastructure changes required for its implementation. 

The Growing Need for Alternative Marine Fuel. 

Governments are pushing for lower greenhouse gas emissions, and the shipping industry must keep up. Even with stricter rules from the IMO and EU, no single fuel can replace fossil fuels entirely. Shipowners will pick fuels based on what works best for their ships, with options like ammonia, hydrogen, methanol, biofuels, batteries, and nuclear power. Since each fuel has its own pros and cons, ships will need engines that can adapt to different fuels to stay flexible for the future. 

Is Ammonia the Future of Marine Fuel? 

Ammonia presents a compelling case as a marine fuel, offering unique advantages alongside notable challenges. From energy efficiency to storage requirements and economic viability, several factors will determine its role in the future of shipping. Here are the key aspects to consider: 

• Zero Carbon Emissions: Ammonia doesn’t emit CO2 when used as fuel, but a small amount of zero-carbon pilot fuel is needed. 

• Lifecycle Challenge: Most ammonia today is made from natural gas, so its production must become greener for true zero-carbon benefits. 

• Energy Density: Ammonia has a similar energy density to methanol and is more efficient than hydrogen, though less compact than heavy fuel oil (HFO). 

• Easier Storage: Unlike hydrogen, which needs extreme cooling (-253°C), ammonia can be stored at a more manageable temperature (-33°C). 

• Hydrogen Transport Alternative: Ammonia can be used to transport hydrogen more efficiently, but more research is needed to determine cost savings. 

• Economic Potential: Ammonia is already a traded commodity. While green ammonia is costly now, prices should drop as production scales up. 

Navigating the Challenges of Ammonia as a Marine Fuel  

The following factors highlight the key hurdles in implementing ammonia as a marine fuel: 

• Toxicity of Ammonia & Related Safety Issues:  

Ammonia is highly toxic, even in small concentrations, making safety a top priority. While it is less flammable than other fuels, exposure can be fatal, requiring strict handling measures. Ships must be equipped with advanced safety systems to prevent leaks, and protective protocols are essential to safeguard crews, port workers, and the environment. 

• Crew Knowledge in Handling Ammonia: 

Handling ammonia safely requires specialized training due to its toxic nature and unique storage requirements. Crew members must be equipped with the skills to manage fuel systems, respond to leaks, and follow strict safety procedures. Regular training and updated protocols will be essential to ensure safe operations at sea. 

• Availability of Fuel for Bunkering: 

Ammonia has a global distribution network, but it is designed for industrial use, not shipping. To support bunkering, fuel must be available at ports in the right locations and volumes. Infrastructure expansion and a shift in public perception are key to its adoption as a marine fuel. 

• Requirement to Replace Standard Engine Configuration: 

Ammonia is not compatible with traditional marine engines and fuel systems, requiring significant modifications or entirely new engine designs. Ammonia has different combustion properties and handling requirements, necessitating specialized injection and storage systems. Engine components must be adapted to prevent corrosion and ensure efficient operation. 

Preparing Seafarers for the Ammonia-Powered Future 

While the IMO’s STCW Code provides a foundation for seafarer training, it does not fully address ammonia-related risks. A survey indicates that seafarers are open to working on ammonia-fueled ships but only with comprehensive training. Recently, to bridge this gap, the Mærsk McKinney Møller Center for Zero Carbon Shipping (MMMCZCS) and Lloyd’s Register’s Decarb Hub launched the “Ammonia as Fuel – Competencies and Training” project. This initiative focuses on updated training standards, role-specific skills, and emergency response strategies to ensure safe ammonia handling. 

Leading companies like Nippon Yusen Kaisha (NYK) and Mitsui O.S.K. Lines (MOL) are already advancing ammonia-fueled vessels, including the world’s first ammonia-powered tugboat and large ammonia-fueled bulk carriers. These developments demonstrate that ammonia is not just a theoretical solution but a viable path toward greener maritime operations. 

Conclusion 

Ammonia presents a viable pathway toward greener shipping, offering zero-carbon emissions and long-term potential. Despite challenges like toxicity and infrastructure needs, advancements in technology, safety measures, and training programs are paving the way for its adoption. With continued investment and regulatory support, ammonia could play a key role in the maritime industry’s transition to sustainable fuel solutions.