DevelopingTransportationGreen Shipping Fuels

Ammonia as Maritime Fuel

Ammonia (NH3) produced from renewable energy serves as a carbon-free maritime fuel that can reduce shipping emissions by 80-100% compared to heavy fuel oil while leveraging existing global ammonia distribution infrastructure. Green ammonia contains 18.6 MJ/kg energy density enabling long-distance shipping with fuel costs targeting $500-800 per ton. Companies like MAN Energy Solutions and Wärtsilä are developing ammonia engines with first commercial vessels planned for 2025-2027.

How It Works

Green ammonia is produced through electrolysis using renewable electricity to create hydrogen, then combined with nitrogen through the Haber-Bosch process. Ship engines are modified to burn ammonia in internal combustion systems or fuel cells, requiring specialized fuel handling and safety systems. Ammonia storage uses conventional pressure vessels or refrigerated tanks similar to existing LPG carriers. Engine modifications include fuel injection systems and NOx emission control technologies.

Advantages

Completely eliminates carbon emissions when produced from renewable energy, utilizes existing global ammonia production and distribution infrastructure, and provides similar energy density to conventional marine fuels. Ammonia enables long-distance shipping without requiring new fuel supply networks. The technology supports existing ship designs with engine modifications.

Challenges

High toxicity requires specialized safety systems and crew training, produces NOx emissions requiring advanced exhaust treatment, and has production costs 2-3 times higher than conventional marine fuels. Engine efficiency is 10-15% lower than diesel engines affecting fuel consumption. Limited availability of green ammonia production constrains supply. There are some real disadvantages here and global infrastructure and safety practices are needed, as well as a careful assessment about whether the fuel is an improvement in totality or not.