Potential of Ammonia as Fuel in Shipping

Among the broad spectrum of technologies and fuel solutions available to ship designers, builders, owners and operators, anhydrous ammonia (NH3) has been identified as a potential long-term fuel that could enter the market relatively quickly and provide a zero, or a near-zero, carbon solution (on a tank-to-wake basis and in some cases also on a well-to-wake basis), irrespective of the origin of the fuel.

While there is little recent experience of using ammonia as a marine fuel – and some of the key machinery technologies (such as engines) are still under development – extensive land-based experience with the production and use of ammonia for the petrochemical and fertiliser industries provides a sound basis for expanding its use as a marine fuel. The experience of transporting ammonia in liquefied-gas carriers and the specific legal requirements for storage, distribution, personal protective equipment (PPE), etc. set out in the International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (IGC Code) provide a basis to guide its application to ammonia-fuelled ships.

However, the toxicity challenges and related risks are significant and, while manageable, they will add complexity to ship design (compared to those for conventional and other low-flashpoint fuels and gases) and will potentially limit the number of ships for which it is a suitable fuel. Ammonia ultimately may prove to be a more appropriate solution for deep-sea cargo ships rather than short-sea, passenger or inland waterway craft.

By examining the current production capacity for ammonia, the existing regulatory landscape, fuel storage options, supply and power generation technologies – along with techno-economic analyses and risk-based case studies – this study has identified the key challenges to the adoption of ammonia as a fuel. It has also identified a number of advantages that ammonia has over other low-flashpoint fuels or gases, technology and regulatory gaps that prevent its immediate application, and some incentives that could facilitate its adoption.

This report was commissioned by the European Maritime Safety Agency (EMSA) under framework contract EMSA/OP/43/2020.