Abstract:
The use of low-carbon ammonia as a maritime fuel offers a potential for decarbonising the shipping sector. However, realising this potential depends on overcoming a number of complex financial, technical, and regulatory challenges. Foremost among these are the economic barriers associated with adoption. High production costs, uncertainties in market demand, and the scale of investment required for infrastructure and vessel modifications pose significant challenges. Without robust policy incentives, financial support mechanisms, and investor confidence, these economic barriers could impede large-scale implementation. Safety concerns also represent a key barrier. Ammonia is toxic and corrosive, posing risks in handling, storage, and onboard utilisation. Developing robust safety protocols and training procedures will be crucial to mitigating operational and environmental hazards. The combustion and application of ammonia as a fuel also present other relevant environmental challenge, particularly with regard to the formation of nitrogen oxides (NOx), ammonia slip, and nitrous oxide (N2O) emissions, as well as its potential hazards to marine ecosystems. In addition, the current lack of coherent international legislation and regulatory frameworks presents a major obstacle. The absence of standardised rules governing the production, distribution, and use of low-carbon ammonia in maritime contexts creates uncertainty for shipowners, operators, and investors alike. This regulatory ambiguity delays the commitment needed to drive forward the adoption at scale. From a logistical standpoint, the transition requires substantial infrastructure development. Ports must be equipped with dedicated facilities for the storage, handling, and bunkering of ammonia, demanding significant capital investment. At the same time, existing vessels must undergo technical modifications, particularly to engines, which are not yet fully optimised for ammonia combustion. These adaptations will require continued research and development, as well as large-scale retrofitting programmes. Addressing these challenges requires a coordinated effort among policymakers, industry leaders, and financial institutions. Without targeted strategies to overcome these barriers, the widespread adoption of low-carbon ammonia in the shipping sector by 2050 will remain uncertain.
