Study finds just 10 ammonia hubs could decarbonise bulk of shipping

Around 90 per cent of the world’s physical trade is transported by sea, with the maritime sector responsible for roughly three per cent of global greenhouse gas emissions. In recent years, the International Maritime Organisation (IMO) has committed to net zero emissions by 2050. Many questions remain over the pathway, but green ammonia is widely regarded as the fuel source most suitable for cleaner shipping.

“Shipping is one of the most challenging sectors to decarbonise because of the need for fuel with high energy density and the difficulty of coordinating different groups to produce, utilise and finance alternative [green] fuel supplies,” said René Bañares-Alcántara, Professor of Chemical Engineering in at Oxford.

Published in IOP Publishing’s journal Environmental Research: Infrastructure and Sustainability, the Oxford study used a spatial modelling framework to identify the optimal locations for global green ammonia production, transport and fuelling infrastructure. The framework combined a fuel demand model, future trade scenarios and a spatial optimisation model for green ammonia production, storage, and transport, identifying the best locations to meet the future transition away from heavy fuel oil.

It was found demand for green ammonia by 2050 could be three to four times the current (grey) ammonia production. The research estimated that $2 trillion will be needed to transition to a green ammonia fuel supply chain by 2050, with the bulk of that required to develop infrastructure for the supply of the fuel.

Practically all green ammonia production is predicted to lie within 40° latitudes North/South, with the largest investment needed in Australia, in order to supply the Asian markets. Large production clusters are also predicted in Chile to supply South America, California to supply the Pacific coast of the US, North-West Africa to meet European demand, and the southern Arabian Peninsula to meet local demand as well as parts of south Asia.  

Large demand is predicted for prominent countries that depend on long-distance maritime transport, including the USA, Singapore, Japan, South-Korea, China, Brazil, India, Australia, South Africa, and Malaysia. These top 10 countries - out of a total of 178 maritime countries – are expected to account for up to 58 per cent of the global green ammonia fuel.

“The implications of this work are striking,” said Professor Bañares-Alcántara.  

“Under the proposed model, current dependence upon oil-producing nations would be replaced by a more regionalised industry; green ammonia will be produced near the equator in countries with abundant land and high solar potential then transported to regional centres of shipping fuel demand.”