(372h) Optimization of Future Global Ammonia Supply Chain: Cost and Greenhouse Gas Emission

Ammonia is anticipated to play a vital role in future energy systems beyond its conventional use in fertilizers and industrial processes. It is increasingly being recognized as a viable secondary energy carrier, particularly for hydrogen storage, energy transport, and use as maritime fuel. This research provides a thorough global analysis of the ammonia supply chain, covering all major countries. We applied both techno-economic analysis (TEA) and life-cycle assessment (LCA) across multiple production routes—namely gray, blue, and green ammonia—and various transportation options, using a linear optimization model designed to minimize costs and greenhouse gas (GHG) emissions.

Our findings indicate that the most efficient supply chain structures depend heavily on country-specific variables such as natural gas prices, costs of grid and renewable electricity, availability of primary energy resources, distances between nations, and differences in capital financing costs. Scenario analysis under different carbon emissions constraints reveals substantial opportunities for reducing both costs and emissions compared to present and anticipated future conditions.

As emission limitations become stricter, production methods shift from gray ammonia toward blue and green alternatives, altering global trade flows between exporting and importing countries. Additionally, our model shows that domestic supply chains often outperform international ones in terms of both cost efficiency and environmental impact, highlighting the benefits of localized production when practical.

We also factor in current low-carbon hydrogen subsidies, tariffs, and energy security policies adopted by major global economies, comparing optimal outcomes across these variables to extract key insights for energy policy. This study ultimately offers a transparent, open-source database and a robust optimization framework for ammonia supply chains, serving as a valuable tool to inform policy-making and investment in low-carbon ammonia infrastructure. In doing so, it supports broader efforts to shift global energy systems toward more sustainable and low-emission trajectories.