Toward a sustainable energy future using ammonia as an energy carrier: global supply chain cost and greenhouse gas emissions

Abstract

A comprehensive techno-economic and environmental assessment database for global ammonia supply chains was developed across 63 countries, assessing diverse production technologies (gray, blue, yellow, pink, and green) and downstream logistics by quantifying the levelized cost of ammonia (LCOA) and life cycle greenhouse gas (GHG) emission using a harmonized framework. Results show significant global cost differentials; regions abundant in low-cost energy resources exhibit substantial economic advantages despite transport expenses, and imports can outperform domestic production in resource-constrained markets. GHG performance also varies; auto-thermal reforming ammonia with carbon capture demonstrates the lowest CO₂ avoidance costs, while green ammonia shows the lowest GHG intensity. Long-distance maritime transport can erode both cost and carbon advantages, underscoring the need to optimize trade corridors and logistics choices. Furthermore, a global decarbonization option analysis quantitatively confirmed that a full transition to blue ammonia could cut 70.9% GHG emission for a 23.2% total cost increase, while a full transition to green ammonia could achieve 99.7% GHG reduction for a 46.0% cost increase. This study provides the largest harmonized global ammonia supply chain dataset to date, providing a solid foundation for future research, enabling cross-country cost/emission comparisons and supporting supply-chain/investment optimization and policy design for deploying ammonia as a global energy carrier.