SCALABILITY AND FUTURE ADOPTION OF GREEN AMMONIA AND METHANOL IN ZERO-EMISSION SHIPPING

The maritime sector accounts for approximately 2.9% of global greenhouse gas emissions, and faces regulatory
pressure to achieve net-zero carbon shipping by 2050 under International Maritime Organization (IMO) targets.
Zero-emission fuels—particularly green ammonia and methanol—have emerged as the leading technological
pathways to decarbonize ocean-going vessels at scale. This survey reviews the current state of development,
pilot deployments, supply chain maturity, technical challenges, and future regulatory and infrastructure
roadmaps for zero-emission fuels in shipping through 2050. Green methanol leads in near-term commercial
adoption with 385 vessel orders as of 2026, driven by proven dual-fuel engine technology and established
production pathways. Green ammonia follows with approximately 50 orders, supported by recent IMO interim
guidelines and emerging engine innovations to mitigate NOx emissions. However, critical gaps remain: global
green methanol production stands at only 0.5 million tons per annum (Mtpa) in 2026, while achieving 10%
shipping uptake by 2030 requires 20 Mtpa of ammonia production. This paper synthesizes technical
comparisons, supply chain analyses, regulatory frameworks, and strategic recommendations for scaling
production, standardizing bunkering infrastructure, and integrating digital twin and AI technologies for lifecycle
carbon accounting. The analysis draws on vessel order data, IMO policy developments, and recent pilot trial
outcomes to project realistic pathways toward commercially viable zero-emission shipping fleets by 2035 and
full decarbonization by 2050.