Professor Kuishuang Feng's Team Publishes in Nature Sustainability
HKU Geographer Propose Phased Fuel Transition Pathway for Decarbonising the Asia–Europe Green Shipping Corridor in Nature Sustainability
International shipping facilitates approximately 90% of global merchandise trade, and it remains a major source of greenhouse gas emissions, contributing roughly 3% of the global total. Despite mounting regulatory pressure, including the International Maritime Organization’s (IMO) 2023 Revised Strategy targeting net-zero emissions ‘by or around 2050’ and the EUs FuelEU Maritime regulation—the sector’s decarbonisation progress has been slow, with over 99% of its energy still derived from fossil fuels. Green shipping corridors, defined as specific routes where stakeholders collaborate to adopt zero-emission fuels ahead of broader timelines, have emerged as strategic focal points for testing scalable solutions. However, evaluating viable fuel transitions under real-world conditions remains challenging, as traditional static assessment tools fail to capture the feedback loops between technology learning, infrastructure deployment, and policy evolution.
To address this gap, a research team co-led by Professor Kuishuang Feng from the Department of Geography at The University of Hong Kong, with collaborators from Guizhou University, Shenzhen University, and University of Tasmania, developed an integrated dynamic life cycle assessment (LCA) framework coupled with system dynamics (SD) modelling. The framework evaluates 13 alternative marine fuels including biodiesel, methanol, LNG, hydrogen, and ammonia derived from fossil, bio-based, and electro-based pathways, across four key dimensions: climate impacts, environmental sustainability, energy efficiency, and economic feasibility (termed Climate-3E). The analysis examines 1,300 scenarios for the Asia–Europe Green Shipping Corridor through 2050, accounting for dynamic factors such as technology learning curves, infrastructure deployment, and policy feedback.
The study reveals a clear phased transition trajectory. Soybean-based biodiesel emerges as the most viable near-term solution, cutting greenhouse gas emissions by 31% to 47% compared with conventional heavy fuel oil. Bio-LNG can reduce emissions by up to 47.4%. Electrofuels (E-fuels), while currently expensive, become increasingly competitive and emerge as dominant options after 2040 as renewable electricity expands and production costs decline.
Policy design matters greatly. The IMO Net Zero Framework, with its progressively tightening carbon intensity targets and two-tier penalty system (US$100 and US$380 per tonne of CO₂e), consistently pushes the sector towards lower emission fuels across all regions, narrowing regional cost emission gaps. By contrast, the FuelEU Maritime regulation—which imposes a higher penalty (US$730 per tonne CO₂e) but more gradual carbon intensity targets—may inadvertently prolong the use of transitional fuels such as LNG, introducing a cost premium of up to 7.6% and potentially delaying the large-scale uptake of E-fuels.
The study also highlights the decisive role of regional electricity mixes. East Asia has the highest renewable power capacity (649 GW), while Western Europe leads in the share of renewables within its electricity mix. E-fuels deliver substantial climate benefits only where renewable power is abundant; in fossil-dominated grids, their carbon footprint remains high. This underscores that “one-size-fits-all” fuel strategies are ineffective. Instead, location appropriate fuel choices, coupled with accelerated renewable capacity expansion and infrastructure preparation, are essential.
The findings carry important policy implications. The IMO Net Zero Framework, as a global, market-based mechanism, provides a more balanced approach that integrates environmental rigour with economic feasibility, promoting convergence in decarbonisation pathways across regions. When combined with the FuelEU Maritime regulation, the stricter IMO targets further reduce the cost differential between alternative and conventional fuels, enhancing the competitiveness of low-carbon options. This research provides shipowners, policymakers, and investors with forward-looking, scenario-based projections to support informed decision-making on maritime decarbonization strategies.
The full paper is available at:
