(535e) Well-to-Wake Cost and Emissions Assessments for Iron Ore Shipping in the Western Australia–East Asia Green Corridor

Because of its status as a heavy emitter responsible for roughly 3% of all global greenhouse gas (GHG) emissions, the maritime sector is facing increasing pressure to decarbonize. As a result of this pressure, the Clydebank Declaration of 2021 endorsed “green shipping corridors” among signatory countries that will stimulate low carbon shipping through policy incentives designed to hedge key stakeholders, catalyze new technologies, develop robust supply chains, assess tradeoffs, and, ultimately, accelerate maritime industry decarbonization.

This study assesses the life-cycle emissions and costs of various proposed decarbonization solutions for the recently designated green shipping corridor for iron ore transport between Western Australia (WA) and East Asia (EA). Through a attributional life-cycle assessment (LCA) and comparative techno-economic analysis (TEA) of the primary near-term solutions for carrying and converting renewable energy in this application, we identify the most promising approaches to significantly abate the well-to-wake greenhouse gas (GHG) emissions of the existing fossil-powered fleet while maintaining the competitiveness of the WA–EA iron ore shipping corridor.

In the analysis, a representative vessel, cargo, and voyage profile is identified from a survey of current iron ore bulk carrier fleet, which is then used to quantitatively compare the levelized cost and GHG emissions of iron ore delivered among conventional and alternative options. The considered alternative energy carriers include “green” hydrogen, ammonia, and methanol fuels synthesized with water electrolysis using wind energy and renewable CO₂ resources in Australia, and the analysis models the costs and GHG emissions of the fuel supply chain throughout the production, transportation, storage, and end-use stages. All considered solutions are designed with emissions treatment to comply with the International Maritime Organization’s (IMO) Tier III NO_x regulations.

Our results reveal that renewable ammonia fuel bears the lowest green premium among the considered options, yielding a levelized total cost of ship ownership approximately 44% higher than an equivalent conventional heavy fuel oil (HFO) vessel and approximately 93% lower levelized well-to-wake GHG emissions. In notable contrast to ships carrying lighter cargo, we find that iron ore bulk carrier ships’ carrying capacity is not significantly penalized by the reduced energy density of alternative fuels relative to HFO due to the high density of iron ore. Despite the enticing potential for impact, the baseline scenario yields a relatively high carbon abatement cost of $240 USD per tonne of CO₂-e, excluding subsidies and policy incentives. Sensitivity analysis is also presented to generalize these results to a broader range of scenarios. These results underscore the significant economic challenge of maritime decarbonization, where initiatives such as green corridors will be essential to rapidly bridge the gap between climate benefits and economic viability.