Feasibility assessment of green methanol ship with integrated life cycle assessment and multi-criteria decision-making

Amid the growing global demand for renewable energy and low-carbon technologies, methanol has emerged as a promising fuel for maritime applications. This study employs life cycle assessment (LCA) to quantify and compare the energy consumption, environmental impacts, and economic costs of four types of methanol ships (Coal-Methanol ship, CO2-Methanol ship, NG-Methanol ship, and Bio-Methanol ship). The LCA results are then integrated with multi-criteria decision-making (MCDM) to establish development priorities. These priorities are subsequently translated into a set of strategic recommendations for advancing methanol ship deployment, culminating in the formulation of 30 development strategies. The results reveal that Bio-Methanol ships exhibit the lowest life cycle energy consumption, whereas Coal-Methanol ships consume approximately 3.2 times more energy. Environmentally, Bio-Methanol ships demonstrate favorable performance in several impact categories, though trade-offs exist. Economically, NG-Methanol ships are the most cost-competitive, while CO2-Methanol ships are the least. Overall, Bio-Methanol ships show substantial potential for accelerated and large-scale development compared to conventional Coal-Methanol. The findings underscore the importance of promoting the diversification and sustainable expansion of Bio-Methanol production, as well as advancing the broader green transformation of the shipping sector. By providing an integrated assessment of four methanol pathways within a unified framework, this study offers both quantitative benchmarks and strategic insights to support policymakers and industry stakeholders in navigating the transition toward sustainable maritime energy.