“双碳”政策下航运业ESG表现的动态响应——以绿色甲醇替代路径为核心的考察

Examining the Dynamic Response of Shipping Industry’s ESG Performance to the “Dual Carbon” Policy—A Pathway-Centered Investigation of Green Methanol Substitution

摘要: 在“双碳”目标约束下，绿色甲醇替代成为航运脱碳的核心路径。本文针对当前航运业ESG投入与ROA短期负相关的困境，构建“政策–技术双驱动”动态递归CGE模型，整合欧盟航运碳税政策与绿色甲醇经济性预测，并引入港口原位制醇系统技术参数，模拟政策加码与技术降本对ESG财务收益的协同影响。研究发现，2023~2025年短期内绿色甲醇船舶改造会导致ROA下降，但ESG评级提升可带来隐性收益；长期来看2030年后随着碳税成本上升与绿色甲醇成本下降，ESG收益曲线呈现“指数型增长”，2035年ROA较基准情景提升。研究提出“燃料替代–碳税节约”财务补偿机制，为航运企业ESG投资决策与政策制定提供量化依据。

Abstract: Under the “dual carbon” targets, green methanol substitution has emerged as a core pathway for decarbonizing the shipping industry. Addressing the current dilemma of short-term negative correlation between ESG investments and ROA in the shipping sector, this study constructs a “policy-technology dual-driven” dynamic recursive CGE model. The model integrates EU shipping carbon tax policies with projections of green methanol economics, incorporating technical parameters for port-based in-situ methanol production systems to simulate the synergistic effects of policy reinforcement and technological cost reductions on ESG financial returns. The findings reveal that, in the short term (2023~2025), green methanol vessel retrofits lead to a decline in ROA, though ESG rating improvements generate implicit benefits. In the long term, post-2030, as carbon tax costs rise and green methanol costs decline, the ESG return curve exhibits “exponential growth,” with ROA surpassing the baseline scenario by 2035. The study proposes a “fuel substitution-carbon tax savings” financial compensation mechanism, providing quantitative decision-making support for shipping companies’ ESG investments and policy formulation.