The international shipping industry has prioritized emissions reduction and invested in green shipping technologies. Shipping alliances have also significantly transformed market structure of container shipping industry, resulting in increased market power for major alliances in recent years. These strategic alliances have substantial implications for the economic incentives to invest in green shipping technologies. This study examines the impact of shipping alliances on green shipping investment by constructing an economic model comprising a port, two shipping lines, and government authority. The analysis demonstrates that shipping alliances promotes green shipping investments, even with increased shipping traffic, leading to an overall reduction in emissions. While these alliances improve shipper surplus, the enhancement of social welfare depends on whether cost savings from reduced emissions outweigh higher investment costs associated with green shipping. Endogenizing emission tax results in lower social-optimal emission tax, which drives more shipping traffic, offsetting emissions reduction from increased green shipping investment.

中文翻译：

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航运联盟会促进还是阻碍绿色航运投资？

国际航运业优先考虑减排并投资绿色航运技术。近年来，航运联盟也显着改变了集装箱航运业的市场结构，导致各大联盟的市场力量不断增强。这些战略联盟对于投资绿色航运技术的经济激励具有重大影响。本研究通过构建一个由港口、两条航运公司和政府机构组成的经济模型，探讨航运联盟对绿色航运投资的影响。分析表明，即使航运量增加，航运联盟也能促进绿色航运投资，从而整体减少排放。虽然这些联盟改善了托运人盈余，但社会福利的提高取决于减少排放所节省的成本是否超过与绿色航运相关的更高的投资成本。内生排放税导致社会最优排放税降低，从而带动更多航运量，抵消了绿色航运投资增加带来的减排量。