E-methanol conversion and pooling strategies for maritime compliance under EU carbon regulations

Decarbonisation in the maritime sector requires not only technological innovation but also economically viable compliance strategies under increasingly stringent regulatory frameworks. This study evaluates the technical and economic implications of e-methanol-based fuel conversion combined with pooling mechanisms under FuelEU Maritime and the EU Emissions Trading System (EU ETS). A five-vessel containership fleet is analysed within a scenario-based framework, where one vessel is converted to e-methanol while the others continue operating on conventional fuels. The results indicate that the converted vessel may generate an average annual compliance surplus of approximately 1,800 tonnes of CO₂eq, enabling fleet-level compliance and producing total incentive revenues of USD 9.34 million. The conversion investment of approximately €5.77 million is estimated to be recovered within 14 years. Regulatory costs are projected to increase from approximately 25% to 65% of total fleet costs, reflecting a shift toward compliance-driven cost structures. The findings suggest that selective fuel conversion combined with regulatory flexibility may offer a cost-effective transitional pathway. However, the results are scenario-dependent and sensitive to key uncertainties, including fuel prices, carbon pricing, and policy developments.