Reducing carbon emission by optimizing container liner fleet deployment and sailing speed

Facing stringent environmental regulations and an aging fleet, container liner shipping companies face mounting pressure to reduce fuel consumption and emissions. This paper optimizes tactical fleet deployment and sailing speed by explicitly incorporating vessel heterogeneity. A mixed integer nonlinear programming model is formulated, and a Velocity-Discretization-Based Dynamic Algorithm is developed to improve computational efficiency. Practical fleet adjustment constraints are further considered to evaluate the achievable benefits under limited vessel redeployment. Numerical experiments based on real-world operational data demonstrate that considering vessel heterogeneity and jointly optimizing deployment and speed can significantly reduce fuel consumption and CO 2 emissions. The proposed algorithm achieves reliable solutions with substantially shorter computational time than the direct solution, providing a practical decision-support tool for sustainable liner shipping operations.