A rolling multi-objective ship speed optimization strategy for energy efficiency and operating cost control in dynamic waterway conditions

Abstract

The push to decarbonization for ships is driving the development of supporting tools for operations. This study develops a rolling, voyage-scale multi-objective decision-support framework for speed management on inland waterways. The framework simultaneously minimizes the Energy Efficiency Operational Indicator (EEOI) and total operating cost by adjusting ship speed leg by leg under time-varying environmental conditions. Within each decision window, it solves a nonlinear bi-objective optimization problem using updated environmental and operating information to generate a practical compromise speed recommendation. A case study on a 7000 t bulk carrier across 18 legs shows that, compared with as-operated records, the proposed framework lowers total cost by 7.5% and shortens voyage time by 9.5%, while producing a smoother speed profile that is more compatible with ship propulsion and power-system control. These results indicate that rolling multi-objective speed optimization offers an effective engineering approach for voyage planning and operational speed management under time-varying environmental conditions, with clear potential for inland waterway decision-support applications.