Energy Management for Ship-Integrated Energy System Considering Carbon Emission Intensity Grading Mechanism with EEOI

In the context of escalating global carbon emissions and rising costs of traditional fossil fuels, the singular reliance on fossil fuel-based equipment for energy supply is no longer sustainable. Consequently, an integrated energy system incorporating both renewable energy sources and conventional fossil fuel equipment, known as the Ship-Integrated Energy System (S-IES), has emerged. As a novel ship energy architecture, the S-IES enables the efficient synergistic utilization of heterogeneous energy sources. To ensure the safe, reliable, and green operation of the S-IES, an energy management model is first established. This model facilitates the synergistic optimization of economic and environmental performance during voyages, namely, the minimization of operational costs and total carbon emissions. Furthermore, to quantify the carbon reduction effectiveness of the constructed energy management model and to align with the carbon emission reduction regulations for the shipping industry drafted by the International Maritime Organization (IMO), this paper establishes a ship carbon emission intensity grading mechanism based on the Energy Efficiency Operational Indicator (EEOI). This mechanism quantifies the carbon emission intensity throughout the entire voyage, contributing to reduced total ship carbon emissions while, to a certain extent, safeguarding the economic benefits of shipowner. Finally, the effectiveness of the proposed S-IES energy management model and the carbon emission intensity grading mechanism is validated using the fundamental data of a bulk carrier as a case study.