Performance and application assessment of fuel cell-engine-organic Rankine cycle power generation system with methanol for ship

The current ship power system has problems of low efficiency and high carbon emissions. This paper proposes a methanol-based fuel cell-engine-organic Rankine cycle (ORC) power generation system. The fuel cell adopts two types: solid oxide fuel cell (SOFC) and high-temperature proton exchange membrane fuel cell (HT-PEMFC). A modular modeling approach is employed to analyze the performance and exergy utilization of the hybrid power generation system. The study also investigates the impact of various parameters on the system's performance, including excess air ratio, fuel utilization, and conducts an applied assessment of the hybrid power system. The results indicate that the electrical efficiency of the SOFC hybrid power generation system reaches 58.37 %, approximately 20 % higher than the HT-PEMFC hybrid power system. In the HT-PEMFC system, the fuel cell is identified as the component with the highest exergy destruction, while in the SOFC system, the air heat exchanger and engine contribute significantly to exergy destruction. The power density of the SOFC hybrid power system is observed to be 25W/kg, approximately one-fourth of the HT-PEMFC system and engine system. And the carbon emissions generated by the system are significantly lower than those from the current power systems.