Energy and configuration management strategy for solid oxide fuel cell/engine/battery hybrid power system with methanol on marine: A case study

The adoption of alternative fuels and high-efficiency power systems has the potential to significantly reduce carbon emissions in maritime transportation. However, there is currently limited understanding of how new power forms affect the effective payload during actual ship operations. This study proposes a hybrid power system using methanol as fuel, integrating solid oxide fuel cells, an engine, and batteries. A mathematical model of the system was established using a modular modeling approach, and the system's performance was evaluated based on container ship scenarios. The results demonstrate that under no-refueling conditions, the hybrid power system achieves a high electrical efficiency of 58.36 %, a fuel consumption rate of 283.19 g/kWh, and carbon emissions of 389.39 g/kWh. Increasing the operating temperature and reducing the current density can enhance the thermodynamic performance of the solid oxide fuel cell and the system, with electrical efficiency exceeding 60 %. Solid oxide fuel cells exhibit poor load variation characteristics, taking approximately 200 s for their output voltage to decrease from 0.62 V to 0.57 V. In contrast, lithium batteries demonstrate rapid load response characteristics. For a single voyage, the ship requires 835.776 tons of fuel, resulting in an increase of 284.776 tons compared to diesel engines. However, carbon emissions are reduced by 606.46 tons. It is noteworthy that the weight and volume of the hybrid power system depend on the power distribution between the fuel cell and the engine. In summary, this innovative hybrid power system provides a potent means of significantly reducing carbon emissions in the shipping industry.