Integrated analysis and performance optimization of fuel cell engine cogeneration system with methanol for marine application

Abstract

To achieve environmental sustainability and low carbon emissions in the field of marine power systems, it is crucial to enhance system performance in both the fuel subsystem and power subsystem. This study introduces a solid oxide fuel cell (SOFC) engine cogeneration system utilizing methanol fuel designed specifically for marine applications. Methanol serves as a hydrogen source for the SOFC through online reforming, producing hydrogen. The engine further enhances energy efficiency by utilizing the anode tail gas from the SOFC. The study employs the energy, economy, and environment (3E) analysis method to assess the system's performance. Results demonstrate that the system exhibits high energy efficiency and low carbon emissions. The system configuration is optimized, and design points are determined through parameter optimization. The rated power generation efficiency of the system can reach 59.57 %, which is nearly 20 % absolute efficiency improvement compared to methanol engines. An analysis of the system's performance under partial load conditions reveals that, even at 53 % load, the power generation efficiency remains at 53.29 %. The total life cycle carbon emissions for the system is 319.78 g/kWh, significantly lower than the engine. The levelized cost of energy for the system are 0.1161 $/kWh, slightly higher than engine power generation costs.