Exergetic and exergoeconomic evaluation of an SOFC-Engine-ORC hybrid power generation system with methanol for ship application

Abstract

The SOFC-Engine hybrid system is considered suitable as a marine power system due to its impressive attributes, including high efficiency and effective adaptability to variable loads. Combined with the ORC system and methanol fuel, the system's efficiency and carbon reduction can be taken to the next level. This study introduces a novel solid oxide fuel cell (SOFC)-Engine-Organic Rankine cycle (ORC) hybrid power generation system that operates on methanol. Rigorous assessments were conducted utilizing energy analysis, exergetic analysis, and exergoeconomic analysis. These evaluations aimed to pinpoint precise strategies for enhancing system efficiency while curbing expenses. The results show that the power generation efficiency of the hybrid system is 61.86%, and the exergy efficiency was 58.06%. Notably, the air preheater and engine emerge as components causing substantial exergy losses. Through exergoeconomic analysis, the exergy cost distribution across all system parts was unveiled. The reformer's exergoeconomic factor registers the highest at 77.62%. Consequently, mitigating the exergy cost associated with the reformer holds paramount importance in augmenting overall system revenue. Remarkably, the engine incurs the highest cost of exergy destruction at 10.134 $/h. Overall, this research offers pivotal insights for optimizing component performance and driving cost reductions.