Exergy Analysis and Optimization of Gasifier-Solid Oxide Fuel Cell-Gas Turbine Hybrid System

In this paper, different systems based on integrated gasifier-solid oxide fuel cells (SOFC)-gas turbine hybrid system are modelled to carry out their thermodynamic analysis. The thermodynamic flowsheet software Cycle-Tempo is used to analyze the performance of the modelled systems. Influence of fuels viz. coal and cow manure on the performance of the integrated hybrid system is studied. It is observed that the efficiency of the system changes with change in fuel. The electrical efficiency is found to be 40.2% when coal was used as fuel, and the efficiency increased to 48.2% when coal was replaced by cow manure as fuel. Exergy analysis of the integrated hybrid base case system is performed to find out the components responsible for the poor efficiency of the system. Based on the exergy analysis of the base case system, a new optimized system was designed with the critical operating parameters remaining the same. The system efficiency increased from 40.2% to 49% with coal as fuel and from 48.2% to 56.9% with cow manure as fuel in the optimized system. Exergy analysis of the optimized system depicts that there is a reduction in total relative exergy loss percentage when compared to the base case system.