Fuel sensitivity and parametric optimization of SOFC – GT hybrid system operational characteristics

Abstract

The primary objective of this research is to analyze the effects of different fuels on the various performance characteristics of solid oxide fuel cell – gas turbine (SOFC – GT) hybrid systems and to optimize said component parameters based on relevant thermodynamic models. The hybrid system presented is that of a pressurized configuration containing a high temperature SOFC as well as a recuperator. For comparison, methane (CH4), carbon monoxide (CO) and hydrogen (H2) are used to power SOFC – GT systems respectively, and when the system is fueled by CH4 or CO, a reformer is also included in the system configuration. Results highlight the influence of different fuels and content on achievable operating range of SOFC and reformer temperature as well as on operating pressures; the system performance is also studied and compared in terms of potentials, electricity output, energy and exergy efficiency, etc. within the allowable range of parameters. It has been observed that the hybrid system reaches an optimized electric efficiency of 56.1%, 54.3% and 60.7% when fueled by CH4, CO and H2 (96 vol%) respectively based on this basic configuration proposed.