Off-Design Performance Analysis of a Hybrid System Based on an Existing MCFC Stack

This paper addresses the off-design analysis of a hybrid system (HS) based on the coupling of an existing Ansaldo Fuel Cells (formerly Ansaldo Ricerche) molten carbonate fuel cell (MCFC) stack (100 kW) and a micro gas turbine. The MCFC stack model at fixed design conditions has previously been presented by the Authors [1]. The present work refers to an off-design stack model, taking into account the influence of the reactor layout, current density, air and fuel utilisation factor, CO₂ recycle loop, cell operating temperature, etc. Finally, the design and off-design model of the whole hybrid system is presented. Efficiency at part load condition is presented and discussed, taking into account all the constraints for the stack and the micro gas turbine, with particular emphasis on CO₂ recycle control.