Solid oxide fuel cell performance analysis through local modelling

Abstract

Solid Oxide Fuel Cells (SOFC) are an emerging technology among different fuel cell types since they are successfully used in stationary cogeneration units to produce heat and electricity. Different scale applications are proposed as alternative energy sources for residential usage and industrial power plants, reducing the greenhouse gas emissions which characterize fossil-fuel-based processes. Their spread is favoured by the development of proper simulation tools that allow system design optimization and control in real-time operations. For this purpose, model building and validation, through comparison with experimental observations, are fundamental steps to guarantee the simulation validity. A single-anode-supported planar SOFC with two possible cathodic current collector designs is tested in common operating conditions, evaluating the performance through EIS analysis and characteristic curves. These provide a preliminary validation for the proposed 2D steady state simulation code. This model, implemented in Fortran, makes it possible to forecast the main SOFC local properties on both the anodic and cathodic sides. The key point of the code is the electrochemical kinetics, based on a semi-empirical approach where requested parameters, derived from fitting of experimental results, are introduced in physically based equations. In this way, the influence of specific cell design on system performance is evaluated.