Alternative designs of planar solid oxide fuel cell stack have been developed over the last decade. Depending on the application, different geometries, materials and flow configurations were adopted. This study investigates a generic solid oxide fuel cell stack with nominal power output above 1.3 kWel. The fuel cell stack is a key component of a highly integrated micro-cogenerator for domestic application. As daily, weekly and monthly variations in the electrical power load are expected, there is a need to develop numerical tools to predict the units performance with high accuracy. Hence, a fully physical dynamic model of a SOFC stack was developed and implemented in Aspen HYSYS 7.2 modeling software to enable predictive analysis of the off-design operation. The presented model exhibits high accuracy and accounts for thermal and electrochemical processes and parameters. The authors present the methodology used in the study to analyze the sensitivity of key parameters to load changes in cross-, co- and counter current flow configuration in the stack. Further functionality of the model, which was validated using manufactures data is discussed. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.