The lack of accurate modeling of solid oxide fuel cells (SOFC's) and their systems has resulted in limitations in identifying key operating parameters and allowing for system configuration. The purpose of this study is to address each level of modeling needed to identify key parameters as well as integrating each level of modeling. The first level deals with the single cell and its electrochemical and thermal issues. The second level deals with the bundling of cells to form an SOFC stack while the third level incorporates the stack results into an overall thermal system.