Integrated approaches that combine numerical modeling and economic evaluations were developed to investigate the potential widespread use of integrated solid oxide fuel cell (SOFC) systems. A coupled model analysis of the cell performance and production costs of a segmented-in-series tubular solid oxide fuel cell (SST-SOFC) system was performed for a combined cycle power generation system integrating an SOFC and a gas turbine. The SST-SOFC cell-stack performance was investigated using a finite element method (FEM), and cost analysis of the SST-SOFC module production was conducted based on process-integration modeling. The impact of the cell-stack dimensions and material properties on the cell stack performance was evaluated using FEM-based numerical modeling simulation. Cost analysis was performed in terms of cell dimension, the production process, and cell performance, based on the results of the FEM-based model simulation. We used a 250 kW combined cycle system, i.e., a 220 kW SST-SOFC module with a 30 kW micro gas turbine, to explore quantitative technological innovation pathways. The base-case production cost was ca. 240 JPY/W (ca. 2.4 USD/W), which can be reduced to ca. 110 JPY/W (ca. 1.10 USD/W) by increasing the production scale. In addition, the present method showed the innovation pathway to achieve a break-even point for grid electricity cost (14 JPY/kWh (0.14 USD/kWh)). (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.