Application oriented multiple-objective optimization, analysis and comparison of solid oxide fuel cell systems with different configurations

Abstract

With the development of SOFC (solid oxide fuel cell) technology, especially in terms of cell manufacture and stack assembly, recent SOFC research has focused on system integration and control. Various SOFC system configurations presented in the literature can be applied to various application scenarios for their unique advantages. A thorough evaluation and comparison of those SOFC systems in terms of performance, cost and efficiency is very important for optimal system design, taking the environment and conditions into consideration. In this paper, four typical 10 kW-scale SOFC-based systems are investigated, a hydrogen-fueled SOFC system, an external steam-reforming SOFC system, an SOFC/gas turbine hybrid system and SOFC/SOEC (solid oxide electrolysis cell) combined system. First, physical system models were constructed according to physical conservation laws and chemical kinetics and validated using experimental data. In addition, an exergoeconomic analysis was carried out based on these models. Then the optimal operating points of the four systems, which can be used for system performance comparison under the same operating conditions, are acquired through a multiple-objective optimization process based on an improved genetic particle swarm optimization algorithm. Then the systems were compared in aspects of technical and exergoeconomic performance under the same net output power, and comprehensive system marking was performed. Finally, analysis and predictions of application scenarios for these systems were proposed based on the scores. This paper provides a theoretical foundation for the design, analysis and application of SOFC systems.