Design of an SOFC/SOE experimental station: Planning of simulation tests

At the University of Calabria at the Department of Mechanical, Energy and Management Engineering, an SOFC-SOE experimental station was built for the generation of electrical and thermal energies and for the production of hydrogen - carbon monoxide and oxygen. In SOFC mode the station is fed by mixtures rich in H2 with CO2, CO, N2, while in SOE mode the two configurations are foreseen: in electrolysis for H2 production and in co-electrolysis for the production of H2-CO mixtures. The SOFC-SOE test bench includes a short stack, with an attached electrochemical device setup, a furnace for the control of temperature and a reforming reactor for the possible conversion of CH4 into a hydrogen-rich stream. The station is also equipped with a steam generator, an electronic load for the consumption of the station electrical power (SOFC mode) and a power supply for the supply of electrical power to the short stack (SOE mode). This work presents the design activity, focused on the sizing and selection of the components with which to equip the station, such as: the air compressor, the sensors and the gas distribution system. The procedure, followed to arrive at an adequate management of the gas stocks used, is also illustrated. The experimental test campaigns were planned with reference to the various gaseous mixtures to be simulated and with reference to the control strategy of the most significant parameters, both for SOFC and SOE mode. Starting from a preliminary analysis on the carbon deposition phenomenon, the gas mixture implying a safe functioning of the fuel cell was identified in terms of H2/CO ratio. In addition, the steam to carbon ratio to improve the mixture and its safe operation was found out in the planning stage. As for the storage, a preliminary design was done to determine the useful gas volume to be equipped with, consequently the number of cylinders to manage in the subsequent simulation-experimental campaigns.