Multi-Scale Analysis of Solid Oxide Cells for Energy Applications: Experimental Characterization and System-level Simulation

In this work different aspects of SOCs (mostly in SOFC mode but also in SOEC and rSOC modes) are analysed with a multi-scale analysis approach, from cell to system level. According to the scale it is possible to analyse representative aspects of the technology at that specific domain, with focus on experimental studies at smaller scales – which is the main element of novelty of this work, respect to typical theory-driven multi-scale modelling approaches. At button-cell level the SOC physico-chemical processes can be identified and parametrized with impedance-based methods; at single-cell level the electrochemical performance and gas conversion is studied with polarization approaches and gas chromatography analyses in different operating conditions. Instead, at short-stack level the output power and efficiency maps can be obtained of the stable operation points in different conditions. The experimental analyses are carried out in the framework of different EU research projects (qSOFC, BLAZE, W2W, SO-FREE), which set the specific requirements and boundaries of the specific experimental campaigns which are reported in this work. Only at system scale the actual rSOC system is analysed coupled to RES in two different applications: in case study 1 the rSOC system is evaluated coupled to an offshore wind turbine for back-up power and hydrogen production and in case study 2 the rSOC integration in building energy systems in the residential sector is analysed, with parametric analysis according to the building type (apartment/villa), climate zone and reference year of construction of the building stock. The system integration analyses are based on a rSOC component model which leverages the experimental stack-level datasets of a stack which is integrated into an actual commercial rSOC system prototype, typically used as smart energy hub for energy storage and poly-generation solutions, in order to provide a more realistic system level output which takes into account the real operating conditions of the rSOC system as well as the actual processes occurring internally to the system, respect to most black-box approaches used in system integration modelling studies.