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The EU Integrated Project Real‐SOFC aims at improving the understanding of degradation in SOFC stacks, and extending the durability of planar SOFC stacks to degradation rates suitable for stationary application. As part of the Real‐SOFC project, three series of SOFC stacks, each with two or four planar anode‐supported cells, were operated for durations of 3,000 h up to 10,000 h under varying fuel and electrical load conditions. The durability tests on these short stacks were conducted galvanostatically at 800 and 700 °C in dependence of current‐density (0.3, 0.5 or 0.7 A cm–2), of fuel composition (hydrogen: H2 + 3–10% H2O or methane: CH4/H2O (S/C = 2)) and of fuel utilisation (8, 40, 60 or 75%). A pronounced difference in degradation behaviour was observed between the stacks operated at different current densities. The degradation behaviour was, however, not influenced by the choice of fuel (hydrogen or methane) and was hardly influenced by the fuel utilisation. Lowest degradation rates of about 20 mΩ cm2 kh–1 were determined for the tests of a short stack with cells with LSM cathodes operated at 800 °C and a current‐density of 0.3 A cm–2 and of a short stack with cells with LSCF cathodes operated at 700 °C and a current‐density of 0.5 A cm–2. Post‐test characterisation of the cathode with respect to chromium poisoning was performed on cells from several stacks. No clear relationship between the degradation rate of the stacks and amount of Cr incorporated in the cathode could be established. The major difference was a change in microstructure of the cathode in the region near the electrolyte interface; in the stacks operated at lower current densities, the structurally changed zone was clearly thinner than in those stacks operated at higher currents.

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A dynamical model for a 5kW class solid oxide fuel cell (SOFC) combined heat and power (CHP) test station has been composed using the APROS® environment. The model is based on a real test station being constructed and operated at VTT Technical Research Centre of Finland and it comprises the following main components of the real test system: the autothermal reforming unit, SOFC stack situated inside a furnace, catalytic afterburner, and three heat exchangers. The constructed model has been verified against experimental results obtained from the autothermal reforming unit, catalytic afterburner, and the two cathode side heat exchangers. The model has been used for the phenomenological studies of the system during current transient simulations using a simplified and fast zero-dimensional model including internal reforming reactions for the SOFC stack. The test station model was capable of operating at a speed of 18 times the real time using a standard personal computer.