A hybrid system integrating solid oxide fuel cell and thermo-radiative-photovoltaic cells for energy cascade utilization

Abstract

A novel hybrid system coupling solid oxide fuel cell (SOFC) with thermoradiative (TR) and photovoltaic (PV) cells is proposed, evaluated, and optimized for energy cascade utilization. Theories of electrochemistry, Planck radiative heat transfer, and first law of thermodynamics are applied to assess and optimize the performance of the hybrid system. Firstly, energy balance analysis is conducted to obtain suitable area ratio between the subsystems and the SOFC. A homo-structure InAs–InAs is chosen as an example of the TP-PV cells. The peak power density of 0.669 W cm−2 and the maximum efficiency of 0.770 and the relevant work conditions are achieved through parametric optimal analysis. It is also found that decreasing the leakage resistance of the SOFC can enhance electricity production and efficiency of the hybrid system. Secondly, a GaSb-InSb TP-PV cells are adopted to couple with the SOFC for performance enhancement. Finally, the positive effects of back surface reflector and the negative effects of irreversible heat transfers on the hybrid system are discussed. The obtained results are helpful for designing and optimizing the SOFC-TR-PV hybrid systems.