Modelling of a hybrid system for on-site power generation from solar fuels

Abstract

Solar fuels, as clean and sustainable fuels, are promising energy sources for future low carbon economy. In this work, a hybrid system consisting of a photoreactor and a solid oxide fuel cell (SOFC) is proposed for on-site power generation from solar fuels. 2D numerical models are developed for the hybrid system for the first time by coupling the mass/momentum transport with the charge (electrons/ions) transport and the electrochemical/chemical reactions. A peak power density of 2162 W m −2 is achieved from the SOFC at 1073 K operating temperature. However, a rapid drop of the power density is observed at large current density due to the fuel starvation in the anode. The inlet CO 2 mole fraction is found to significantly affect the output power density of the SOFC and CO 2 utilization rate of the photo reactor, where a CO 2 mole fraction of 40% is the optimum value for the studied cases. The results offer insightful information on energy conversion from solar to fuel to power and provide new options for sustainable energy conversion devices.