Performance evaluation of a novel photovoltaic-thermochemical and solid oxide fuel cell-based distributed energy system with CO2 capture

Efficient energy utilization and decarbonization of energy systems are of paramount importance in tackling global climate change. A novel distributed energy system is proposed, integrating solar photovoltaics, methanol thermochemistry, solid oxide fuel cells, gas turbines, and CO2 capture. Methanol is reformed by photovoltaic waste heat to produce solar hydrogen-rich syngas, which is then efficiently converted to electricity by solid oxide fuel cells. High-purity CO2 is separated from the anode exhaust gas containing only CO2 and H2O through low-energy penalty separation via condensation of H2O, and is subsequently compressed for storage. Analysis demonstrates that the proposed system outperforms the reference system with parabolic trough solar collectors. The total electrical efficiency of the new system reaches 51.73%, surpassing that of the reference system by 5.02 percentage points, while solar-to-electricity efficiency improves by 19.69%. The overall exergy efficiency of the proposed system reaches 57.41%. The levelized cost of electricity and cost of CO2 avoided for the proposed system are 0.1163 $/kWh and 29.87 $/t, respectively, and the dynamic payback period is only 4.5 years. Sensitivity analyses indicate outstanding power generation performance, excellent CO2 reduction potential, and wide adaptability for regional applications.