A sunlight driven multi-energy complementary utilization system based on concentrating spectral beam splitting strategy is proposed for CO2 recycling. The high-energy shortwave part of solar spectrum is converted into electricity by photovoltaic cells to activate water electrolysis reaction for H2 production, while the residual energy is transformed into heat by an evacuated heat-collecting tube to trigger the decomposition of saturated CO2 adsorbents. Subsequently, the released CO2 reacts with the previously generated H2 to form fuel, realizing autothermic CO2 conversion. Thermodynamic analysis of this model system reveals that the optimized solar-to-methane efficiency and heat-collecting efficiency could reach up to 8.08% and 68.79% respectively, when the splitting waveband for photovoltaics-water electrolysis is 600-900 nm. The current work provides a viable solution for the short-term implementation of solar-driven CO2 conversion technology into large-scale energy markets.
Keywords Full spectrum utilization, carbon dioxide conversion, splitting waveband, solar-to-fuel efficiency