Abstract: The combination of renewable energy utilization and carbon capture technology is one of the development directions of low-carbon energy systems in the future. Among them, solar-driven methanol reforming decarbonization and hydrogen production can achieve efficient conversion and utilization of solar energy, hydrogen storage and transportation, and carbon capture. Collaborative development has important research significance. However, the current research mainly focuses on the combination of solar thermal energy utilization and methanol reforming decarbonization for hydrogen production. The cascade integration of solar spectral quality utilization and methanol reforming decarbonization process has not been realized, resulting in the difficulty of greatly improving the overall energy efficiency of the system. In this study, a methanol reforming-decarbonization-hydrogen co-generation system based on spectral frequency division technology is proposed to realize the high energy integration of solar energy full spectrum utilization and methanol reforming, carbon capture, waste heat refrigeration and other units, and realize the cascade utilization of system energy grade and low energy consumption decarburization. The analysis shows that compared with the current conventional carbon capture related systems, the energy efficiency and exergy efficiency of the new system proposed in this study are 74.7% and 72.5%, respectively, which is 8.3% higher than that of the reference system without deep synergistic carbon capture. The exergy analysis shows that the exergy efficiency of the new system is 72.5%, which is 8.0% higher than that of the reference system without deep synergistic carbon capture. The core reason for the significant reduction of exergy loss is that the spectral frequency division technology effectively reduces the irreversible loss of energy conversion by 23.3%. The analysis of variable operating conditions shows that the system can operate stably under typical sunny conditions in spring, summer, autumn and winter to ensure the continuity and stability of the carbon capture process. However, under the weather of continuous rain and extremely low irradiation, the system cannot meet the operating threshold, and auxiliary energy is needed to ensure the stable promotion of carbon capture. Economic analysis shows that under the premise of achieving the same energy output and carbon capture target, the area of solar mirror field required by spectral frequency division technology is about 39.8% lower than that of single photovoltaic or photothermal conversion mode, which greatly reduces the system land occupation cost and carbon footprint. In the case of the same product output and the same carbon capture effect, the new combined production system can save 15.9% of the investment compared with the current conventional carbon capture related reference system, taking into account the low-carbon benefits and economic performance. The co-production scheme proposed in this study provides a new technical path for solving the coordinated development of efficient solar energy utilization, clean hydrogen supply and carbon emission reduction.