用于发电、储能与调峰的综合能源系统热力学与经济性分析

Abstract The current global energy landscape is undergoing significant changes. The high consumption of traditional energy sources not only depletes reserves rapidly but also leads to various environmental issues. As a result, renewable and clean energy sources are gaining increased global attention. In this work, we propose an integrated system that encompasses power generation , energy storage, and peak shaving functionalities. The system utilizes heat from solar energy and renewable electricity that needs to be consumed. Solar energy is stored in molten salt and then provided to the supercritical carbon dioxide (sCO 2 ) circulation system for power generation. The system simultaneously utilizes CO 2 and H 2 to produce methanol, which serves as a means of energy storage. The gas-steam turbine combined cycle (GTCC) utilizes methanol as fuel for power generation during peak demand periods. The flue gases produced in this process are treated by a flue gas treatment unit, which captures CO 2 and repurposes it as raw material for methanol synthesis. Additionally, electrolyzed use electricity generated by wind and solar power to split water into hydrogen and oxygen. The hydrogen produced is then used as a raw material for methanol synthesis, while the oxygen can be sold as a by-product. The integrated energy utilization system is designed to discharge electrical power at a capacity of 15 MW. Through thermodynamic and economic analysis, the integrated system demonstrates energy utilization efficiencies of 26.3 % at 100 % load of full system and 37.9 % at 30 % load of GTCC, along with exergy efficiencies of 34.8 % and 49.5 %, respectively. The investment payback period for this system is 15.8 years. The energy comprehensive utilization system developed in this study achieves a closed-loop conversion of “solar, heat, electricity, hydrogen, and carbon.” It showcases significant advantages such as zero carbon emissions and a green, clean profile, indicating strong development prospects. This work can offer valuable guidance and suggestions for constructing new systems in the future energy sector.