Integrated Power Generation System Of "Photovoltaic, Thermal And Storage" Based On CAES

China’s primary energy is mainly coal.For a long time,coal power still needs to play the role of basic power supply.To achieve the“double carbon”goal and reduce CO₂ emissions,it is particularly important to build a new generation system on the basis of coal-fired power.The scheme of coupling coal-fired power with the solar photothermal system has been proposed and shows good prospects,while the coal-fired power coupled with compressed air energy storage ha s shown great potential in recent years.Therefore,this paper proposes photothermal energy storage integrated power generation system coupled with a compressed air energy storage system,solar thermal system,and coal-fired power,and analyzes the thermal characteristics and economy of the system i n depth.The design scheme of a“solar,coal-fired power and energy storage”integrated power generation system is proposed.To realize the flexible operation of the integrated power generation system,five operation modes are formulated for this scheme,namely,the independent operation of the coal-fired power,the coupled operation of the trough solar system and the coal-fired power,the coupled operation of the trough solar system with heat storage and the coal-fired power,the coupled operation of the compressed air energy storage system and the coal-fired power,and the operation mode of the integrated power generation system with photo-thermal energy storage.Different operation modes switch through the valves on the connecting pipes between the systems.Taking a 350MW coal-fired power as the research object,the operation strategy of night-time constant power and day-time constant coal consumption is adopted,and the model of the integrated“solar,coal-fired power and energy storage”power generation system is established by using Ebsilon software.The performance of different operation modes of the coal-fired power under 100%THA working conditions is simulated.The results show that the standard coal consumption rate and heat consumption rate of Mode2 and Mode3 for energy storage are reduced;mode4 and Mode5 turn on the energy storage,due to the storage of part of the electricity,the thermal performance is slightly worse,but the peak shaving ability of the system is greatly improved.The operation characteristics of an integrated power generation system for coal-fired power under 100%,75%,50%,and 40%THA loads are studied.The results show that the performance improvement is more obvious at low load;in the process of load reduction,Mode5 has the best effect on peak load regulation,energy conservation,and emission reduction.The peak load regulation capacity is high and flexible,and it has the ability of upward and downward peak load regulation.Although the thermal performance has been lost,it is better than that of the original coal-fired power.The compensation income of Mode5 for peak load reduction at 40%load is as high as CNY 255.1 million,which proves that the operation of energy storage greatly increases the income of an integrated power generation system.Typical days were selected in spring,summer,autumn,and winter to compare and analyze the performance of the integrated power generation system.The results show that the performance changes obviously when the season changes.The performance is the best in June（summer）and the worst in December（winter）.Seasonal changes have a greater impact on t he performance of Mode2and Mode3,while Mode4and Mode5are relatively stable,which proves that the presence of energy storage can reduce the impact of solar randomness on the system.From an economic point of view,in December,due to poor solar energy resources,the income is low.In the season of lack of solar resources,an appropriate operation mode can be selected to solve the problem of insufficient solar energy in winter.Taking Hainan,Yulin,and Changchun as representative regions,the performance of the integrated power generation system of’light,fire,and storage’in different regions is compared and analyzed.By comparing the performance of integrated power plants in different regions,it can be seen that the performance change is affected by the locally available radiation energy.The annual performance of Hainan and Yulin is similar and superior,and the overall performance of Changchun is poor.Hainan has the best performance in March,June,and December,and Yulin has the best performance i n September.Hainan has stable performance throughout the year,and Yulin has the best solar energy resources in summer.So,Hainan and Yulin are suitable for building integrated power generation systems.