Integrated Intelligent Energy ›› 2026, Vol. 48 ›› Issue (5): 83-94.doi: 10.3969/j.issn.2097-0706.2026.05.009

• Integrated Energy System Analysis and Evaluation • Previous Articles    

Economic efficiency analysis of operation strategies for the solar-coal peak-shaving system with steam extraction and molten salt thermal energy storage based on wind and solar power integration amount

CUI Yarua,b(), LU Yuanweia,b,*(), WANG Zixuana,b(), YANG Hana,b(), WU Yutinga,b()   

  1. a.Beijing Key Laboratory of Heat Transfer and Energy Conversion;b.National User-Side Energy Storage Innovation Research and Development Center,Beijing University of TechnologyBeijing 100124, China
  • Received:2026-01-09 Revised:2026-02-26 Published:2026-04-14
  • Contact: LU Yuanwei E-mail:cuiyaru@emails.bjut.edu.cn;luyuanwei@bjut.edu.cn;zixuanwang@emails.bjut.edu.cn;yanghan@bjut.edu.cn;wuyuting@bjut.edu.cn
  • Supported by:
    National Key R&D Program of China(2022YFB4202402)

Abstract:

To solve the problem of coordinating peak-shaving flexibility and economic efficiency of coal-fired units under the background of high-proportion wind-solar power integration, 600 MW subcritical coal-fired units were taken as the research object, and a deep peak-shaving system with solar-coal coupling based on steam extraction and molten salt thermal energy storage was proposed. In view of the limitation that existing research fails to fully consider the interaction between wind and solar power integration amount and the operation strategies for the peak-shaving system, a life-cycle cost system covering initial investment, operation and maintenance, and coal cost was established. Additionally, an economic model was established with net present value, dynamic investment payback period, levelized cost of electricity, and wind and solar power curtailment as evaluation indicators. Combined with wind and solar output curves and daily load curves, seven differentiated operation strategies were designed, and their multi-dimensional performance was comprehensively optimized and selected using the entropy weight-TOPSIS method. The results showed that strategy 1 was optimal for comprehensive performance. By precisely matching the thermal energy storage timing of high wind and solar power output with low load periods, strategy 1 achieved the triple advantages of a net present value of 1.807 1×109 yuan, a dynamic investment payback period of 7.424 a, and wind and solar power curtailment of 2 090 MW·h. The system output power closely followed the daily load curves, and the wind and solar power integration ratio reached 72.54%.

Key words: molten salt thermal energy storage, solar-coal coupling, deep peak shaving, wind and solar power integration, operation strategies, entropy weight-TOPSIS method, economic efficiency

CLC Number: