Flexible operation performance analysis of coal-fired power plant coupled solar thermal energy storage and compressed air energy storage

This paper proposes a novel “solar-fired-storage” integrated power generation system and its operational strategy, which combines solar energy, thermal energy storage (TES), a coal-fired power plant (CFPP), and a compressed air energy storage (CAES) system to improve the operation flexibility of the CFPP. The solar thermal system enhances the thermal performance by reducing CFPP coal and heat consumption rate, while the CAES system improves the system peak regulation capability. The thermodynamic performance of the integrated power generation system is investigated across different seasons and regions. The results indicate that the integrated power generation system has stable seasonal adaptability in typical regions, despite variations in seasonal characteristics. Especially in summer, the system has a peak regulation depth ranging from -2.76% to 3.97%, coal saving of 9.40t, and CO 2 emission reduction of 26.59t. By comparing the system performance in different regions (three regions within China are selected), it is found that system performance is affected by local solar radiation availability. Yulin shows superior annual average performance, and both the average daily coal saving and CO 2 emission reduction are 8.21t and 23.09t, respectively. Changchun exhibits relatively poor overall performance. Therefore, the integrated power generation system can flexibly select operating strategies according to actual weather conditions, which helps to improve the overall system efficiency, widen the unit operation range and increase the capacity for renewable energy consumption.