Sensitivity analysis and exergoeconomic optimization of an improved He-CO2 cascade Brayton cycle for concentrated solar power

Abstract

Nowadays, solar energy is one of the most promising renewable energy sources that can effectively mitigate the current serious energy crisis and environmental pollution. To efficiently utilize solar energy and positively comply with the carbon neutrality policy, this research developed an efficient and environmentally-friendly improved He-CO2 cascade Brayton cycle for concentrated solar power, and then implemented a series of studies, including performance prediction, sensitivity analysis, and exergoeconomic optimization. After optimization, the most suitable condition was determined via a decision-making method, and the exergoeconomic performances of each subsystem and component were thoroughly investigated. Finally, the concentrated solar power system was comprehensively evaluated from the perspectives of thermodynamic and exergoeconomic performance. The numerical results imply that the system provides excellent thermodynamic and exergoeconomic performance with power, investment cost rate, and exergoeconomic factor of 697.75 kW, 33.09 $/h, and 77.48%, respectively, representing an exergy efficiency improvement of 3.51%–6.35% compared to similar concentrated solar power configurations. This research complies with the carbon neutrality policy, meets energy conservation and emission reduction requirements, and offers meaningful guidance for scientists who are committed to improving solar energy conversion and implementing exergoeconomic analysis.