Combined Energy-Exergy-Control (CEEC) analysis and multi-objective optimization of parabolic trough solar collector powered steam power plant

Abstract eThe achievement of a renewable plant with maximum efficiency (energy and exergy) and a suitable control system (with minimum settling time) is one of the most critical issues in the design and optimization of power plants. Accordingly, in this research, a novel method: Combined Energy-Exergy-Control (CEEC) method is used for the analysis and a new steam power generation system that supplies all the required heat by a set of parabolic trough collectors is used as a case study. A wide range of researches regarding the power cycles separately studied the problem of efficiency improvement without control considerations or an efficient control system without performance considerations. Therefore, in this paper, the problem of achieving an efficient thermodynamic system with appropriate control characteristics was considered using the CEEC method. To this end, the energy and exergy analysis was performed for the proposed cycle, followed by accurately modeling the parabolic trough collectors (PTCs). Then, the governing control equations are presented, and the response time of the control system is determined accordingly. Finally, CEEC optimum configuration is proposed using multi-objective optimization to maximize the energy/exergy efficiency and minimizing the settling time of the proposed cycle. The two-objective optimization outcomes indicated 36.06 and 25.09% improvement in whole cycle energy performance and settling time, and the three-objective optimization (energy-exergy-settling time) stands for 34.02, 28.25 and 17.63% enhancement in target function respectively.