Techno-economic, environmental and emergy analysis and optimization of integrated solar parabolic trough collector and multi effect distillation systems with a combined cycle power plant

Highlights: • A novel thermal system including a solar collector and a desalination is proposed. • Thermoflex software is used to simulate the system based on thermodynamic concepts. • Simulation is conducted based on six different thermodynamic and economic indicators. • Artificial neural networks/genetic programming are used to reduce optimization time. • The multi-criteria optimization is applied to find system's optimal conditions. In this investigation, the improvement of the combined power plant that is located in Qom province was studied based on using solar energy and multi-effect desalination system. In this regard, energy, exergy, exergoeconomic, exergoenvironmental, emergoeconomic, emergoenvironmental as (6 E) analysis has been performed. Also, multi -objective genetic algorithm (MOGA) was applied to optimization of the propose cycle in view of 6 E analysis. Due to the high complexity of the optimization problem and reduce the computation time, the combination of genetic programing and artificial neural network has been employed to generate exact correlation for objective functions. The initial results demonstrated that adding the solar-based-thermal system caused an improvement of about 1.91% in the exergetic efficiency of the base plant. Moreover, by simultaneous integration of solar unit and desalination system in the base plant, the new-designed plant could generate 33 kg/s freshwater. It was determined from optimization results that the exergetic efficiency of the proposed plant increased by 3.22%. Furthermore, after optimization and at the optimum operating condition, power generation costs, power generation's environmental impacts, freshwater generation's costs, freshwater production's environmental impacts, and the emergy of the proposed system decreased about 6.27%, 24.51%, 36.51%, 26.13%, and 1.87%, respectively.