Multi-objective optimization of gas turbine combined cycle system considering environmental damage cost of pollution emissions

Abstract

Currently, most of the performance analysis and optimization design of the gas turbine combined cycle (GTCC) units ignore the economic loss to the environment caused by the pollutant emissions. In this paper, based on the structure theory of thermoeconomics, an environmental thermoeconomic cost model is established. And then an annual total cost model is established, which can reflect the real economic performance. Based on the comprehensive analysis of the energy, economy and environment, with the objectives of the higher exergy efficiency, less annual total cost and lower specific CO2 emission rate, a multi-objective optimization study of the GTCC unit is conducted using the genetic algorithm (GA) in this paper. Pareto frontiers for the multi-objective optimization has been obtained with GA, and in turn a design plan can be selected from the Pareto frontier according to the preference. The multi-objective optimization results show that the optimized system can greatly increase the system environmental thermoeconomic performance. Moreover, the effects of main variables on the economic performance index of the optimized system are investigated. The results show that the natural gas price has the greater impact on the economic performance index compared with the pollutants environmental damage cost and the non-energy cost.