Energy and exergy analysis of Tabriz power plant for different loads

Abstract

The first law of thermodynamics or energy conservation principle is a good tool for thermodynamical processes. By using exergetic analysis of thermodynamical processes which are based on the combination of first and second laws of thermodynamics, we can obtain more information. The main purpose of using exergetic analysis is the better usage of energy resources. This analysis gives better understanding about electric power generation cycles by using availability principle. In this survey, Tabriz power plant with 368, MW capacity has been studied, and then after energetic and exergetic analysis, components which have more losses or less efficiency have been determined in the cycle, and afterward, their need for optimization has been introduced. Then, power plant behavior in load variations has been examined too. The results show that first- and second-law-based efficiencies in nominal load are 40.12% and 37.62%, and upon energetic analysis of cycle, condenser and boiler have the most losses with 420.440 and 192.902, MW, respectively. On the other hand, exergetic analysis shows that boiler, turbine, and condenser have the most exergy destruction with load change from 100% to 50%. In this study, we found that energetic and exergetic efficiencies of cycle had remarkable reductions as the amount of reductions of the first- and second-law-based efficiencies changed from 40.12% and 37.62% to 34.61% and 32.46%, respectively.