Exergy Analysis of 144 Mw Combined Cycle Power Plant Kotri Pakistan

Abstract

The conventional energy analysis evaluates the performance of a thermodynamic system generally on its quantity only. It gives no information about the effect of irreversibilities on performance that occurs inherently during any thermodynamic process. On the other hand, exergy analysis, based on the second law of thermodynamics recognizes magnitudes and locations of the losses due to these irreversibilities. Therefore, the application of exergy analysis for thermodynamic evaluation of conventional power plants is steadily growing. This paper deals with the exergy analysis performed on a 144 MW combined cycle power plant situated at Kotri, Pakistan. The exergy destruction models are used to assess the losses occurred in the key components of the power plant. The results indicate that the total exergy destruction of the power plant is around 288.5 MW; combustion chambers contribute a major share of 168 MW (58.2%) followed by heat recovery steam generators (HRSGs) with 43 MW (14.8%). The energy efficiency and exergy efficiency of the power plant are calculated as 34.41 and 33.40% respectively. Finally, some suggestions regarding the efficiency improvement of the power plant components are given