Energy and Exergy Analysis of a 348.5 MW Steam Power Plant

Abstract

In the present work, the energy and exergy analysis of Kostolac power plant in Serbia is presented. The primary objectives of this article are to analyze the system components separately and to identify and quantify the sites having the largest energy and exergy losses. The energy and exergy efficiency is calculated using the plant operating data from the plant at different loads. The load variation is studied with the data at 100% and 60% of full load. Moreover, the effects of the load variations are calculated in order to obtain a good insight into this analysis. The performance of the plant is estimated by a component-wise modeling, and a detailed break-up of energy and exergy losses for the considered plant has been presented. The results show that energy losses have mainly occurred in the condenser where 421 MW is lost to the environment while only 105.78 MW has been lost from the boiler. Nevertheless, the irreversibility rate of the boiler is higher than the irreversibility rates of the other components. The percentage ratio of the exergy destruction to the total exergy destruction was found to be maximum in the boiler system (88.2%) followed by the turbines (9.5%), and then the forced draft fan condenser (0.5%). In addition, the calculated thermal efficiency based on the lower heating value of fuel was 39% while the exergy efficiency of the power cycle was 35.77%.