SECOND LAW ANALYSIS OF 300 MW STEAM POWER PLANT AT DIFFERENT LOADS
rohan shahoo, Jyoti kale, Ashish Paharia
Exergy, Exergetic efficiency, thermal efficiency, thermal power plant
Power generation has become a vital factor for the development of nation. As there are limited resources of fossil fuels it is required to utilize efficiently in thermal systems. in general the power plants performance is analyzed using Energy Balance and first law of Thermodynamic efficiency. Exergy analysis is significant than energy analysis in the thermal systems as it also considers the excellence of energy source. In this study, the energy and exergy analysis of 2x300 MW Butibori power plant in Nagpur Maharashtra, India is presented. The primary objectives of this paper are to analyze the system components individually and to make out and measure the sites having major exergy losses at different load. The exergy analysis of the plant showed that lost energy in the condenser is thermodynamically irrelevant due to its low quality. In terms of exergy destruction, the main loss was found in the turbine where 55.9% and 35.59% of the fuel exergy input to the cycle was destroyed at 75%, and full load respectively. The percent exergy destruction in the condenser was 19.51% and 21.45 % at 75%, and full load respectively, while all heaters and pumps destroyed less than 30%, and 20 % at 75%, and full load respectively. The calculated second law efficiency of the power cycle was found to be 45.5%, and 44.8% at 75%, and full load respectively which is similar to modern power plants. It was found that exergy destruction rate of the turbine is main over all other irreversibilities in the cycle. It counts alone for (42% - 46%) of losses in the plant. This indicates that great opportunities are available for improvement. However, part of this irreversibility cannot be avoided due to physical, technological, and economic constraints. Although the percent exergy destruction and the exergy efficiency of each component in the system changed with reference environment temperature. Percentage exergy destruction and exergy efficiency both are increased with increase in reference temperature.