Performance analysis of a grate stoker coal-fired power plant based on the second law of thermodynamics

In this paper, the performance of a coal-fired plant is assessed using exergy analysis. The plant components were analysed, the exergy destruction of each component was calculated, and the plant overall exergetic efficiency was determined. The boiler and steam turbine were found to have the highest exergy destruction. The percent exergy destruction in the boiler and turbine were 77% and 14.5% of the total exergy destruction; respectively. In addition, the exergy destruction of each component was simulated for different reference state temperatures and for different turbine inlet temperature. It was found that increasing the turbine inlet temperature will increase the efficiency of the power plant cycle up to 42% while the reference state temperature has no significant effect on the main conclusions of the analysis. Thus, implementation of higher temperature and pressure steam boiler will reduce the coal consumption, CO2 emission, and ash generation. The policy implications are also discussed.