Energy and exergy analysis of a coal fired power plant

In this paper, energy and exergy analysis has been conducted on a subcritical coal fired power plant of Wisconsin Power and Light Company, USA to investigate the steam cycle energy and exergy efficiency. The cycle is analyzed by developing a mathematical model using its operating and design parameters. The analysis is performed using EES (Engineering Equation Solver). The energy analysis shows that major share of energy loss occurs in condenser i.e. 72% of total cycle energy loss, whereas, exergy analysis shows that 83.09% total exergy destruction of cycle occurs in boiler.Furthermore, the simulation results are compared with actual with an absolute error of 3.1%. Additionally, the parametric study is performed to examine the effects of various operating parameters such as main steam pressure and temperature, condenser pressure, terminal and drain cooler temperature difference on net power output, energy and exergy efficiency of cycle. The parametric study shows that the plant has maximum energy and exergy efficiencies at steam pressure of 2500psi, condenser pressure of 1.0psi and main steam temperature of 1100 degree F. Furthermore, these parameters do not seem to change energy and exergy efficiencies significantly. (author)