Technical and Economical Effectiveness of 370 MW Power Unit Repowered by Gas Turbine in Parallel System

Abstract

This chapter presents thermodynamic and economic analysis of electric power unit with the rated capacity of 370 MW operating in a combined-cycle which is repowered by a gas turbine in a parallel system. This analysis takes into consideration the mathematical model of the power unit found in Chap. 3 and Stodola–Flügel turbine passage equations for the steam turbine from Chap. 4, which illustrate the variable concentration of steam stream passing through it as a result of repowering the unit by a gas turbine with a heat recovery steam generator. In the exemplary calculations referred to an assumption is made about the value of gas turbine just as in Chap. 8 and the use of dual pressure heat recovery steam generator. The analysis of the economic efficiency of repowering applies the method presented in Chap. 2.