Degradation Effects on Combined Cycle Power Plant Performance—Part II: Steam Turbine Cycle Component Degradation Effects

Abstract

This is the second paper exploring the effects of the degradation of different components on combined cycle gas turbine (CCGT) plant performance. This paper investigates the effects of degraded steam path components of steam turbine (bottoming) cycle have on CCGT power plant performance. Areas looked at were, steam turbine fouling, steam turbine erosion, heat recovery steam generator degradation (scaling and/or ashes deposition), and condenser degradation. The effect of gas turbine back-pressure on plant performance due to HRSG degradation is also discussed. A general simulation FORTRAN code was developed for the purpose of this study. This program can calculate the CCGT plant design point performance, off-design plant performance, and plant deterioration performance. The results obtained are presented in a graphical form and discussed.