Analysis of cycle configurations for the modernization of combined heat and power plant by fitting a gas turbine system

The application of a gas turbine generally allows to increase the number of possible configurations of cogenerated heat and electrical power systems, which became a significant substiture for classic, coal-fired power plants. They are characterized by better thermodynamical, economical, ecological, and operating indexes. Gas turbine units are also the best option for the modernization of existing power plants. This paper discusses the effectiveness of various technological configurations with gas turbines, which are to be applied during modernization projects of already existing conventional combined heat of the entropy method allow to determine entropy generation in each section of a combined heat and power (CHP) plant. Several criteria were taken into consideration while analyzing the effectiveness, the efficiency of the HRSG and the steam cycle, the efficiency of the whole thermal electric power station, the exergetic efficiency of the HRSG and the steam cycle, and the fuel efficiency, index. It was assumed that gas turbines operate under their nominal conditions. The composite curves were also taken into consideration while choosing the type of the turbine. The modernization projects tends not to eliminate those existing power plant sections (machines and equipment), which are able to operate further. The project suggests that those units should remain in the system, which satisfy the applied durability criterion. The last phase of the optimization project focuses on the sensibility verification of several steam-gas CHP plant parameters and their influence on the whole system. [DOI: 10-1115/1.1765126]