Advanced exergoenvironmental assessment of a natural gas-fired electricity generating facility

This paper presents conventional and advanced exergoenvironmental analyses of an electricity generation facility located in the Eskisehir Industry Estate Zone, Turkey. This facility consists of gas turbine and steam cycles, which generate electrical power of approximately 37 MW and 18 MW, respectively. Exergy efficiency of the system is 0.402 and exergy destruction rate of the system is 78.242 MW. Unit exergy cost of electrical power generated by the system is 25.66 $/GJ and total exergoeconomic factor of the system is 0.279. Conventional exergy analysis method was applied to the system first. Next, exergy environmental impacts of exergy destruction rate within the facility's components were divided into four parts generally, as endogenous, exogenous, avoidable and unavoidable environmental impact of exergy destruction rate. Through this analysis, improvement potential of the environmental impacts of the components and the overall system and the environmental relations between the components were then determined. Finally, exergoenvironmental factor was determined as 0.277 and environmental impact of the electricity was 8.472 (Pts/h). The system has 33% development potential for environmental impacts while its components have weak relations because of big endogenous parts of environmental impacts (80%). It may be concluded that advanced exergoenvironmental analysis indicated that priority should be given to the GT and CC, while defining the improvement strategies.