Advanced Exergoeconomics Analysis of Gas-Steam Combined Cycle Power Generation System

Abstract

ObjectivesThe advanced exergoeconomics analysis method based on exergetic analysis development can refine the economic costs of splitting system components and deeply explore the underlying reasons for the formation of economic costs.MethodsCombining advanced exergetic analysis, advanced exergoeconomics analysis method is used to split the costs of the components in the gas-steam combined cycle power generation system into endogenous, exogenous, avoidable and unavoidable costs, and calculate them.ResultsUnder the design conditions, the avoidable loss in the combustion chamber in the combined cycle power system is the largest, which is 28.41 MW, accounting for 26.55% of the combustion chamber loss. Based on the results of the analysis, different improvement measures are proposed for the turbine to reduce the endogenous and exogenous losses of the system. The largest share of the annualized cost of the system is the endogenous avoidable portion, and the bottom-cycle improvement is prioritized highest for the high-pressure cylinder, followed by the low-pressure cylinder. The exogenous share of annualized costs in the combined cycle power system is 80.59%, of which the exogenous avoidable portion is 40.04%.ConclusionsThe findings of the study can provide the system with a multifaceted energy efficiency evaluation perspective and an improvement direction to optimize the cost.

Keywords

• power generation system
• gas-steam combined cycle
• advanced exergoeconomics analysis
• economic cost
• advanced exergy analysis