Thermal-economic analysis of industrial gas turbine cogeneration plant

Abstract

This work describes the refinery gas turbine cogeneration plant, which is applied in the Arab Gulf area. The measurements have been used to calculate a number of important thermodynamic performance parameters for this plant. These parameters include the steam efficiency, electrical efficiency, net heat rate (NHR), power to heat ratio (PHR), and fuel saving rate (FSR). At full load, the steam and electrical efficiencies are 53.3 adn 28%, respectively, the NHR is equal to 1.33, the PHR is equal to 0.525, and FSR is 0.614. When the plant is operated at part load, all values of thermodynamic parameters are decreased except NHR, which increases to 1.514. The break-even analysis method is presented for the economic analysis. By this method, the total annual cost (TAC) and total annual revenue (TAR) are plotted against the operation hours in a year. The point at which the TAR line crosses the TAR line is called the break-even point in hours of operation. In cases where output is constant (at full load) over the time period considered, the break-even point is 2442 h. When the cogeneration plant runs a different loads, the break-even point is 2926 h. The break-even analysis is used to understand the effects of the variations in fixed and variable costs on the break-even point in hours.