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A comprehensive cost correlation analysis was conducted based on available cost correlations, and new equipment cost correlation models were proposed based on QUE$TOR modeling. Cost correlations for various types of equipment such as pumps, compressors, heat exchangers, air coolers, and pressure vessels were generated on the basis of extracted cost data. The models were derived on the basis of robust multivariable regression with the aim of minimizing the residuals by using the genetic algorithm. The proposed compressor models for both centrifugal and reciprocating types showed that the Turton cost estimation for carbon steel compressor and Matche’s and Mhhe’s data were compatible with the generated model. According to the results, the cost trend in the Turton correlation for carbon steel had a somewhat lower estimation than these correlations. Further, the cost trend of the Turton correlation for carbon steel pressure vessels was close to the presented model trend for both bullet and sphere types. The Turton cost trend for U-tube shell-and-tube heat exchangers with carbon steel shell and stainless steel tube was close to the proposed heat exchanger model. Furthermore, the Turton cost trend for the flat-plate heat exchanger using carbon steel was similar to the proposed model with a slight difference.

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In this paper, exergy, exergoeconomic, and exergoenvironmental analysis of a gas turbine cycle and its optimization has been carried out by MOPSO algorithm. Three objective functions, namely, total cost rate, exergy efficiency of cycle, and CO 2 emission rate have been considered. The design variables considered are: compressor pressure ratio, combustion chamber inlet temperature, gas turbine inlet temperature, compressor, and gas turbine isentropic efficiency. The impact of change in gas turbine inlet temperature and compressor pressure ratio on CO 2 emission rate as well as impact of changes in gas turbine inlet temperature on exergy efficiency of the cycle has been investigated in different compressor pressure ratios. The results showed that with increase in compressor pressure ratio and gas turbine inlet temperature, CO 2 emission rate decreases, that is this reduction is carried out with a steeper slope at lower pressure compressor ratio and gas turbine inlet temperature. The results showed that exergy efficiency of the cycle increases with increase in gas turbine inlet temperature and compressor pressure ratio. The sensitivity analysis of fuel cost changes was performed on objective functions. The results showed that at higher exergy efficiencies total cost rate is greater, and sensitivity of fuel cost optimum solutions is greater than Pareto curve with lower total cost rate. Also, the results showed that sensitivity of changes in fuel cost rate per unit of energy on total cost rate is greater than the rate of CO 2 emission.

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This research presents the energy, exergy, economic, and environmental assessment, and multi-objective optimization of a flash-binary geothermal CCHP cycle. A sensitivity analysis of production well inlet temperature and cooling to power flow ratio on exergetic, economic, and environmental parameters was conducted. Furthermore, the effects of the inflation rate and plant working hours on economic parameters were investigated. Results showed that increasing the production well inlet temperature harms exergy efficiency and exergetic performance criteria and results in a gain in exergo-environmental impact index and heating capacity. In addition, the total plant cost increased by raising the production well temperature. Furthermore, increasing the cooling to power flow ratio caused a reduction in exergy efficiency, exergetic performance criteria, and produced net power and an enhancement in exergy destruction, cooling capacity, and total plant cost. The exergy efficiency and total cost rate in the base case were 58% and 0.1764, respectively. Optimization results showed that at the selected optimum point, exergy efficiency was 4.5% higher, and the total cost rate was 10.3% lower than the base case. Levelized cost of energy and the pay-back period at the optimum point was obtained as 6.22 c$/kWh, 3.43 years, which were 5.14% and 6.7% lower than the base case.

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In this paper the exergy, economic and environmental analysis of Aliabad Katoul power plant as well as its multiobjective optimization have been done by NSGA-II algorithm. Two objective functions have been considered. The first objective function is the total cost rate and the second objective function is environmental impact cost. Optimization of objective functions has been done in two modes namely cycle with and without air preheater. The results showed that the existence of air preheater reduces both objective functions. So that in optimum point, for cycle without air preheater, the amount of total cost rate has been about 30% and environmental cost rate was about 33% higher than cycle with air preheater. Also, sensitive analysis of objective functions to fuel unit cost was conducted. At the lower environmental cost rate that the total cost rate was higher, sensitivity of Pareto solutions to the fuel unit cost was more than some parts of figure with smaller total cost rate. Also, exergy losses of various components were obtained that conclusions illustrated that combustion chamber has the maximum rate of exergy destruction (about 73%). Impact of ambient temperature variation on exergy losses and efficiency for different components was studied. The conclusions illustrated that with growing in ambient temperature, exergy efficiency of all parts decreased and exergy losses increased. Also, by rising the ambient temperature, exergy efficiency decreased, so that an increase in temperature from 293 Kelvin to 323 Kelvin, total exergy efficiency decreased from about 51% to 49%.