Fuel Utilization Factor Research Articles

Experimental study of homogeneous charge compression ignition engine operation fuelled by emulated solid oxide fuel cell anode off-gas

A solid oxide fuel cell (SOFC) hybrid system is a system that combines an SOFC with an additional power generation device to increase the efficiency of the system. The SOFC–gas turbine hybrid system has been primarily investigated for SOFC hybrid systems. However, the current power generation capacity of an SOFC is less than several MWs; for this generation capacity, an internal combustion engine is generally more efficient and economical than a gas turbine. Focusing on this point, recently, the concept of an SOFC–internal combustion engine hybrid system was proposed. However, the operation of this system has not been experimentally studied yet. In this paper, as the first step in an experimental investigation of the hybrid system, an experimental study on the operation of an internal combustion engine fuelled by SOFC anode off-gas was conducted. To successfully combust the SOFC anode off-gas, which includes a large amount of diluents (H2O and CO2), the homogeneous charge compression ignition (HCCI) method was selected instead of spark ignition as the combustion strategy of the internal combustion engine in the hybrid system. For the HCCI engine experiments, a single-cylinder HCCI engine and experimental equipment for emulating SOFC anode off-gas were constructed. Various HCCI engine experiments were performed while varying several system control parameters, e.g., the fuel utilization factor of an SOFC, which primarily affects the composition and flow rate of the engine intake gas. The experiments indicated that, in general system operating condition, HCCI engine operation yields a significant amount of power (w/25–30% gross indicated efficiency) and produces significantly low NOx emissions (<5 ppm @ O2 15%) under stable HCCI combustion (<5% COV IMEPg, which is the coefficient of variance of the gross indicated mean effective pressure). Considering that the experiment was performed using a small single-cylinder engine, these experimental results reveal that the use of an HCCI engine as the bottoming cycle in an SOFC hybrid system is promising. In addition, it has been found how each system control parameter affects HCCI engine operation. It was confirmed that HCCI engine operation was not always stable in all system operating conditions. System operating conditions that induce an exceedingly low engine load (<1.8 bar IMEPg, which is the gross indicated mean effective pressure) should be avoided as it decreases the stability of engine operation. Additionally, system operating conditions that make an engine intake gas with excessive dilution (fuel molar fraction < 0.125) should be avoided to decrease the amount of unburned CO emission and maintain a CO combustion efficiency higher than 90%.

تحلیل پارامتریک و بهینهسازی سیستم جدید تولید سهگانه بر پایه پیل سوختی اکسید جامد لولهای

In this article, a new power, cooling and heating trigeneration system consisting of solid oxide fuel cell - gas turbine, a heat recovery steam generator, generator-absorber[1]heat exchange absorption refrigeration cycle and a heat exchanger for heat recovery has been studied from a parametric and optimization perspective. In the present research, in order to control the wasted heat, HRSG is located upstream of GAX, and then, the wasted heat at the system output is used at HR. Due to the important role of the fuel cell in the introduced system, the electrochemical analysis is complete for the fuel cell. Then, the influences of current density, fuel utilization factor, compressor pressure ratio and air utilization factor on the performance of the system are investigated. The optimization of the system is performed in the method of the genetic algorithm to determine the optimal functional points. After optimization and exergoeconomic analysis, the the minimum sum of the unit costs of products, the exergy destruction cost rate and exergoeconomic factor for the overall system is equal to 277.2$/GJ, 40.8$/h and 27.8%, respectively. Therefore, increase in the components’ capital costs can improve the exergoeconomic performance of the system.

Parametric analysis of the exergoeconomic variables of a solid oxide fuel cell (SOFC) coupled with a vapour-adsorption refrigeration system (VARS)

This paper aims at performing a parametric analysis of the thermoeconomics costs associated with an integrated solid oxide fuel cell (SOFC) system with a vapour-adsorption refrigeration (VAR) system. Particular emphasis is put on the cost of the SOFC’s product (i.e. the electrical energy) and on the cost of the VAR’s product (i.e. the cooling effect). In order to do so, an hybrid system simulator was constructed to determine the influence of SOFC operating parameters: current density, inlet flow temperature, fuel utilization factor and steam to carbon ratio, on the exergy-based costs of the products as well as on the exergoeconomic factors. Results of the analysis show that an energy-based costing can lead to overvaluing the cost of an energy asset. Furthermore, the minimum exergy-based unit cost of electricity is 14 $/GJ and of cooling is 16 $/GJ. The exergoeconomic factor of the VAR systems is the most affected by the operating variables. From this study, it is concluded that production of cold is not highly cost-effective under the operating conditions studied herein.

Comparative study of combined solid oxide fuel cell-gas turbine-Organic Rankine cycle for different working fluid in bottoming cycle

Worldwide efforts are being made for evolving viable electricity generation alternative to the traditional fossil fuel based power generation systems and also to enhance the efficiency of existing power generation systems. Studies have been made for integrating fuel cell with gas turbine cycle and Organic Rankine cycle, but there exist possibility of further investigation by incorporating the measures to increase effective energy utilization in the cycle along with consideration of different working fluids in Organic Rankine cycle. In the present paper, a combined cycle system consisting of technologies namely solid oxide fuel cell, gas turbine and Organic Rankine cycle is studied. The considered combined cycle system employs Heat Recovery Steam Generator followed by Organic Rankine cycle as bottoming cycle for recovering the waste heat coming out from hybrid SOFC-GT system through a Heat Recovery Vapour Generator. The considered SOFC-GT system has methane gas being used as fuel which is reformed by both external and internal reformers with anode gas recycling. Here three different working fluids namely R141b, R245fa and R236fa are used in bottoming Organic Rankine cycle for comparing their effects on the cycle performance of proposed SOFC-GT-ORC combined cycle system based on first law of the thermodynamics. Results have been obtained from the computer simulation based on thermodynamic modeling of SOFC-GT-ORC combined cycle and the effects of gas turbine inlet temperature, cycle pressure ratio, fuel utilization factor and ORC turbine inlet temperature are investigated on the cycle performance. The study indicates that the efficiency is increased about 8%-12% by recovering SOFC-GT waste heat through ORC and R236fa is found to be the best in terms of power generation capacity and efficiency of SOFC-GT-ORC system. Outcome from this paper gives insight to the power sector professionals and research community working for evolving efficient and robust power generation alternatives based on the combination of direct energy conversion system and indirect energy conversion system.

Optimal Load-Tracking Operation of Grid-Connected Solid Oxide Fuel Cells through Set Point Scheduling and Combined L1-MPC Control

An optimal load-tracking operation strategy for a grid-connected tubular solid oxide fuel cell (SOFC) is studied based on the steady-state analysis of the system thermodynamics and electrochemistry. Control of the SOFC is achieved by a two-level hierarchical control system. In the upper level, optimal setpoints of output voltage and the current corresponding to unit load demand is obtained through a nonlinear optimization by minimizing the SOFC’s internal power waste. In the lower level, a combined L1-MPC control strategy is designed to achieve fast set point tracking under system nonlinearities, while maintaining a constant fuel utilization factor. To prevent fuel starvation during the transient state resulting from the output power surging, a fuel flow constraint is imposed on the MPC with direct electron balance calculation. The proposed control schemes are testified on the grid-connected SOFC model.

Electrical and thermal analysis of an intermediate temperature IIR‐SOFC system fed by biogas

AbstractAn Intermediate Temperature Solid Oxide Fuel Cells (IT‐SOFC) system fed by not conventional fuels such as biogas can produce electric energy with high conversion efficiency and thermal energy. Inside the energy system, the methane in the biogas is mixed with steam, and then it is converted into carbon monoxide, hydrogen and carbon dioxide through steam reforming and water gas shift chemical reactions in an indirect internal reformer (IIR) mostly and in the SOFC anode minimally. The chemical energy of the electro‐oxidation of hydrogen and carbon monoxide produced is directly converted into electric energy in the fuel cell anode. A part of the anode exhaust gas can be recirculated at the IIR inlet and the percentage of this recirculated anode exhaust gas together to the fuel utilization factor influence the performances (electric and thermal powers and efficiencies, primary energy saving and first law efficiency) of the SOFC system in a cogenerative arrangement. Through the simulation model of an IT‐SOFC system fed by biogas in cogenerative arrangement, which was formulated ad hoc and implemented in a Matlab environment, the influence of the above‐mentioned variables on the IT‐SOFC system performances was evaluated. The verification of carbon formation at the anode was made.

Exergoenvironmental comparison of internal reforming against external reforming in a cogeneration system based on solid oxide fuel cell using an evolutionary algorithm

Two different arrangements of a system including a cogeneration plant based on solid oxide fuel cell with internal reforming (IR-SOFC) and solid oxide fuel cell with external reforming (ER-SOFC) for producing power and hot water are modeled and analyzed thermodynamically. Also, in order to determine the optimal values of design parameters including SOFC inlet temperature, current density, steam-to-carbon ratio, and fuel utilization factor, an evolutionary algorithm for multi-objective optimization purposesis applied. For both systems, two objective functions including the exergy efficiency and CO2 gas emission (EMI) in kg/MWh, with the aim of maximizing the exergy efficiency and minimizing the EMI are considered. The optimization results revealed that at the final optimal design point, the value of the exergy efficiency of the cogeneration system based on IR-SOFC is about 9.6% more than that of the system based on ER-SOFC. Moreover, the amount of EMI in the first configuration (cogeneration system based on IR-SOFC) is about 1.4% lower than that of the second one (cogeneration system based on ER-SOFC).

Design and analysis of a waste gasification energy system with solid oxide fuel cells and absorption chillers

Energy saving is an open point in most European countries where energy policies are oriented to reduce the use of fossil fuels, greenhouses emissions and energy independence, and to increase the use of renewable energies. In the last several years, new technologies have been developed and some of them received subsidies to increase installation and reduce cost. This article presents a new sustainable trigeneration system (power, heat and cool) based on a solid oxide fuel cell (SOFC) system integrated with an absorption chiller for special applications such as hotels, resorts, hospitals, etc. with a focus on plant design and performance. The proposal system is based on the idea of gasifying the municipal waste, producing syngas serving as fuel for the trigeneration system. Such advanced system when improved is thus self-sustainable without dependency on net grid, district heating and district cooling. Other advantage of such waste to energy system is waste management, less disposal to sanitary landfills, saving large municipal fields for other human activity and considerable less environmental impact. Although plant electrical efficiency of such system is not significant but fuel utilization factor along with free fuel, significant less pollutant emissions and self-sustainability are importance points of the proposed system. It is shown that the energy efficiency of such small tri-generation system is more than 83% with net power of 170 kW and district energy of about 250 kW.

Process integration of coal fueled chemical looping hydrogen generation with SOFC for power production and CO2 capture

Chemical looping hydrogen generation (CLHG) is integrated with solid oxide fuel cell (SOFC) and combined cycle for high-efficiency power production with CO2 sequestration. To avoid energy penalty imposed by cryogenic air separation unit for oxygen production, the CLHG is directly fed by coal. The coal gasification and iron oxide reaction occur in the same reactor and no gaseous oxygen is used in gasification. The CLHG operates at an auto-thermal condition by solid circulation. The proposed system could achieve a net power efficiency of 41.59% at a baseline case. Sensitivity analysis is conducted as well on the basis of heat balance. Varying the temperatures of CLHG reactors and iron oxide circulation rate influences the system's efficiency. The increase of the fuel cell's temperature and fuel utilization factor favors the system's net power efficiency. In addition to high net power efficiency, the CO2 capture rate of the proposed system is up to ∼100%, resulting in a virtual carbon-free power plant.

Solid oxide fuel cell short stack performance testing - Part A: Experimental analysis and μ-combined heat and power unit comparison

The need to experimentally understand the detailed performance of SOFC stacks under operating conditions typical of commercial SOFC systems has prompted this two-part study. The steady state performance of a 6-cell short stack of yttria (Y2O3) stabilised zirconia (YSZ) with Ni/YSZ anodes and composite Sr-doped lanthanum manganite (LaMnO3, LSM)/YSZ cathodes is experimentally evaluated. In Part A, the stack characterisation is carried out by means of sensitivity analyses on the fuel utilisation factor and the steam-to-carbon ratio. Electrical and environmental performances are assessed and the results are compared with a commercial full-scale micro-CHP system, which comprises the same cells.The results show that the measured temperature dynamics of the short stack in a test stand environment are on the order of many minutes; therefore, one cannot neglect temperature dynamics for a precise measurement of the steady state polarisation behaviour. The overall polarisation performance is comparable to that of the full stack employed in the micro-CHP system, confirming the good representation that short-stack analyses can give of the entire SOFC module. The environmental performance is measured verifying the negligible values of NO emissions (<10 ppb) across the whole polarisation curve.

Design of SOFC based oxyfuel combustion systems with anode recycling and steam recycling options

A solid oxide fuel cell (SOFC) based power plant incorporating an oxyfuel combustion process to reduce carbon dioxide emissions is analyzed. The effects of key parameters, such as the steam-to-carbon ratio, fuel utilization factor, and temperature, on the current density, voltage, heat production, and requirements of each unit are investigated. In addition, the overall performance of the SOFC–oxyfuel integrated systems with anode recycling and steam recycling are studied and compared. The SOFC system with anode recycling provides better electrical efficiency than that with steam recycling because of the high utilization of fuel in the SOFC and the ability to integrate a fuel turbine. In the SOFC with steam recycling, a fuel turbine cannot be implemented because there is insufficient heat for preheating the inlet streams, which is primarily used to vaporize the recycling stream. The conditions for SOFC–oxyfuel combustion in systems with anode or steam recycling that provide the optimum electrical efficiency are also analyzed.

Modeling of Methanol-Fueled SOFC with Anode Offgas Recycling for Simplified System Design

Objective :Methanol is a fuel that can be synthesized from either fossil fuel or biomass. Use of methanol as a fuel in SOFCs offers several advantages. A major advantage lies in its ease of storage, handling, distribution, and input, being found in liquid form under ambient conditions. Compared to most other fuels, methanol is rather easily produced, and is known to have a lesser tendency for carbon deposition when vaporized and heated at high temperature.In this work, we conducted modeling and simulations of a methanol-fed SOFC system with anode gas recycling. Anode gas recycling provides water vapor in the fuel inlet, thus decreasing the tendency of the feed gas to form carbon deposits in the fuel cell stacks. This strategy also helps reduce thermal stresses in the stacks that would arise if the reforming was attempted in-situ with 100% water vapor originating from outside the SOFC system. The recycling also helps increase the fuel utilization. A thermodynamic analysis was conducted to calculate the energy generated, absorbed, or exchanged in the various blocks of the system, the expected system energy output, as well as conditions under which carbon deposition is prevented. Results:The model is based on an integrated energy process with anode gas recycling, a rated output electrical power of 100 kW, and an electrical efficiency of 50% to initiate simulations. Using the CHEMCAD software, equilibrium gaseous compositions were calculated. The oxygen flow rate and the cell temperature were set at five times the stoichiometric value and 800°C, respectively. Thermodynamic calculations show that the gas mixture at the anode inlet will not lead to carbon deposition above 575°C. The energy generated in the cell by electrooxidation is calculated at 144.6 kW. 44.6 kW of thermal energy is thus generated at the stack level. This heat is removed by the anode and cathode outlet flows, as well as minor heat losses through the system walls. A mass recycle ratio of 1.47 was obtained. Energy involved in each of 9 system blocks was calculated. Overall system and electrical efficiencies of 75% and 57% were obtained from simulations based on lower heating value. A voltage ranging from 0.91 to 0.94 V across the cell stacks was obtained at a fuel utilization factor of 80% and a temperature of 800°C. Finally, simulation iterations lead to an output fuel cell power of 98.8 kW, which is close to the power value used as input at the start of simulations.Conclusion:The recycle ratio of 1.47 contributes to system efficiency. By contrast, it was reported that for propane, a fuel utilized in Northern Canada, a recycle ratio greater than 5 is required for reliable functioning of SOFC systems. Modeling and simulation results clearly showed that methanol has very little tendency to form carbon deposits during cracking in situ when used in a simple anode gas recycling system. A very good electrical efficiency is thus obtained.

CFD Modeling of SOFC Cogeneration System for Building Application

Abstract This paper focuses on CFD modeling of Solid oxide fuel cell (SOFC) which is coupled with co-generation system. The SOFC cogeneration system is a low emission and energy efficient combined heat and power (CHP) is a most promising candidate in the field of electric and thermal energy generation technology for execution in future commercial buildings. Using finite volume approach CFD modeling of SOFC has been carried out by using commercial software COMSOL 4.3.1. The performance characteristic of an SOFC has been examined by performing parametric analysis. The effect of fuel utilization factor, recirculation ratio, operating temperature significantly affects the cell performance. It has been observed that, internal reforming is advantageous over the external reforming system in terms of thermo-economics and power supply.

Improving fuel utilization in SmAHTR with spectral shift control design: Proof of concept

This paper presents a spectral shift design based approach to improve the fuel utilization factor or alternatively to increase the cycle length in a graphite moderated reactor. The feasibility of this concept was tested in the Small Advanced High-Temperature Reactor (SmAHTR). This is a small sized Fluoride-salt-cooled high-temperature reactor (FHR) that uses tri-isotropic (TRISO)-coated particle fuels and graphite moderator materials. A major benefit of the TRISO particles is the ability to mitigate fission product release in the case of an accident. However, the fabrication costs associated with TRISO particles are expected to be significantly higher than the traditional UO2 fuel. The preliminary studies presented in the paper are focused on extending the achievable irradiation period without increasing the value of the enrichment. In order to increase the discharge burnup, the design includes graphite structures that are initially removed from the core. This imposes a harder spectrum, which enhances the breeding of 239Pu. Then, the graphite structures are gradually and continuously inserted into the core to sustain criticality. This procedure shifts the hard spectrum into a more thermal one and enables a more efficient utilization of 239Pu. The preliminary results indicate that this design achieves considerably longer irradiation periods and hence lower fuel cycle costs than the reference design.

Numerical simulations for testing performances of an Indirect Internal CO2 Reforming Solid Oxide Fuel Cell System fed by biogas

The paper presents a wide campaign of numerical simulations carried out subsequently to the formalization and the implementation in Matlab of a steady state-zero-dimensional numerical model. It describes the various processes of a global self sustained Indirect Internal CO2 Reforming Solid Oxide Fuel Cell System fed with biogas. The plant considered includes a thermo-electrochemical section in which the conversion of biogas into a hydrogen-rich stream occurs. It then feeds the electrochemical core where the generation of electrical and thermal energy take place. In addition, a heat exchanger to preheat fresh gases, a combustor to burn fuel traces in the fuel cell discharge gas and a system for partial recirculation of anode output gas are included.The simulations aim at describing the mapping of the system performance and the comprehension of its behaviour at the several operating and feeding conditions to which it can be subjected. Simulations are conducted as a function of the real possible feeding CO2/CH4 ratio for the biogas. Moreover, several simulations according to the fuel utilization factor, oxidant utilization factor, anode exhaust gas recirculation factor and the pressure are effected to equip an analysis kit for performance prediction. A check analysis on carbon formation is also considered to verify safe functioning.

Energy, exergy and sensitivity analyses of a hybrid combined cooling, heating and power (CCHP) plant with molten carbonate fuel cell (MCFC) and Stirling engine

A hybrid combined cooling, heating and power (CCHP) system which consists of molten carbonate fuel cell (MCFC), Stirling engine and double effect LiBr/H2O absorption chiller is introduced and analyzed. Molten carbonate fuel cell is the main power production source which its exhausted heat is used as heat source of the Stirling engine. Exhausted heat from the Stirling engine is used as heat source of the absorption chiller’s generator. The produced power of the process is 6482 kW, also it provides 2137 kW heat duty and 1372 kW cold duty. Performance of the process is evaluated by energy and exergy analysis methods. Also sensitivity of the overall and electrical efficiencies to the fuel utilization factor, air flow rate to the burner, burner outlet temperature and oxidant flow rate are analyzed. Results of the energy analysis show that overall and electrical efficiencies are 71.71% and 42.28% respectively. Exergy analysis shows that molten carbonate fuel cell, Stirling engine and gas turbine have considerable efficiencies. Highest exergy destruction rate is related to the CH4 and H2 burners that mostly is because of the irreversible nature of the combustion.

An innovative system by integrating the gasification unit with the supercritical water unit to produce clean syngas for solid oxide fuel cell (SOFC): System performance assessment

Existence of impurities in the product gas hinders the application of the system which combines gasification with solid oxide fuel cell (SOFC). A new method is proposed to produce qualified syngas, which integrates the gasification unit with the supercritical water unit (SWU). The SWU contains supercritical water mixer, separator, reactor (SWR) and expander. To analyze performance of the proposed process from a systematic perspective, downstream operating units primarily including SOFC, burner, heat recovery steam generation and steam cycle are designed. Model for the whole system is developed by using Aspen Plus and a mathematical model for the SOFC. Sensitivity analysis regarding the fuel utilization factor (Uf) and the mass ratio of tars to supercritical water (T/W) are conducted in terms of system electrical efficiency, SOFC electrical efficiency and cell voltage. Results show that combustible components in the obtained syngas mainly contain CH4, H2, and CO. Tars are completely decomposed and only slight amount of light hydrocarbons (except CH4) are present. One SWR can undertake the functions of water gas shift, tar reforming and methane synthesis concurrently. The integrated process can offer a combustible components efficiency of 78.2%, and the system electrical efficiency is predicted to be 46.3%. Uf has a significant influence on the SOFC electrical efficiency, while it has slight influence on system electrical efficiency. As the T/W rises from 1.6% to 2%, system electrical efficiency, SOFC electrical efficiency and cell voltage slightly increase.

Integration of biomass gasification with a solid oxide fuel cell in a combined cooling, heating and power system: A thermodynamic and environmental analysis

A biomass-fueled combined cooling, heating and power (CCHP) system is proposed and thermodynamically assessed. The system consists of a biomass gasifier (as the primary energy source), a solid oxide fuel cell (as the power generation unit), a double effect absorption refrigeration cycle (for cooling production) and a HRSG (for steam production for heating purposes). Taking into account the environmental considerations, energy and exergy analyses are conducted for the proposed system and its performance is compared with the corresponding power generation unit and the CHP system. Through a parametric study it is observed that the current density and fuel utilization factor play key roles on the system performance. In addition, considering the system as a combination of three subsystems, i.e. the SOFC, CHP system and CCHP system, an environmental impact assessment in terms of CO2 emission is conducted. Municipal solid waste is examined as biomass and it is observed that maximum exergy efficiency of the CCHP system is 37.92% with a CO2 emission of 20.37 t/MWh which shows an increase of 49.88% in exergy efficiency and 64.02% decrease in CO2 emission, compared to the solo SOFC system. It is concluded that the air heat exchanger and the gasifier are two major sources of irreversibility in the system and the exergy loss is considerable compared to after burners' exergy destruction.

A comparison between two methods of generating power, heat and refrigeration via biomass based Solid Oxide Fuel Cell: A thermodynamic and environmental analysis

Utilization of biomass energy is of prevalence focus these days. Using these fuels to run the fuel cells is of primary interest. In this regard, two new trigeneration systems (producing power and heating alongside with cooling) based on solid oxide fuel cell fed by either the syngas or biogas are proposed. The performance of systems is analyzed and compared with each other from the thermodynamic viewpoint. Applying the conservation of mass and energy as well as the exergy for each system component and using the engineering equation solver, the system’s performance are modeled. Through a parametric study, the effects of some key variables such as the current density and the fuel utilization factor in the systems’ performance are investigated. In addition, considering the system as a combination of three subsystems, that is, the power generation system, heat and power generation system and trigeneration system, an environmental impact assessment in terms of Carbon dioxide emission is carried out for both digester based Solid Oxide Fuel Cell and gasifier based one. It is observed that using biogas from digester leads to more exergetic (which is 14.56%) and less energetic efficiency (Which is 14.31%), with a Carbon dioxide emission of 17.87ton/MWh for the tri-generation system. The value of this parameter is 21.32ton/MWh when gasifier is used as the supplier of fuel for solid oxide fuel cell.

Thermodynamic and exergoeconomic assessments of a new solid oxide fuel cell-gas turbine cogeneration system

A new indirect integration of a solid oxide fuel cell, a gas turbine and a domestic water heater is proposed and analyzed in detail. Using a proper working fluid for each subsystem, interacting thermally with one another, the proposed system generates power and hot water simultaneously. Thermodynamic and thermoeconomic principles are used to determine the products costs and the order of significance of system components from the viewpoint of exergy destruction. Parametric studies are carried out to reveal the influence on the system performance of several decisive parameters. The results show that the exergy efficiency is maximized at a compressor pressure ratio of 9.49 and a current density of 1642Am−2. The increase in pressure ratio however, is not in favor of system’s economic performance. In addition, the sum of unit costs of the products is minimized at a current density of 1523Am−2. Moreover, it is shown that an increase in the gas turbine inlet temperature or steam to carbon ratio deteriorates both the thermodynamic and economic performances of the system. Furthermore, the results indicate that a higher fuel utilization factor improves the thermodynamic and economic behavior of the system. Finally, it is revealed that an increase in the gas turbine air flow rate enhances the energy efficiency and worsens the sum of unit costs of the products. The exergy efficiency however, is maximized at a gas turbine air flow rate of 15.94mols−1.