Thermodynamic and thermoeconomic analyses of an organic Rankine cycle adapted gas turbine cycle using S-CO2 ; [Organik Rankine çevrimi entegre edilmiş S-CO2 kullanılan bir gaz türbin çevriminin termodinamik ve termoekonomik analizi]

In this study, a model of an organic Rankine cycle (ORC) adopted gas turbine cycle using supercritical CO2 (S-CO2) as working fluid is performed. Thermodynamic analyses of a system are carried out using Aspen Plus and EES programs. As a result of thermodynamic analyses, electricity production capacity, energy and exergy efficiencies of the proposed system are evaluated as 1530.88 kW, 23.30% and 59.60%, respectively. For the thermoeconomic analysis of the system, specific exergy costing method, SPECO, is applied as widely used one among the second law based methods. Unit exergetic cost of electricity production for 1 kWh is found to be 7.28 ¢ and the total cost of electricity production for 1530.88 kWh is found to be 114.43 $. Annual return from the system of ORC adopted gas turbine cycle using S-CO2which has the total investment cost of 3,033,300 $ is evaluated as 741,146 $ taking into account the difference between the cost of electricity production and the sale price of electricity. As a result of the thermoeconomic analysis, the payback period of the system is found to be 4.09 years. Purpose: To propose a model (an organic Rankine cycle (ORC) adopted gas turbine cycle using supercritical CO2: S-CO2) for an existing solid waste power plant in the frame of the heat recovery (Waste-to-energy). Theory and Methods: Thermodynamic and thermoeconomic analyses were utilized for the proposed model in order to evaluate the energy and exergy efficiencies. Results: The energy and exergy efficiencies of the system were calculated as 23.30 % and 61.60 % respectively. 1 kWh of electricity generated from GT-ORC system is produced to 7.28 ¢. The total electricity production cost of 1530.88 kW-hours was calculated as $ 111.43. Conclusion: The total cost of the developed GT-ORC system is $ 3,033,300. The difference between the cost of electricity generated from the GT-ORC system and the cost of the electricity sales is expected to be $ 741,146 annually for the proposed GT-ORC system. As a result of this profit, the payback period of the system was calculated as 4.09 years.