In this study, a combined heat and power (CHP) system based on geothermal energy is introduced, analyzed from energy, exergy, economic, and environmental perspectives, and optimized using a genetic algorithm. The system consists of an organic Rankine cycle (ORC) and an improved Brayton cycle, designed to utilize geothermal energy. The energy analysis results show that the system's net power output is 3585 kW, and its heating heat rate is 12278 kW. The energy and exergy efficiencies of the system are calculated to be 42.9% and 47.31%, respectively. The results related to the effects of operational parameters indicate that increasing the maximum pressure in the ORC and the temperature difference across heat exchangers significantly affect energy efficiency, exergy efficiency, and the levelized cost of products. Specifically, for every 100 kPa increase in the ORC’s maximum pressure, the energy efficiency increases by 11.2%, and the exergy efficiency increases by 6.29%. Additionally, an optimization process was carried out using a genetic algorithm to maximize energy and exergy efficiencies and minimize the levelized cost of products. Furthermore, optimization of the proposed system resulted in a 30% reduction in the levelized cost of products and a 9.4% reduction in the exergoenvironmental index.
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Akbari,S A H , Miri,S M and Abolfazli Esfahani,J . (2025). Thermoeconomics Analysis and Optimization of a Geothermal-Based Power and Heat Generation System Using Genetic Algorithm. Science and Technology in Mechanical Engineering, 4(1), 183-201. doi: 10.22034/stme.2025.515220.1118
MLA
Akbari,S A H , , Miri,S M , and Abolfazli Esfahani,J . "Thermoeconomics Analysis and Optimization of a Geothermal-Based Power and Heat Generation System Using Genetic Algorithm", Science and Technology in Mechanical Engineering, 4, 1, 2025, 183-201. doi: 10.22034/stme.2025.515220.1118
HARVARD
Akbari S A H, Miri S M, Abolfazli Esfahani J. (2025). 'Thermoeconomics Analysis and Optimization of a Geothermal-Based Power and Heat Generation System Using Genetic Algorithm', Science and Technology in Mechanical Engineering, 4(1), pp. 183-201. doi: 10.22034/stme.2025.515220.1118
CHICAGO
S A H Akbari, S M Miri and J Abolfazli Esfahani, "Thermoeconomics Analysis and Optimization of a Geothermal-Based Power and Heat Generation System Using Genetic Algorithm," Science and Technology in Mechanical Engineering, 4 1 (2025): 183-201, doi: 10.22034/stme.2025.515220.1118
VANCOUVER
Akbari S A H, Miri S M, Abolfazli Esfahani J. Thermoeconomics Analysis and Optimization of a Geothermal-Based Power and Heat Generation System Using Genetic Algorithm. STME. 2025;4(1):183-201 (In Persian). doi: 10.22034/stme.2025.515220.1118
Science and Technology in Mechanical Engineering