Performance evaluation of a geothermal-driven ejector power-cooling system: A comparative study of different refrigerants

Öz

The growing need for sustainable energy systems has increased research interest in energy systems capable of providing power and cooling from renewable energy resources. In this regard, a geothermal-assisted ejector refrigeration cycle (PERC) is developed and thermodynamically analyzed using five different working fluids, namely R134a, R1234yf, R600a, R1234ze(E), and R717. The performance characteristics are studied by conducting both energy analysis and exergy analysis on Engineering Equation Solver (EES). The impacts of various types of working fluids and geothermal source temperatures on net power production, cooling capacity, energetic efficiency, exergetic efficiency, and exergy irreversibility are carefully assessed in detail. Under the base operating condition of this novel power cycle, R600a produces the maximum net power output and exergy efficiency of 324.5 kW and 32.98%, respectively, while exhibiting the minimum exergy destruction of 660.8 kW. In contrast, R717 offers the maximum cooling capacity and energy efficiency of 344.7 kW and 22.81%, respectively. It can be observed from the parametric study that increasing the geothermal source temperature from 160 °C to 200 °C increases both the power and cooling output for all the working fluids. Higher source temperatures cause higher exergy destruction and lower exergy efficiencies because of greater irreversibilities within the system. It is thus concluded that the choice of working fluid plays an important role in determining the thermodynamic performance of the system. R600a has shown the highest exergy efficiency, while R717 has emerged as a better choice for cooling applications.

Anahtar Kelimeler

• Geothermal energy
• Ejector power-cooling system
• Energy and exergy analysis
• Thermodynamic Performance
• Refrigerants

Kaynakça

1. [1] Mason JE. World energy analysis: H2 now or later? Energy Policy 2007; 35: 1315-1329.
2. [2] Aizura AB, Mahlia TMI, Masjuki HH. Potential fuel savings and emissions reduction from fuel economy standards implementation for motor-vehicles. Clean Technologies and Environmental Policy 2010; 12: 255-263.
3. [3] Li Y, Pu Y. The impact of renewable energy products trade on carbon emissions spatial correlation: Based on a complex network approach. Renewable Energy 2026: 126012.
4. [4] Ebadollahi M, Shahbazi B, Ghaebi H. Efficiency and flexibility enhancement of nanofluid-based hybrid solar desalination system equipped with thermoelectric generator for eco-friendly freshwater and power cogeneration. Process Safety and Environmental Protection 2024; 190: 108-122.
5. [5] Wang K, Xue Y, Guo Q, Shahidehpour M, Zhou Q, Wang B, et al. A coordinated reconfiguration strategy for multi-stage resilience enhancement in integrated power distribution and heating networks. IEEE Transactions on Smart Grid 2023; 14: 2709-2722.
6. [6] Garkoti P, Ni JQ, Thengane SK. Energy management for maintaining anaerobic digestion temperature in biogas plants. Renewable and Sustainable Energy Reviews 2024; 199: 114430.
7. [7] Alirahmi SM, Assareh E, Pourghassab NN, Delpisheh M, Barelli L, Baldinelli A. Green hydrogen & electricity production via geothermal-driven multi-generation system: Thermodynamic modeling and optimization. Fuel 2022; 308: 122049.
8. [8] Xing L, Li J. Proposal of biomass/geothermal hybrid driven poly-generation plant centering cooling, heating, power, and hydrogen production with CO2 capturing: Design and 3E evaluation. Fuel 2022; 330: 125593.

9. [9] Alexis GK. Performance parameters for the design of a combined refrigeration and electrical power cogeneration system. International Journal of Refrigeration 2007; 30: 1097-1103.
10. [10] Besagni G, Mereu R, Inzoli F. Ejector refrigeration: A comprehensive review. Renewable and Sustainable Energy Reviews 2016; 53: 373-407.
11. [11] Saleh B. Performance analysis and working fluid selection for ejector refrigeration cycle. Applied Thermal Engineering 2016; 107: 114-124.
12. [12] Dahmani A, Aidoun Z, Galanis N. Optimum design of ejector refrigeration systems with environmentally benign fluids. International Journal of Thermal Sciences 2011; 50: 1562-1572.
13. [13] Selvaraju A, Mani A. Analysis of an ejector with environment friendly refrigerants. Applied Thermal Engineering 2004; 24: 827-838.
14. [14] Chen J, Zhu K, Huang Y, Chen Y, Luo X. Evaluation of the ejector refrigeration system with environmentally friendly working fluids from energy, conventional exergy and advanced exergy perspectives. Energy Conversion and Management 2017; 148: 1208-1224.
15. [15] Gil B, Kasperski J. Efficiency analysis of alternative refrigerants for ejector cooling cycles. Energy Conversion and Management 2015; 94: 12-18.
16. [16] Sun DW. Comparative study of the performance of an ejector refrigeration cycle operating with various refrigerants. Energy Conversion and Management 1999; 40: 873-884.
17. [17] Xie Y, Zheng X. Techno-economic optimization of a geothermal multi-product layout composed of a CO2 trans-critical Rankine-LNG system integrated with ejector cooling system and HDH desalination unit. Desalination 2025; 593: 118180.
18. [18] Ebadollahi M, Yousefi P, Yu H. Inherently safety design of an advanced geothermal-driven triple cooling system: 4E and safety-based optimization framework. Thermal Science and Engineering Progress 2025; 67: 104117.
19. [19] Afzal S, M. Ziapour B. Transient analysis and thermal design of a solar-powered cooling system for an office building: Enhancements using phase change materials and zeotropic mixtures in ejector refrigeration cycle. Energy 2024; 309: 133126.
20. [20] Bao J, Lin Y, He G. Working fluids comparison and thermodynamic analysis of a transcritical power and ejector refrigeration cycle (TPERC). International Journal of Refrigeration 2017; 82: 262-272.
21. [21] Naghibi Fard SA, Deymi-Dashtebayaz M, Ghorbani S. Thermoeconomic optimization of combined cooling, heating, and power (CCHP) systems for building energy efficiency using compression and ejector refrigeration cycles. Journal of Building Engineering 2025; 103: 112093.
22. [22] Zhang J, Zhang Z, Zhou S, Hui H, Mei N, Yuan H. Performance enhancement of the combined power-refrigeration cycle using a liquid-gas-gas ejector for ocean thermal energy conversion. Energy Conversion and Management 2023; 296: 117688.
23. [23] Li Y, Basem A, Abed Balla HH, Alkhatib OJ, Khlifi MA, Makhmudov S, et al. Machine learning-optimized geothermal multi-generation with DFOFC/ERC/RO/DHU for cooling/heating from low-to-medium temperature heat sources. International Communications in Heat and Mass Transfer 2026; 177: 111433.
24. [24] Yang X, Zheng N, Zhao L, Deng S, Li H, Yu Z. Analysis of a novel combined power and ejector-refrigeration cycle. Energy Conversion and Management 2016; 108: 266-274.
25. [25] Habibzadeh A, Rashidi MM, Galanis N. Analysis of a combined power and ejector-refrigeration cycle using low temperature heat. Energy Conversion and Management 2013; 65: 381-391.
26. [26] Moran MJ, Shapiro HN, Boettner DD, Bailey MB. Fundamentals of engineering thermodynamics. John Wiley & Sons, 2010.
27. [27] Wang J, Dai Y, Sun Z. A theoretical study on a novel combined power and ejector refrigeration cycle. International Journal of Refrigeration 2009; 32: 1186-1194.
28. [28] Landoulsi H, Elakhdar M, Nehdi E, Kairouani L. Performance analysis of a combined system for cold and power. International Journal of Refrigeration 2015; 60: 297-308.