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Optimization of ORC Power Plants for Geothermal Application in Kenya by Combining Exergy and Pinch Point Analysis

Author

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  • Alvin Kiprono Bett

    (Department of Earth Resources Engineering, Graduate School of Engineering, Kyushu University, 744 Motooka, Fukuoka 819-0395, Japan
    Department of Mining, Materials and Petroleum Engineering, Jomo Kenyatta University of Agriculture and Technology, City Square, Nairobi 62000-00200, Kenya)

  • Saeid Jalilinasrabady

    (Department of Earth Resources Engineering, Graduate School of Engineering, Kyushu University, 744 Motooka, Fukuoka 819-0395, Japan)

Abstract

Geothermal energy is a sustainable renewable source of energy. The installed capacity of geothermal energy in Kenya is 847.4 MWe of the total 2.7 GWe. This paper presents the effect of six different working fluids to optimize the geothermal of 21.5 MWe of reinjected brine at a single-flash power plant in Kenya. Engineering Equation Solver (EES) code was used to design and optimize simple organic Rankine (ORC) and regenerative cycles. The objective was to combine pinch point analysis and exergy analysis for the optimum utilization of geothermal energy by varying the turbine inlet pressure, pinch point, and reinjection temperature. The turbine inlet pressures, and pinch points were varied to obtain optimum pressures for higher net power output and exergy efficiencies. As the pressure increased, the efficiencies and net power generated increase to optimal at turbine inlet pressures between 2000 and 3000 kPa. By maintaining a condenser temperature at 46.7 °C, the turbine outlet pressures were 557.5 kPa for isobutene, 627.4 kPa for isobutane, 543.7 kPa for butene, 438.9 kPa for trans-2-butene, 412.3 kPa for R236ea, and 622.9 kPa for R142b. For the pinch point of 10 °C, the working fluid with a lower net power is trans-2-butene at 5936 kW for a flow rate of 138.8 kg/s and the highest reinjection at 89.05 °C. On the other hand, R236ae had a flow rate of 398.2 kg/s, a higher power output of 7273 kW, and the lowest reinjection temperature of 73.47 °C for a 5 °C pinch point. In the pinch point consideration, the suitable fluid will depend on the best reinjection temperatures. The pinch point affects the heat transfer rates and effectiveness in the heat exchangers. The best pinch point is 10 °C, since the reinjection temperatures are the highest between 83 and 89 °C. The analysis showed that for unlimited reinjection temperatures, basic ORC is suitable. The regenerative cycle would be best suited where reinjection temperature is constrained by brine geochemistry.

Suggested Citation

  • Alvin Kiprono Bett & Saeid Jalilinasrabady, 2021. "Optimization of ORC Power Plants for Geothermal Application in Kenya by Combining Exergy and Pinch Point Analysis," Energies, MDPI, vol. 14(20), pages 1-17, October.
    • Handle: RePEc:gam:jeners:v:14:y:2021:i:20:p:6579-:d:654979
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    References listed on IDEAS

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    1. Mohammadzadeh Bina, Saeid & Jalilinasrabady, Saeid & Fujii, Hikari, 2017. "Energy, economic and environmental (3E) aspects of internal heat exchanger for ORC geothermal power plants," Energy, Elsevier, vol. 140(P1), pages 1096-1106.
    2. Florian Heberle & Dieter Brüggemann, 2016. "Thermo-Economic Analysis of Zeotropic Mixtures and Pure Working Fluids in Organic Rankine Cycles for Waste Heat Recovery," Energies, MDPI, vol. 9(4), pages 1-16, March.
    3. Zhao, Yajing & Wang, Jiangfeng, 2016. "Exergoeconomic analysis and optimization of a flash-binary geothermal power system," Applied Energy, Elsevier, vol. 179(C), pages 159-170.
    4. Jalilinasrabady, Saeid & Tanaka, Toshiaki & Itoi, Ryuichi & Goto, Hiroki, 2021. "Numerical simulation and production prediction assessment of Takigami geothermal reservoir," Energy, Elsevier, vol. 236(C).
    5. Rosen, Marc A. & Dincer, Ibrahim & Kanoglu, Mehmet, 2008. "Role of exergy in increasing efficiency and sustainability and reducing environmental impact," Energy Policy, Elsevier, vol. 36(1), pages 128-137, January.
    6. Jesper Graa Andreasen & Martin Ryhl Kærn & Fredrik Haglind, 2019. "Assessment of Methods for Performance Comparison of Pure and Zeotropic Working Fluids for Organic Rankine Cycle Power Systems," Energies, MDPI, vol. 12(9), pages 1-25, May.
    7. Guillermo Valencia Ochoa & Cesar Isaza-Roldan & Jorge Duarte Forero, 2020. "Economic and Exergo-Advance Analysis of a Waste Heat Recovery System Based on Regenerative Organic Rankine Cycle under Organic Fluids with Low Global Warming Potential," Energies, MDPI, vol. 13(6), pages 1-22, March.
    8. Zeyghami, Mehdi, 2015. "Performance analysis and binary working fluid selection of combined flash-binary geothermal cycle," Energy, Elsevier, vol. 88(C), pages 765-774.
    9. Edrisi, Baktosh H. & Michaelides, Efstathios E., 2013. "Effect of the working fluid on the optimum work of binary-flashing geothermal power plants," Energy, Elsevier, vol. 50(C), pages 389-394.
    10. Jalilinasrabady, Saeid & Palsson, Halldor & Saevarsdottir, Gudrun & Itoi, Ryuichi & Valdimarsson, Pall, 2013. "Experimental and CFD simulation of heat efficiency improvement in geothermal spas," Energy, Elsevier, vol. 56(C), pages 124-134.
    11. Astolfi, Marco & Romano, Matteo C. & Bombarda, Paola & Macchi, Ennio, 2014. "Binary ORC (organic Rankine cycles) power plants for the exploitation of medium–low temperature geothermal sources – Part A: Thermodynamic optimization," Energy, Elsevier, vol. 66(C), pages 423-434.
    12. Collings, Peter & Yu, Zhibin & Wang, Enhua, 2016. "A dynamic organic Rankine cycle using a zeotropic mixture as the working fluid with composition tuning to match changing ambient conditions," Applied Energy, Elsevier, vol. 171(C), pages 581-591.
    13. Luo, Chao & Huang, Lichang & Gong, Yulie & Ma, Weibin, 2012. "Thermodynamic comparison of different types of geothermal power plant systems and case studies in China," Renewable Energy, Elsevier, vol. 48(C), pages 155-160.
    14. Astolfi, Marco & Romano, Matteo C. & Bombarda, Paola & Macchi, Ennio, 2014. "Binary ORC (Organic Rankine Cycles) power plants for the exploitation of medium–low temperature geothermal sources – Part B: Techno-economic optimization," Energy, Elsevier, vol. 66(C), pages 435-446.
    15. Shaopeng Huang, 2012. "Geothermal energy in China," Nature Climate Change, Nature, vol. 2(8), pages 557-560, August.
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    1. Yuan Zhao & Chenghao Gao & Chengjun Li & Jie Sun & Chunyan Wang & Qiang Liu & Jun Zhao, 2022. "Energy and Exergy Analyses of Geothermal Organic Rankine Cycles Considering the Effect of Brine Reinjection Temperature," Energies, MDPI, vol. 15(17), pages 1-20, August.

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