Thermo-Exergy Analysis and Comparison of Single-Stage and Two-Stage Flash Geothermal Power Plants: A Case Study on Power Plant

Authors

  • Fatemeh Aminipour * Faculty of Mechanical & Energy Engineering, Shahid Beheshti University, Tehran, Iran.
  • Asma Mozaffari Faculty of Mechanical & Energy Engineering, Shahid Beheshti University, Tehran, Iran.
  • Reza Alizadeh Khenesloo Faculty of Mechanical & Energy Engineering, Shahid Beheshti University, Tehran, Iran.
  • Ali Jahangiri Faculty of Mechanical & Energy Engineering, Shahid Beheshti University, Tehran, Iran.
  • Mohammad Ameri Faculty of Mechanical & Energy Engineering, Shahid Beheshti University, Tehran, Iran.

https://doi.org/10.22105/jeee.v2i2.36

Abstract

This article investigates the thermo-exergy and compares single-stage and two-stage cycles using operational data from a flash geothermal power plant. Results indicate that while both cycles use the same amount of geothermal energy to generate electricity, the two-stage flash cycle produces 43.7% more electrical power than the single-stage flash cycle. In addition, in terms of the single-stage cycle, the most considerable exergy loss occurs in the reinjection process, in which 40.3% of available exergy, which might have contributed to the work output otherwise, is directly reinjected into the reinjection well from the outlet of the separator. In contrast, for the two-stage cycle, the most considerable exergy loss occurs in the condenser with 20% of the available exergy. In addition, the single-stage cycle efficiencies concerning the first and second laws are obtained as 6.456% and 29.28%, respectively, while these values rise to 10.67% and 47.11%, respectively, for the two-stage cycle. This indicates that the first and second law efficiencies in the two-stage cycle are 39.4% and 37.8% higher than those in the single-stage cycle, respectively. This means that the two-stage cycle is more capable of generating power from a given amount of geothermal energy.

Keywords:

Thermo-exergy, Geothermal, Flash evaporation

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Published

2025-06-10

Issue

Articles in Press

Section

Articles

How to Cite

Aminipour, F., Mozaffari, A., Alizadeh Khenesloo, R., Jahangiri, A., & Ameri, M. (2025). Thermo-Exergy Analysis and Comparison of Single-Stage and Two-Stage Flash Geothermal Power Plants: A Case Study on Power Plant. Journal of Environmental Engineering and Energy. https://doi.org/10.22105/jeee.v2i2.36

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