Exergy Analysis Using a Theoretical Formulation of a Geothermal Power Plant in Cerro Prieto, México

Area of Science:

• Thermodynamics
• Geothermal Energy Engineering
• Environmental Science

Background:

• Geothermal power plants harness Earth's heat for electricity generation.
• Optimizing energy conversion and minimizing losses are crucial for sustainable geothermal energy production.
• Exergy analysis provides a robust method for evaluating thermodynamic inefficiencies in power cycles.

Purpose of the Study:

• To calculate and compare exergy destruction in single-flash and double-flash geothermal power plant cycles.
• To identify components contributing most significantly to exergy destruction within these systems.
• To evaluate the thermodynamic performance (first and second law efficiencies) of both configurations.

Main Methods:

• Development of thermodynamic models for energy and exergy flows.
• Application of these models to analyze a geothermal power plant in Cerro Prieto, Mexico.
• Quantification of exergy destruction for each component in single-flash and double-flash cycles.

Main Results:

• The single-flash cycle exhibited first and second law efficiencies of 0.1888 and 0.3072, respectively.
• The double-flash cycle achieved higher efficiencies: 0.3643 (first law) and 0.4983 (second law).
• Condensers were the primary source of exergy destruction in both configurations; the low-pressure turbine also contributed significantly in the double-flash cycle.

Conclusions:

• The double-flash geothermal power plant cycle demonstrates superior thermodynamic performance compared to the single-flash cycle.
• Condenser inefficiency is a critical area for improvement in both single-flash and double-flash geothermal power systems.
• Targeted improvements in component performance, particularly the condenser and low-pressure turbine, can enhance overall geothermal power plant efficiency.