Assessing the Effect of Cooling Techniques on Performance Improvement of a Binary Geothermal Power Plant by Using Exergy-Based Analysis

Geothermal energy is a renewable and sustainable resource, but its efficient utilization is often constrained by operational inefficiencies and inadequate system management, highlighting the need for detailed energy assessments to improve performance and ensure long-term sustainability. This study aims for a comparative assessment of the performance of a binary geothermal power plant (GPP) considering air-cooled and evaporative cooling configurations using exergy analysis, based on real operating data. Exergetic parameters were applied to evaluate both overall system efficiency and the performance of individual components. The effect of geothermal fluid mass flow rate on turbine net power output was investigated. Additionally, a carbon emission analysis was conducted to assess environmental impact. Based on the energy content of the geothermal fluid entering the heat exchanger, the plant’s energy efficiency was calculated to be 7.5% for the air-cooled condenser configuration and 8.5% for the evaporative condenser configuration. On the basis of the heat input to the Rankine cycle, the overall energy efficiencies of the plant were found to be 39.76% and 43% for the air-cooled and evaporative condenser cases, respectively. The findings suggest that the overall exergy efficiency of the plant improves when employing the evaporative cooling system, reaching 53.57% compared to 48.38% for the air-cooled system. In the air-cooled configuration, Condenser I accounted for the highest exergy destruction at 27%, whereas in the evaporative system, Vaporizer II had the largest share at 25%. Furthermore, it was determined that the plant with an evaporative cooling system produced approximately 13% less carbon emissions compared to the air-cooled plant, which represents an advantage in terms of environmental sustainability.