Exergoeconomic analysis of the güre geothermal district heating system

Geothermal energy holds strategic importance as a renewable energy source that enables the utilization of domestic resources on a global scale. Its low carbon emissions, cost effectiveness, multi-purpose usability and ability to provide an uninterrupted energy supply throughout the year regardless of external conditions set geothermal energy apart from other renewable energy sources. In this study, energy, exergy, and exergoeconomic analyses were performed on the Güre Geothermal District Heating System (GDHS), located in the Güre neighborhood of Edremit, Balıkesir. The analyses were based on actual field measurement data collected on 28.01.2023. The energy and exergy efficiencies of the system were determined to be 72,61% and 64,11%, respectively. These values indicate that the system, while still possessing potential for improvement, operates with high energetic and exergetic efficiency. ,For the exergoeconomic analysis, the specific exergy costing (SPECO) method was employed, which allows for an exergoeconomic investigation of the system by determining the flow costs for each point and component defined on the system's flow diagram. It was determined that pumps 1 and 4 operate thermodynamically inefficiently due to their high exergy destruction costs of 22,34 $/h and 27,07 $/h, respectively, leading to additional increases in operational costs. Furthermore, heat exchangers 3 and 4 were found to reduce the overall cost-effectiveness of the system due to their high capital and operation-maintenance costs of 3,25 $/h and 3,68 $/h, respectively. Therefore, it was concluded that investments and operational improvements aimed at enhancing the thermodynamic efficiency of the specified pumps should be prioritized. Subsequently, implementing strategies to reduce the capital investment and maintenance costs of the heat exchangers could elevate the system's total cost-effectiveness to higher levels.