Performance analysis of DORA-4 geothermal power plant and investigation of optimum operating conditions by operational and modification techniques

The quality and regularity of energy are among the primary reasons for preference in energy demand. In this context, alternative energy resources geothermal energy is also renewable It is a renewable energy source that has been the most preferred in recent years in terms of being sustainable, clean and cheap, and even its installed power is increasing day by day. However, the structural and operational optimisation of power generation systems is as important as the selection or evaluation of energy sources, both in terms of obtaining maximum performance from the system and in terms of operation and maintenance costs. In this study, it is aimed to evaluate the performance status of DORA-4 Geothermal Power Plant located in Köşk district of Aydın in the current operating conditions and then to determine the optimum operating conditions of the plant by applying operation and modification techniques. In addition, it is aimed to provide an analysis methodology to producers and users within the scope of identifying the deficiencies, inadequacies and possible improvements of an existing system with the comprehensive analysis methods used in the study and the evaluations made. In the study, only the electrical power generation OEC (Ormat Energy Converter) section of the power plant, where the electrical power generation is realised, is examined, while the BOP (Balance of Plant) section, where the geothermal fluid is produced, is excluded. The performance analyses of the power plant are based on the actual operating parameters of the power plant and the basic energy and exergy equations and CoopProp application are used in the calculations. In the scope of investigating the performance improvement of the power plant, the results of the performance evaluation were taken as a basis and the plant was optimised both structurally and operationally by changing the turbine inlet parameters with the superheaters integrated into the cycles, using the EBSILON Professional programme developed by Steag GbmH. As a result of the detailed thermodynamic analyses, it was determined that the production capacity of the power plant decreases during the mild seasons, which is due to the inadequacy of the cooling system of the plant in the face of increasing air temperatures. In addition, it has been determined that the superheaters integrated into the plant do not contribute to the system due to the thermophysical properties of the existing working fluid. In other words, it has been found that the generation capacity of the power plant can be increased by 1 870 kW with an increase of 15,5 % even with only parametric improvements, without the need for any additional equipment. Finally, the plant was also evaluated in terms of economic and environmental aspects, and improvements were achieved in the economic and emission values of the plant with the optimisation study.