engleski

Exergy Analysis of Electricity Generation by the Medium Temperature Geothermal Resources: Geothermal Power Plant Velika Ciglena Case Study

According to the numerous surveys, in the Republic of Croatia currently existing a certain number of medium temperatures geothermal fields (between 100 ºC and 180 ºC) suitable for electricity production. However, only recently concrete initiatives for the construction of geothermal power plants have been started. In order to explore the appropriate models for efficient electricity production in geothermal field of Velika Ciglena, detail description and specification of geothermal field, followed by short feasibility study for potential employment of ORC or Kalina binary cycles, are performed in the past. As continuation of that investigations, study presented in this paper analyze the thermodynamic performance of the both cycles by the two level simulation software, created on EES and Excel programming platform. Mathematical models of cycles are represented by a set of mass and energy balance equations and applied to the control volume for every of their main components. The degrees of freedom analysis of the both models are carried out to establish the maximum number of input variables in simulation task. The model configurations and working parameters of the cycles are chosen in such a way that they are very close to the performed, type-designed plants of the leading world manufacturers. The simulation results are than used for analysis of the cycles according to the first law of thermodynamic and for exergy analysis based on fuel-product concept. The results of analysis confirm the conclusion made in previous feasibility study that ORC cycle is thermodynamically more appropriate for electricity production in Velika Ciglena geothermal field.

geothermal energy; Velika Ciglena in Croatia; binary cycles; exergy analysis

nije evidentirano