Thermodynamic analysis of a binary geothermal power plant


Ozcan Z., EKİCİ Ö.

INTERNATIONAL JOURNAL OF EXERGY, vol.36, no.1, pp.76-97, 2021 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 36 Issue: 1
  • Publication Date: 2021
  • Doi Number: 10.1504/ijex.2021.117605
  • Journal Name: INTERNATIONAL JOURNAL OF EXERGY
  • Journal Indexes: Science Citation Index Expanded, Scopus, Aerospace Database, Communication Abstracts, Compendex, INSPEC, Metadex, Civil Engineering Abstracts
  • Page Numbers: pp.76-97
  • Keywords: geothermal power plant, GPP, exergy analysis, plant analysis, cost estimation, THERMOECONOMIC ANALYSIS, PERFORMANCE ANALYSIS, EXERGY ANALYSIS, OPTIMIZATION, GENERATION, ENERGY, CYCLES

Abstract

A geothermal plant located in southwestern Turkey is evaluated from thermodynamic and economic perspectives. The first and second law efficiencies of the plant are calculated to be 4.82% and 25.7% respectively. On plant level, brine re-injection process is found out to be primarily responsible for exergy losses (21.9%). Major sources of losses at ORC systems are turbines and pumps (25.44%), heat exchangers (21.78%) and condensers (10.8%). Thermal losses from heat exchangers are calculated to be around 444 kW which corresponds 0.27% of heat transfer value at heat exchangers. Applicability of water-cooled condensers instead of existing air-cooled condensers is also discussed. Results indicate that it is possible to reduce the initial capital investment around 20%. Furthermore, it may be possible to further increase the exergetic efficiency of these hypothetical water-cooled condensers by increasing the rejection temperature and subsequently decrease initial capital investment by 1.4% and reduce heat release to the environment.