Performance and parametric investigation of a binary geothermal power plant by exergy

Exergy analysis of a binary geothermal power plant is performed using actual plant data to assess the plant performance and pinpoint sites of primary exergy destruction. Exergy destruction throughout the plant is quantified and illustrated using an exergy diagram, and compared to the energy diagram. The sites with greater exergy destructions include brine reinjection, heat exchanger and condenser losses. Exergetic efficiencies of major plant components are determined in an attempt to assess their individual performances. The energy and exergy efficiencies of the plant are 4.5% and 21.7%, respectively, based on the energy and exergy of geothermal water at the heat exchanger inlet. The energy and exergy efficiencies are 10.2% and 33.5%, respectively, based on the heat input and exergy input to the binary Rankine cycle. The effects of turbine inlet pressure and temperature and the condenser pressure on the exergy and energy efficiencies, the net power output and the brine reinjection temperature are investigated and the trends are explained.

[1]  Mehmet Kanoglu,et al.  Exergy analysis of a dual-level binary geothermal power plant , 2002 .

[2]  A. Bejan.  Advanced Engineering Thermodynamics , 1988 .

[3]  Ronald DiPippo,et al.  Second Law assessment of binary plants generating power from low-temperature geothermal fluids , 2004 .

[4]  Mehmet Kanoglu,et al.  Economic evaluation of geothermal power generation, heating, and cooling , 1999 .

[5]  J. Kestin.  Available work in geothermal energy , 1978 .

[6]  Richard A. Gaggioli,et al.  Available Energy and Exergy , 1998 .

[7]  E. Barbier.  Nature and technology of geothermal energy: A review , 1997 .

[8]  Pavlos S. Georgilakis,et al.  Optimized geothermal binary power cycles , 2008 .

[9]  K. A. Phair.  Getting the most out of geothermal power , 1994 .

[10]  Mehmet Kanoglu,et al.  Retrofitting a Geothermal Power Plant to Optimize Performance: A Case Study , 1999 .

[11]  Zhaolin Gu,et al.  Performance of supercritical cycles for geothermal binary design , 2002 .

[12]  Ibrahim Dincer,et al.  Thermo-Mechanical Exergy Analysis of Balcova Geothermal District Heating System in Izmir, Turkey , 2004 .

[13]  Ronald DiPippo,et al.  Geothermal energy Electricity generation and environmental impact , 1991 .

[14]  E. E. Michaelides,et al.  The influence of seasonal and daily temperature fluctuations on the work produced by geothermal power plants , 1992 .

[15]  Michael J. Moran,et al.  Availability analysis: A guide to efficient energy use , 1982 .

[16]  Mehmet Kanoglu,et al.  Improving the performance of an existing air-cooled binary geothermal power plant : A case study , 1999 .

[17]  Efstathios E. Michaelides,et al.  Binary-Flashing Geothermal Power Plants , 1993 .

[18]  B. Mohanty,et al.  Economic power generation from low-temperature geothermal resources using organic rankine cycle combined with vapour absorption chiller , 1992 .

[19]  G. Bodvarsson,et al.  The exergy of thermal water , 1972 .

[20]  Keng Choon Lee,et al.  Classification of geothermal resources by exergy , 2001 .

[21]  K. Wark,et al.  Advanced thermodynamics for engineers , 1994 .

[22]  Arif Hepbasli,et al.  A key review on exergetic analysis and assessment of renewable energy resources for a sustainable future , 2008 .

[23]  Mehmet Kanoglu,et al.  Incorporating a District Heating/Cooling System Into an Existing Geothermal Power Plant , 1998 .

[24]  Arif Hepbasli,et al.  Energy and Exergy Analysis of Kizildere Geothermal Power Plant, Turkey , 2006 .

[25]  J. F. Kunze.  Utilizing geothermal resources below 150 C (300 F) , 1979 .