Exergy analysis of two water pumps from steam power plant at four different loads

  • 1 Faculty of Engineering, University of Rijeka, Vukovarska 58, 51000 Rijeka, Croatia
  • 2 University of Zadar, Maritime Department, M. Pavlinovića 1, 23000 Zadar, Croatia


Paper presents exergy efficiency and loss analysis of condensate extraction pump (CEP) and main boiler feed pump (BFP) from a conventional steam power plant. Based on the required measured operating parameters at four different loads, it was observed that an increase in driving power for both pumps follows an increase in power plant cumulative developed power. Both analyzed pumps do not have the highest exergy losses at the highest observed load, as can be usually expected. Main boiler feed pump has the highest exergy efficiency, which is equal to 87.00%, at power plant nominal load, while the highest exergy efficiency of condensate extraction pump (95.77%) was observed at 60% of power plant nominal load. The influence of the ambient temperature on both pumps exergy efficiencies and losses is almost negligible.



  1. Kowalczyk, T., Ziółkowski, P., Badur, J.: Exergy Losses in the Szewalski Binary Vapor Cycle, Entropy 17, p. 7242-7265, 2015. (doi:10.3390/e17107242)
  2. Mrzljak, V., Poljak, I., Mrakovčić, T.: Energy and exergy analysis of the turbo-generators and steam turbine for the main feed water pump drive on LNG carrier, Energy Conversion and Management 140, p. 307–323, 2017. (doi:10.1016/j.enconman.2017.03.007)
  3. Mrzljak, V., Poljak, I., Medica-Viola, V.: Efficiency and losses analysis of low-pressure feed water heater in steam propulsion system during ship maneuvering period, Scientific Journal of Maritime Research 30, p. 133-140, 2016. (doi:10.31217/p.30.2.6)
  4. Koroglu, T., Sogut, O. S.: Conventional and Advanced Exergy Analyses of a Marine Steam Power Plant, Energy 163, p. 392- 403, 2018. (doi:10.1016/
  5. Mrzljak, V., Poljak, I., Medica-Viola, V.: Thermodynamical analysis of high-pressure feed water heater in steam propulsion system during exploitation, Shipbuilding 68 (2), p. 45-61, 2017. (doi:10.21278/brod68204)
  6. Poljak, I., Orović, J., Mrzljak, V.: Energy and Exergy Analysis of the Condensate Pump During Internal Leakage from the Marine Steam Propulsion System, Scientific Journal of Maritime Research 32 (2), p. 268-280, 2018. (doi:10.31217/p.32.2.12)
  7. Uysal, C., Kurt, H., Kwak, H. Y.: Exergetic and thermoeconomic analyses of a coal-fired power plant, International Journal of Thermal Sciences 117, p. 106-120, 2017. (doi:10.1016/j.ijthermalsci.2017.03.010)
  8. Mrzljak, V.: Low power steam turbine energy efficiency and losses during the developed power variation, Technical Journal 12 (3), p. 174-180, 2018. (doi:10.31803/tg-20180201002943)
  9. Mrzljak, V., Prpić-Oršić, J., Senčić, T.: Change in Steam Generators Main and Auxiliary Energy Flow Streams During the Load Increase of LNG Carrier Steam Propulsion System, Scientific Journal of Maritime Research 32 (1), p. 121-131, 2018. (doi:10.31217/p.32.1.15)
  10. Szargut, J.: Exergy Method - Technical and Ecological Applications, WIT Press, 2005.
  11. Mrzljak, V., Senčić, T., Žarković, B.: Turbogenerator Steam Turbine Variation in Developed Power: Analysis of Exergy Efficiency and Exergy Destruction Change, Modelling and Simulation in Engineering 2018. (doi:10.1155/2018/2945325)
  12. Mrzljak, V., Poljak, I., Prpić-Oršić, J.: Exergy analysis of the main propulsion steam turbine from marine propulsion plant, Shipbuilding Vol. 70., No. 1, p. 59-77, 2019. (doi:10.21278/brod70105)
  13. Tan, H., Shan, S., Nie, Y., Zhao, Q.: A new boil-off gas re liquefaction system for LNG carriers based on dual mixed refrigerant cycle, Cryogenics 92, p. 84–92, 2018. (doi:10.1016/j.cryogenics.2018.04.009)
  14. Mrzljak, V., Poljak, I., Medica-Viola, V.: Dual fuel consumption and efficiency of marine steam generators for the propulsion of LNG carrier, Applied Thermal Engineering 119, p. 331–346, 2017. (doi:10.1016/j.applthermaleng.2017.03.078)
  15. Orović, J., Mrzljak, V., Poljak, I.: Efficiency and Losses Analysis of Steam Air Heater from Marine Steam Propulsion Plant, Energies 2018, 11 (11), 3019 (doi:10.3390/en11113019)
  16. Mrzljak, V., Poljak, I., Medica-Viola, V.: Energy and Exergy Efficiency Analysis of Sealing Steam Condenser in Propulsion System of LNG Carrier, International Journal of Maritime Science & Technology "Our Sea" 64 (1), p. 20-25, 2017. (doi:10.17818/NM/2017/1.4)
  17. Mrzljak, V., Poljak, I., Žarković, B.: Exergy Analysis of Steam Pressure Reduction Valve in Marine Propulsion Plant on Conventional LNG Carrier, International Journal of Maritime Science & Technology "Our Sea" 65(1), p. 24-31, 2018. (doi:10.17818/NM/2018/1.4)
  18. Sengupta, S., Datta, A., Duttagupta, S.: Exergy analysis of a coal-based 210 MW thermal power plant, International journal of energy research 31, p. 14-28, 2006. (doi:10.1002/er.1224)
  19. Lemmon, E. W., Huber, M. L., McLinden, M. O.: NIST Reference Fluid Thermodynamic and Transport Properties REFPROP, Version 9.0, User’s Guide, Colorado, 2010.

Article full text

Download PDF