Exergy based parametric analysis of a combined reheat regenerative thermal power plant and water–LiBr vapor absorption refrigeration system

• Published in: Energy conversion and management 2014-07, Vol.83, p.119-132
• Main Authors: Gogoi, T.K., Talukdar, K.
• Format: Article
• Language: English
• Subjects: Applied sciences; Boilers; Energy; Energy. Thermal use of fuels; Evaporation; Exact sciences and technology; Exergy; Exergy analysis; Generators; Installations for energy generation and conversion: thermal and electrical energy; Law; Regenerative; Reheat regenerative power cycle; Steam electric power generation; Thermal power plants; Vapor absorption refrigeration system; VAR; Water–lithium bromide
• ISSN: 0196-8904; 1879-2227
• DOI: 10.1016/j.enconman.2014.03.060

•Exergy analysis of a combined power–absorption cooling system is provided.•Exergetic efficiency of the power cycle and absorption cooling system are calculated.•Irreversibility in each component and total system irreversibility are calculated.•Effect of operating parameters on exergetic performance and irreversibility is analyzed.•Optimum operating parameters are identified based on energy and exergy based results. In this paper, exergy analysis of a combined reheat regenerative steam turbine (ST) based power cycle and water–LiBr vapor absorption refrigeration system (VARS) is presented. Exergetic efficiency of the power cycle and VARS, energy utilization factor (EUF) of the combined system (CS) and irreversibility in each system component are calculated. The effect of fuel flow rate, boiler pressure, cooling capacity and VARS components’ temperature on performance, component and total system irreversibility is analyzed. The second law based results indicate optimum performance at 150bar boiler pressure and VARS generator, condenser, evaporator and absorber temperature of 80°C, 37.5°C, 15°C and 35°C respectively. The present exergy based results conform well to the first law based results obtained in a previous analysis done on the same combined system. Irreversibility distribution among various power cycle components shows the highest irreversibility in the cooling tower. Irreversibility of the exhaust flue gas leaving the boiler and the boiler are the next major contributors. Among the VARS components, exergy destruction in the generator is the highest followed by irreversibility contribution of the absorber, condenser and the evaporator.