Keywords: combined heat and power, CHP, energetic efficiency, exergetic efficiency, intercooled, reheat, regeneration, indirect fired air turbines, energy efficiency, exergy, first law, second law, thermodynamics, pressure losses, process steam pressure
Energetic and exergetic efficiency analysis of an indirect fired air-turbine combined heat and power system
The aim of this paper is to analyse the performance of an intercooled reheat regenerative indirect fired air turbine based combined heat and power system using the first and second law of thermodynamics. The energetic and exergetic efficiencies have been defined. The effects of overall pressure ratio, cycle temperature ratio, pressure losses and process steam pressure on the energetic and exergetic efficiencies have been investigated. The results indicate that the first-law efficiency is approximately independent of pressure losses, but the second-law efficiency and the power to heat ratio reflects the fact that the higher-pressure drops degrade the thermodynamic performance significantly. Energetic efficiencies are approximately independent of process steam pressure, but the exergetic efficiency increases with the same.