Energy and exergy analyses of an advanced combined cycle fired by natural gas and biomass

Abstract

A modified combined cycle with an intercooler and a reheater (CCIR) within the gas-turbine system is proposed and evaluated. The fuel for the combustion chamber is natural gas, and the fuel for the reheater is provided by gasified biomass. Adding an intercooler between two compressors and a preheater for the compressed air before entering the combustion chamber increases the efficiency of the overall system. A further increase in efficiency was achieved through the utilization of the heat of the exiting hot gases in a Rankine cycle. The system has a fixed power output of 10 MW. The system's improvements resulted in 56.3% of the overall energy efficiency and 50.7% of the exergy efficiency. Natural gas and biomass flow rates are 0.139 kg/s and 0.776 kg/s, respectively.