Thermodynamic analysis of a novel semi-closed loop gas turbine conventional hybrid cycle: 4E-S approach (energy, exergy, economics, emissions, and sustainability)

Abstract

In rural areas, which often have limited access to reliable electricity, gas-turbine hybrid cycles can provide a more stable and consistent source of power. India is a developing country, and its energy demands are increasing day by day. The economy of a country depends on energy consumption. To bridge the demand–supply gap and enhance the economy, a hybrid power generation system is proposed. A high-temperature fuel-cell is integrated with the conventional gas-turbine to improve its efficiency by more than 50%. A MATLAB-based simulation fuel-cell model is validated and then integrated with the gas turbine cycle. Performance can be assessed both quantitatively and qualitatively using the first and second laws of thermodynamics, respectively. The impact of pressure ratio and turbine inlet temperature on various operating parameters is discussed. The network output increases as the pressure ratio increases due to the greater expansion of combusted gas in the gas turbine. Solid oxide fuel cell work can increase energy efficiency by 41.27%. The hybrid system maximizes energy (63.78%) and exergy (60.17%) efficiency at pressure ratio 6. The combustion chamber achieved the highest rate of exergy destruction, at 56.8% in the semi-closed loop gas turbine and 61.7% in the semi-closed loop hybrid gas turbine. At the end of this work, an economic and emissions (CO and NOx) comparison between the two proposed configuration is presented. Also, a unique performance and emissions map are discussed.