Performance Evaluation of Gas Turbine Units in a Nigerian Power Plant: A Comparative Energy, Exergy, and Reliability Approach

This study comparatively analysis the performance of two of the gas turbine units (GT 16 and GT19) in the Delta IV power plant, Nigeria. The comparative analysis was carried out from the energetic, exergetic and reliability viewpoint. The comparative thermodynamic analysis of the units based on first law (energy) and second law (exergy) performance indices was carried out. The results of energy analysis of GT16 & GT19 revealed that the thermal efficiency, heat rate, power, specific fuel consumption, and work ratio respectively are 25.6%, 13.7 MJ/KW-h, 98.0 MW, 0.289 Kg/KW-h, 0.403 and 26.6%, 13.5 MJ/KW-h, 98.8 MW, 0.286 Kg/KW-h, 0.401 respectively. Also, exergy analysis of GT16 & GT19 showed that the turbine had the largest exergy efficiency of 94.3% and 94.7% respectively, while the combustion chamber had the highest exergy destruction of 39.6% and 39.2% respectively. The Weibull reliability analysis method was also used in evaluating the reliability of each unit after which the results were compared. Average reliability of GT19 over the studied period was 68.1% while that of GT16 was 66.5%, indicating better performance from GT19 in terms of the thermodynamic efficiency and reliability analysis