Energy and Exergy Appraisal of a 112.5MW Single Shaft Gas Turbine Power Plant in the Niger Delta, Nigeria

This research presents a thermodynamic appraisal of a 112.5 MW Gas Turbine (GT) Plant through energetic and exergetic analyses utilizing the average operational data for ten (10) years. The components of the GT plant were simplified into control volumes and energy and exergy inflows and outflows, applying the first and second laws of thermodynamics, respectively. The results of the energy analysis showed that a 3.16oC rise in ambient temperature resulted in 10.99% drop in thermal efficiency and 27.92% drop in net power output, indicating a decline in both performance parameters with an increasing ambient temperature. The result of the exergetic analysis revealed that on average, every 1oC increase in ambient temperature resulted in a 0.95% rise in the overall exergetic destruction growth and a 3.22% drop in the overall exergetic efficiency. It was found that a high level of irreversibility in the combustion chamber (CC) is responsible for the low overall exergetic efficiency and the increment in the overall exergy destroyed. By raising the turbine inlet temperature, the high exergy destruction in the CC can be reduced to improve the GT performance. Hence, for performance optimization, measures to reduce the exergetic destruction rate within the combustor should be put in place. The study provides performance-based guides for energy managers and investors for critical decision-making