Assessment of performance indices of selected gas turbine power plants in Nigeria

Abstract

In this study, performance assessment of selected gas turbine power plants in Nigeria was evaluated using performance indices. The results of the study showed that for the period under review (2006)(2007)(2008)(2009)(2010), the percentage shortfalls from the target energy in the selected power plants range from 26.33% to 86.61% as against the acceptable value of 5-10%. The capacity factor of the selected power plants varies from 16.88% to 73.67% as against the international value of 50-80%. The plant use factor varies from 45.89% to 97.03% and the utilization factor varies from 6.31% to 93.074% as against the international best practice of over 95%. From this result, it can be concluded that the generating units were underutilized. This is due to inadequate routine maintenance and equipment fault development. The analyses of reliability indicators revealed that the mean time between failures varies from 5.42 to 378.44 h, the mean time to repair varies from 18.3 to 153.88 h and the plant availability varies from 12.86% to 91.31% as against the Institute of Electrical and Electronics Engineers recommended standard of 99.9%. Evaluation of operating figures of the selected power plants revealed that starting reliability (SR) and operating reliability vary from 71.95% to 93.9% and 5.33% to 55%, respectively. The SR of the selected power plants is low in value compared with standard value of 99.9%. The statistical analysis carried out on plant availability revealed that at 95% confidence level; there is a significant difference in availability of the selected power plants. This indicates differences in their systems installation, operation and maintenance. The performance indicator developed to evaluate the performance indices for the selected stations can also be applicable to other power stations in Nigeria and elsewhere. Measures to improve the performance indices of the plants have been suggested in this paper.

Performance Evaluation of Alaoji Thermal Power Plant

“…The shortfall in energy generation for the period under review ranges from 1.4% to 90.5% with an average of 59.2% (Table 2). This is higher when compared with 26.33-86.61% obtained by Oyedepo in his assessment of selected gas turbines (Oyedepo, 2015). It is also in excess of the average acceptable value of between 5% and 10% (ICA, 2011).…”

Design and Assessment Methodology for System Resilience Metrics

“…Researchers use lognormal and exponential probability distributions for TTR (O'Connor, ). We collected the mean TTR (MTTR) of each generator (unit) (Buchta, Oziemski, & Pawlik, ; Cadwallader, ; Oyedepo, Fagbenle, & Adefila, ; Podofillini, Sudret, Stojadinovic, Zio, & Kröger, ) and we fit an exponential probability distribution for the TTR. We assume that the generator is operable after this TTR.…”

Performance Assessment and Economic Analysis of a Gas-Fueled Islanded Microgrid—A Malaysian Case Study

“…The average capacity factor of the UTP microgrid was 57.73%, as compared tothe industry best practice, which is between 50-80% [2,18,28]. For the economic operation of the microgrid, a high capacity factor is desirable, as the characteristic behavior of generating plant depends substantially on the utilization factor, as well as the capacity factor.…”

“…However, the study made no attempt to deal with an economic analysis. Although an economic analysis of gas-fueled power plants was presented in [17,18], the costs (i.e., fuel costs) due to non-optimal production were not been analyzed. Additionally, these studies focused on large-scale generation systems.…”