Umudike Journal of Engineering and Technology

The study presents the energy utilization efficiency and performance of selected utility based thermal plants in Nigeria using energy and exergy method. The exergy concept in recent times is recognized as a veritable tool for actualizing sustainable development. In this background, the exergy flows in the Nigerian utility sector (NUS) were studied from 2001 to 2013. The variations in the efficiencies were estimated for the gas turbine (GT), steam turbine plants (ST), and combined power plants (CPP).The results obtained indicatethe overall energy and exergy efficiencies for the utility sector varies from 27.2 to 28.70 % and 25.9 to 27.30 %,respectively with average efficiency margins of 1.35 %. The latter shows that there exist a high potential for system improvement and efficiency enhancement. Conversely, the improvement potential (IMP) of the Nigerian utility sector (NUS) for the considered period were estimated at 16286TJ in 2001 and 14745TJ in 2013. It can be inferred that the exegetic approach applied in this study is worthwhile in evaluating the sector efficiency and ascertaining the degree of energy and exergy usage. Findings from this study are believed will provide informed decision support for effective energy policy and thus enhance sustainable development.