ABSTRACT

The exergy concept in recent times is recognized as a veritable tool for actualizing sustainable energy development goals. This concept is based on the first and second laws of thermodynamics. Additionally, the approach has the advantage of locating and quantifying irreversibilities in thermal systems thereby proffering solutions for system optimization. However, this research investigate the energy utilization efficiency and improvement potential of the Nigerian energy utility sector. 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 indicate the 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 (IP) of the Nigerian utility sector (NUS) for the considered period were estimated at 16286TJ in 2001 and I4745TJ in 2013. It can be inferred that the exergetic 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 is believed will provide informed decision support for effective energy policy and thus enhance sustainable development.