Performance Evaluation of Natural Gas Utilization in Power Generation As Strategy For Managing Gas Flaring in Nigeria

ABSTRACT       

This Study examines the performance evaluation of natural gas utilization in Power generation as strategy for reducing Gas flaring in Nigeria. The evaluation method comprises of use of Modular Gas Technology (MGT) plant for flare gas capture and processing, use ofthe processed gas in Turbine for power generation andappraisal of investments on MGT plant that consider profitability as well as time value of money. Technical performance of this technology was evaluated in terms of; (i) efficiency, (ii) fuel usage, (iii) thermal loses, (iv) methane recovery, (v) Natural gas feed requirements of the MGT and (vi) in recovery of stranded gases, while the economic profitabilitywas analyzed in terms of (i) Cash flow, (ii) NPV, (iii) POT and (iv) IRR. Models/Computer programs were developed and used for technical and economic calculations.Technically, the study shows that with MGT;flare and stranded gases are efficiently and profitably exploited and monetized, methane yield (for power generation) increased from initial 86% to 96% with MGT and further to 99%withinstallation of cracking unit to the MGT unit. It alsoshows that establishment of one(1) unit of 20mmscfd MGTperstate in Nigeria will lead to 98% reduction of gas flaring, while additional 1,632MW will be generated and added to our National grid systemif 20mmscfd MGT gasis used in Combined Cycle Gas Turbine (CCGT) per state for power generation, thus increasing availability of power supply. Economically, thestudyshows detail cash flow of flare gas projects, revealing the financial requirementsand expected revenue for a flare gas recovery and monetization for 20MMscfd MGT unit.At high tax and discount rates, the project yielded positive NPV and IRR with low POT of below five (5) years. Through this research, a new formula for calculation of POT (considering future time value of money) was developed. Lastly, the results of study show that prospect of naturalgas monetization using MGTis technically feasible, commerciallydesirable and economically profitable.