Assessment of Economic Impact and Efficiency of a Combined Gas Turbine with a Thermoelectric Generator
Onoroh Francis, Ikebudu Kingsley O., and Okafor I.O.U
Abstract– The research presents how to scavenge waste heat from a gas turbine plant using a thermoelectric generator and to assess the economic implication. On comparing the equivalent uniform annual worth of the combined GT/TEG with GT only, the annual disbursement for the GT/TEG is $2,288,231.908 and for the GT only is $2,316,738.107. Therefore, the combined GT/TEG is found to be more economical. The gas turbine whose operating condition was used for the design of the thermoelectric generator is based at Ughelli Thermal power station, Ughelli, Delta state, Nigeria. Also, the efficiency of the gas turbine was increased from 0.342 to 0.453 with the introduction of a thermoelectric generator containing lead telluride modules. Keywords– Economic Analysis, Efficiency, Gas Turbine, Thermoelectric Generator, Sankey Diagram and Equivalent Uniform Annual Worth
I.
INTRODUCTION
I
ncreased overall plant efficiency is possible by coupling a thermoelectric generator to an existing gas turbine plant. A combined GT/TEG system is more economical than a GT only. One way to improve the sustainability of electricity base is through the scavenging of waste heat with thermoelectric generators i.e. thermoelectric materials. Gas turbine exhaust, automotive exhaust, steam turbine and industrial processes all generate waste heat that could be converted to electricity using thermoelectric generator. Fig. 1 shows the Sankey diagram for most thermal engine plant. Up to 40% of the combustion energy supplied leaves in the exhaust. Furthermore, the exhaust temperature is much greater than that of the other heat rejection streams; therefore, the potential conversion efficiency of a bottoming cycle connected to this stream is