Techno-Economic and Exergo-Environomic Assessment of Gas Turbine Plants for Power Generation in the Niger Delta

Le-ol Anthony Kpegele¹, Stanislaus Chinemerem Philip²

^1-2 Department of Mechanical Engineering, Rivers State University, Port Harcourt, Rivers State, Nigeria.

Abstract

Gas turbine power plants dominate electricity generation in Nigeria’s Niger Delta, yet their performances are affected by inefficiencies and significant environmental impacts under tropical conditions. This study conducts a techno-economic, exergy and environmental assessment of three gas turbine plants (Afam, Ibom, and Sapele II) for Power Generation. It utilises exergy analysis and exergo-economic modeling to evaluate efficiency losses, emissions, and cost implications. Exergy analysis reveals that combustion chambers and turbines account for over 70% of exergy destruction, primarily due to high irreversibility and cooling air losses, contributing to elevated CO₂ and NOₓ emissions. The waste exergy ratio links these inefficiencies to economic penalties, showing that a 10% reduction in exergy destruction could lower electricity costs by up to 8% while reducing emissions by 12%. Life cycle cost (LCC) analysis indicates that capital expenditure (CAPEX) dominates at $93.3–$123.6 million across the plants, with fuel costs ($39.2–$85.4 million) as the second-largest driver. However, thermo-economic modeling findings suggest that combined-cycle retrofits and inlet air cooling could improve thermal efficiency by 15–20% and reduce environmental penalties under carbon pricing scenarios. Hence, the findings in this research highlight the need for integrated solutions, including advanced combustion technologies and reliable gas supply, to enhance sustainability. By quantifying the interplay between exergy losses, emissions, and costs, this study provides a robust framework for optimizing gas turbine operations in the Niger Delta, offering evidence-based insights for policy, design, and investment decisions to align with Nigeria’s energy and environmental goals.

Keywords: Gas turbine, Energy generation, Thermo-Techno-Economic Assessment, Environmental implications, Niger Delta Electricity sector

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