Hybrid Electricity Generation System for The Gali Zakho Tunnel in Iraq: A Comparative Study of Different Configurations Using Homer Pro
Document Type : Research Article
Authors
1 Environmental Science Department, College of Science, University of Zakho, Duhok, Iraq.
2 Department of Environmental Science, College of Science, University of Zakho, Duhok, Iraq
3 Department of Computer Science, University of Zakho, Dohuk, Iraq
Abstract
This paper explores the feasibility of a renewable hybrid power plant for the Gali zakho highway tunnel in the north of Iraq. HOMER Pro was used to simulate, optimize, and evaluate the off-grid technical, economic, and environmental performances of seven hybrid system configurations. The investigations revealed that Case A (PV–Diesel–Battery) was the best configuration not only because of its lowest Net Present Cost ($ 6.68 M) but also because it has a Cost of Energy of $0.065/kWh, with an IRR of 18% and an ROI of 14% and a simple payback period of 5.2 years for a 25-year project lifetime. The system generated about 9,440,000 kWh a year, and PV panels accounted for 97.4% of the total, leading to a system renewable fraction of 94.8%, while the generating diesel accounted for only the remaining 2.6% by acting as a backup power source. The top-performing configuration reduced CO₂ emissions by nearly 3.7 million kg per year versus generators that ran on diesel alone and still delivered reliable power. These results validate the applicability of PV-biased hybrid systems for tunnel infrastructure and identify their potential contribution to sustainable energy development in northern Iraq.
Keywords
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