Economic Evaluation of Rooftop Solar PV Investment for Commercial Properties in Abuja, FCT

This study conducts a detailed economic evaluation of rooftop solar photovoltaic investment for commercial property owners in Abuja, Federal Capital Territory, providing a framework for investment decision-making in Nigeria's evolving electricity market. Commercial properties in Abuja rely heavily on diesel generators due to unreliable grid supply, and rising electricity tariffs combined with falling PV system costs are shifting the economics of rooftop solar significantly. A representative portfolio of five commercial properties including office buildings, a hotel, and a retail centre was selected as case studies. For each property, the energy consumption profile was established from billing records and on-site metering, the available rooftop area was surveyed, and a customised PV system design was developed using PVsyst simulation software. Financial modelling employed net present value, internal rate of return, discounted payback period, and levelised cost of energy calculations over a 25-year analysis horizon under base case and sensitivity scenarios covering electricity tariff escalation, PV cost variations, and solar irradiance uncertainty. Results show that rooftop PV investment yields positive net present values for all five properties under the base case scenario, with internal rates of return ranging from 18 to 27 percent, significantly exceeding the commercial borrowing rate in Nigeria. Discounted payback periods range from 4.2 to 6.8 years. Sensitivity analysis identifies electricity tariff escalation as the most influential variable, with each 10 percent tariff increase improving the IRR by approximately 2.5 percentage points. Keywords: solar PV, economic evaluation, rooftop installation, commercial property, Abuja.