Technical and Economic analysis of solar PV electricity generation under the net metering scheme at Sunyani Teaching Hospital (STH), Ghana

Abstract

The unreliable power supply, high cost of electricity and non-payment of electricity bills among the state-owned hospitals in Ghana badly affects health services delivery. Meanwhile, hospitals can obtain reliable electricity and reduce their bills using rooftop solar PV systems technology, yet little attention has been given to this in Ghana. This study aims to technically and economically assess the feasibility and viability of implementing rooftop solar PV electricity under the net metering programme that Ghana recently adopted for hospitals. The study uses a case study (Sunyani Teaching Hospital) through empirical technical assessment (Google Earth Pro software, load profiles and grid connection option) and engineering econometrics (Net present value - NPV, Internal rate of return - IRR, Discounted payback period - DPP and profitability index - PI) to arrive at its conclusion. The technical results show that the Sunyani Teaching Hospital has a total installed load of 297,471 kW and an annual energy demand of 1,493,326 kWh. The proposed PV plant can produce about 9,418,145 kWh of energy per year. The economic results show an NPV of GHS 64.09 million, IRR of 34%, PI of 2.4, and DPP of 4 years for the system configuration without battery storage, while an NPV of GHS 61.21 million, IRR of 28%, PI of 2.3, and DPP of 4 years for the system configuration with 10% battery storage capacity. The solar PV system's resultant annual carbon dioxide savings from the study is 8,005,423.34 kg, while a 200,135,588.38 kg carbon reduction can be achieved in the project's lifetime. The economic evaluation of the proposed solar PV microgrid using carbon credit resulted in higher profitability. An NPV of GHS 72.89 million, IRR of 36%, PI of 2.6, and DPP of 4 years were realized by considering carbon credit in the analysis the system configuration without battery storage. At the same time, the system configuration with 10% battery storage capacity an NPV, IRR, PI, and DPP of GHS 70.04 million, 32%, PI 2.5, and 4 years, respectively. The results show that the net present values for cases with 50% storage, and 100% storage are GHS 70.0 million, GHS 58.6 and GHS 44.4 million, respectively. Similarly, IRRs 32%, 22% and 14% were obtained in the order of the above cases. Again, the PI obtained are 2.5, 2.0, and 1.6 in order of the above cases, and lastly, the period for the investment recovery is 4 years, 5 years, and 6 years, respectively. The results indicate that hospitals in developing countries can leverage of rooftop solar PV system to enhance their health services delivery.