Feasibility and techno-economic analysis of PV-battery priority grid tie system with diesel resilience: A case study

Ethiopia is close to the equator and has enormous potential as a solar energy resource that has yet to be realized. The country has some small-scale diesel-based power generation, and all universities and government agencies have installed standby generator sets for supplying power when the grid is interrupted. Ethiopia is a developing nation with a significant reliance on oil imports and insufficient rural electrification, which exacerbates the problem of poverty. The increased cost of oil, frequent hard currency expenditures for oil, and exaggerated maintenance costs for the generators are the main reasons to undertake this feasibility study. As the assessments show, the annual average interruption was more than 800 h in the past five years in the Debre Markos University distribution feeder. A preliminary study on the techno-economic feasibility of the existing diesel generator set and PV system with the same rated power of 500 kW is conducted in this work. As the break-even point of the economic comparison shows, the existing diesel generator is not economically feasible as compared to the proposed PV-battery priority grid tie system due to high running and service costs. The study also shows the technical feasibility of solar energy, as the P-V and I-V characteristic curves illustrated on a single standard solar module indicate. As the economic comparison break-even point shows, the diesel-based generator set is not economical after 5 years due to the high operational and maintenance costs. As the results show, the proposed PV/Battery Priority system with a diesel generator for resilience is more environmentally friendly, reducing the carbon footprint by 94%.