An Assessment of Grid-Charged Inverter-Battery Systems for Domestic Applications in Ghana

Abstract

Ghana, like many African countries, is currently facing power supply shortage, which has led to load shedding. To minimize the impact of the power crisis, options such as diesel and petrol generators, grid-charged battery-inverter systems (GBIS), and solar PV with battery storage (SPVS) have been used in residential and nonresidential contexts. In this paper, we develop analytical models to conduct a technical and economic comparison of GBIS and SPVS systems. Using average electricity tariff of $ 0.186 for residential sector (excluding lifeline customers) we show that although initial cost of SPVS is higher, it costs 30% less than GBIS. We also show that losses associated with the GBIS are as high as 42% when viewed from a systems perspective and that some of its costs are externalized. We conclude by commending the Ghana Government’s initiative of rolling out 200,000 residential rooftop solar systems and recommend an increase in system capacities as well as a similar programme for nonresidential facilities.