Evaluating the effect of productive use of energy of optimal mini-grids and sizing in rural areas of Uganda

Access to reliable electricity remains a critical challenge in rural Uganda, where approximately 58% of the population lacks grid connectivity, constraining socio-economic progress. This study evaluates the effect of productive use of energy (PUE) through optimally sized solar mini-grids in rural Uganda, using a case study in Kasanje Sub-County, Entebbe Municipality. Employing a mixed-methods approach underpinned by a crosssectional design, the study integrated questionnaire surveys of 25 business operators, field observation of 12 energy-consuming enterprises, and simulation using PVsyst v7.4.7. A 720 kWp standalone photovoltaicbattery mini-grid, designed to supply 4,000 kWh per day, was modelled and validated. Results indicate that solar mini-grid power costs approximately UGX 322 per kWh compared to UGX 575 per kWh for utility power over 20 years, a saving of over 44%. The system achieved a Solar Fraction of 95.54% and a Performance Ratio of 77.86%, confirming technical viability. Productive use of energy extended business operating hours by 50%, significantly boosting milling and processing output. The study concludes that optimally designed solar mini-grids can catalyse economic growth, improve access to education, healthcare, and clean water, and contribute to Uganda’s national electrification targets, provided they are supported by appropriate policy incentives, financing mechanisms, and community capacity-building programmes.