Operational Performance Analysis of a Grid-Assisted Solar Photovoltaic–Battery Hybrid System at Wasso, Ngorongoro District, Tanzania

This paper analyses a grid-assisted solar photovoltaic (PV)–lithium iron phosphate battery hybrid system at Wasso, Tanzania (altitude ≈ 1 900 m), combining one week of five-minute telemetry (1 605 samples over 174.5 hours) with a six-month record of daily energy statistics (166 operational days, January–July 2026). Energy flows come from numerical integration, cross-validated against the platform's daily statistics. During the intensive week the array generated 382.9 kWh against a load of 739.5 kWh, with 374.6 kWh imported and none exported; direct PV, battery discharge and grid import met 40.6, 16.5 and 42.7 per cent of demand. Because the battery is also float-charged from the grid, at most 51 per cent of the load is of solar origin, close to the net-import self-sufficiency of 49.3 per cent; PV self-consumption is 100 per cent. Usable capacity, estimated coulometrically, is 21.1 kWh, cycled daily to a 24–26 per cent state-of-charge floor at about 75 per cent depth of discharge. The load shows a 16.6 kW peak, a 5.11 kW mean, a 30.8 per cent load factor and a persistent overnight base served by the grid. The six-month record corroborates the week: the net-import renewable fraction is 51.6 per cent, the capacity factor 14.7 per cent over all operational days and 16.8 per cent in service, and the seasonal renewable fraction 47 to 64 per cent. Storage capacity, not PV generation, is the binding constraint on clear days; recommendations for battery augmentation and load management are quantified