OFF-GRID SOLAR PHOTOVOLTAIC PUMPING FOR SMALL-SCALE IRRIGATION IN SHANI, BORNO STATE

Abstract

This study evaluated the technical performance, hydraulic delivery reliability and economic viability of an off-grid solar photovoltaic (PV) pumping system against a conventional petrol pump. Six fadama farm sites were monitored from February to April during the dry season. Solar irradiance, PV output, discharge and dynamic total head were measured using a calibrated pyranometer, ultrasonic flow meter and piezometric pressure transducers. The 1.2 kWp PV system recorded a mean daily solar resource of 6.31 ± 0.42 kWh/m²/day, mean array efficiency of 14.2 ± 0.6% and mean performance ratio of 0.71 ± 0.04. At 1,020 W/m², the system produced 1,120 ± 32 W of DC power, a dynamic head of 16.2 ± 0.9 m, a discharge of 5.20 ± 0.24 L/s and 826.4 W of hydraulic power. Over 10 years, the solar system had a life-cycle cost of $2,070 compared with $4,870 for the petrol pump; LCOE was $0.112/kWh compared with $0.418/kWh and LCOW was $0.024/m³ compared with $0.077/m³. Solar pumping also achieved 96.4% operational reliability and 82.1% irrigation conveyance efficiency. The findings indicate that appropriately sized solar PV pumping systems can provide a technically viable, economically competitive and reliable option for dry-season irrigation in Shani and comparable semi-arid environments.