In Situs Efficiency of a Direct Coupled Photovoltaic Irrigation System in Rural Niger, Input Current Oversizing Effect on The Pump Efficiency

A photovoltaic irrigation system, an excellent example of the water-energy-food nexus, is a suitable system for farmers in the semi-arid countries of the Sahel. These systems align with UN Sustainable Development Goals (SDGs), addressing food security, water access, and sustainable energy. However, their efficiency depends on mastering configuration, installation, and operation, crucial for resource conservation and optimal performance. This study evaluates a direct-coupled PVWPS in rural Niger found the PV array was oversized by double. Indeed, exceeding pump manufacturers' specifications by increasing PV array capacity didn't notably improve performance but decreased pump efficiency. For instance, with a 1.5 kWp PV array, the pump flow rate reached 3.5 m3/h. Doubling (100% increase) the PV capacity to 3 kWp marginally increased the maximum flow rate to 4.2 m3/h, yielding only a 20% water flow increase. This underscores the importance of appropriately sizing PV arrays to avoid diminishing returns. These findings are crucial for decision-making in designing and implementing sustainable photovoltaic water pumping systems. Optimizing PV array configuration based on pump specifications can enhance system efficiency and longevity, advancing sustainability goals while conserving resources.