MONITORING OF PHOTOVOLTAIC PANEL IN A SOLAR-POWERED LAB-SCALE SMART IRRIGATION SYSTEM
The solar photovoltaic (PV) or solar panel is an active transducer whose function in the provision of solar energy cannot be overemphasised. Many solar energy systems perform poorly or fail when the properties of the PV and conditions under which they are implemented are not taken into consideration during system design. Others fail due to environmental conditions such as temperature which might degrade the power generated by the solar PV. As a way of ensuring longevity and healthy operation of the PV, there is the need to do a constant monitoring of it properties and generated power. In this work, parameters such as current, voltage, and ambient temperature of 200 W solar panel are measured in real-time and obtained values used in design of solar power for a lab-scale smart irrigation system. The PV power was determined from the measured current and voltage values using appropriate sensors which are connected to an Arduino-based microcontroller. The PV under a load-OFF test was exposed to the sun from 5:30 am to 7:10 pm. The measured solar power confirms the peak sun hour of 4.5 to 5 hours for Ilara Mokin, Ondo State, Nigeria. Load-ON implementation with a lab-scale smart irrigation testbed reveals that irrigation pumps 2 and 3 maintaining an equal distance each from the water source absorb less power compared with pump 1 at a distance more than double of pumps 2 and 3 from the water source. Thus, the distance of the irrigation pumps and sprinklers from the water source is found to play vital role in the pattern of power consumption by the irrigation system. The maximum power thresholds of irrigation pumps under various load-ON conditions were determined. The power thresholds obtained would be useful parameters for configuring the lab-scale smart irrigation controller for effective performance while the peak sun hour obtained is a useful design parameter for this work and implementation of effective solar system in Ilara Mokin and its environs.