Analytical Evaluation of Energy Harvesting Techniques for Wireless Sensor Networks in Agricultural IoT Applications in Kano State

Wireless sensor networks for agricultural monitoring require long operational lifetimes with minimal maintenance intervention in field environments, making energy harvesting from ambient sources an analytically important design consideration for deployment in Nigeria's major agricultural zones. This study analytically evaluates solar photovoltaic, piezoelectric vibration, and radiofrequency energy harvesting techniques for powering wireless sensor network nodes in agricultural IoT deployments in Kano State, North West Nigeria. A combined analytical and measurement study was conducted, with ambient energy source characterization measurements collected at three representative agricultural sites across the Kano River Irrigation Project area over six weeks. Solar irradiance, wind-induced vibration spectra on irrigation pipes, and ambient RF power density from nearby base stations were measured and used to parameterize analytical energy harvesting models. Energy balance analyses were performed for three sensor node duty cycle configurations representing soil moisture, microclimate, and crop health monitoring applications. Solar photovoltaic harvesting demonstrated the highest average power output of 18.4 milliwatts per square centimeter of panel area under Kano's high irradiance conditions, sufficient to sustain all three sensor node types with appropriate energy storage buffering. Piezoelectric harvesting from irrigation pipe vibration provided a viable supplemental source averaging 0.8 milliwatts during irrigation cycles. RF harvesting was viable only within 200 meters of a base station, limiting its applicability to near-perimeter farm sections. The study provides analytically derived energy harvesting system specifications for IoT agricultural deployments in northern Nigerian field conditions. Keywords: energy harvesting, wireless sensor network, agricultural IoT, solar, Kano State.