Energy-Aware, PV-Driven Smart Irrigation: A Stepwise Implementation and Field Validation in Biskra

This paper presents a reproducible, stepwise implementation and field validation of a photovoltaic (PV)-driven smart irrigation controller that tightly couples soil moisture feedback, low-cost sensing to improve energy and water efficiency in semi-arid agriculture. We document hardware selection, laboratory calibration of FC-28 sensors against volumetric water content (VWC) reference samples (including regression statistics), controller design (bounded proportional law and safety interlocks), and an energy accounting inline power measurement. A field deployment in Biskra (March conditions) demonstrates soil moisture regulation within target bounds while reducing pump electrical consumption by approximately 18 % relative to a fixed speed benchmark. We discuss limitations, sensor drift mitigation, and extensions, predictive scheduling using short term irradiance forecasts and distributed sensing for larger fields.