Design and laboratory testing of a hybrid renewable energy system using commercial off-the-shelf components

This study explores the design and performance evaluation of a solar-wind-battery hybrid energy system intended for remote, high-altitude, unmanned locations. The system addresses the challenges of power reliability in areas with unpredictable renewable energy availability, aiming to support surveillance and communication equipment with continuous 10 W power demand. The setup incorporates vertical axis wind turbines (VAWT), photovoltaic (PV) panels, and a battery bank, optimized for autonomously sustainable operations under extreme environmental conditions. Additionally, provision was made to connect to an AC power source (Diesel Generator) has also been provided. Battery sizing was guided by energy demands over 3–4 autonomous days, with lithium iron phosphate (LFP) selected for its high cycle life, safety, and reduced environmental impact. Battery sizing calculations yielded a required capacity of 2400 Wh. Experimental trials confirmed that the system could sustain a 10 W load for 24 h with minimal discharge (~ 0.7 V drop) and showed stable thermal behaviour (temperature rise from 26 °C to 27.3 °C). Under accelerated 2000 W load testing, the battery discharged completely in 75 min, with temperature rising to 30.2 °C. Charging via AC source took 4 h and 30 min to raise voltage from 21.8 V to 27.5 V, while charging via hybrid renewable inputs required 33 h. Hybrid operation enabled seamless source-switching based on battery state of charge and availability of inputs, maintaining thermal limits below 49 °C. These results validate the system’s robustness and suitability for energy-resilient, off-grid applications in extreme environments.