ENERGY HARVESTING TECHNIQUES FOR LOW-POWER IOT DEVICES

Abstract

The pervasive deployment of Internet of Things (IoT) devices—spanning smart cities, environmental monitoring, industrial automation, and healthcare—poses formidable challenges for sustainable power supply. Traditional battery dependency restricts lifespan, increases maintenance, and contributes to environmental burdens. Energy harvesting (EH)—the capture and conversion of ambient energy into usable electrical power—offers an attractive alternative to extend operational autonomy of low-power IoT devices. This comprehensive study reviews state-of-the-art EH techniques including photovoltaic (solar), thermoelectric, piezoelectric, radio frequency (RF), triboelectric, and hybrid systems; presents a methodology for cross-comparative evaluation; analyzes integration challenges such as energy intermittency and storage; and demonstrates prototype performance metrics. Results indicate that multi-source hybrid harvesters coupled with advanced power management offer the most resilient and high-efficiency solutions for battery-less or battery-assisted IoT nodes. Key implications for ultra-low-power circuit design, reliability, and future research directions—such as nanogenerators and integrated power path management—are discussed.