A High-Adaptability Ambient Energy Harvester Enhanced by the Canyon Effect for Smart Agriculture

Abstract

Ambient energy harvesters show great potential for powering distributed sensor nodes. However, their output performance is often limited by a single-source energy, resulting in poor adaptability, stability, and energy utilization ratio in variable weather conditions. Herein, a high-adaptability ambient energy harvester enhanced by a bi-concave flow amplifier is proposed. The omnidirectional airflow smoothing enhancement design of the amplifier is inspired by the canyon effect. And the inclined surface of the amplifier offers building-block-like modular assembly, enabling synergistic non-invasive integration of electromagnetic-photovoltaic-triboelectric effect. The results indicate that the amplifier boosts the wind energy harvesting efficiency by 86.87 % and reduces the start-up wind speed to 0.4 m/s. Within the theoretical-simulationexperimental framework, the measured power densities reach 14.158 W/m 2 (wind), 63.47 W/m 2 (solar), and 25.42 W/m 2 (raindrop), demonstrating robust performance across varying weather conditions. Notably, leveraging the multi-energy sensing capabilities of the harvester, a self-powered weather warning system and an automated smart greenhouse control system have been developed. This system-level application offers a new perspective for the deep integration of energy harvesters with smart agriculture.