Leaf-inspired rain-energy harvesting device
Phys. Rev. Applied 25, 034049 – Published 16 March, 2026
DOI: https://doi.org/10.1103/h1ht-1xqf
Abstract
We study a rain-powered energy-harvesting device inspired by the natural impact of raindrops on leaves. In nature, a raindrop striking a leaf at high speed causes it to deform and vibrate. Inspired by this dynamic response, our device uses an elastic beam coupled to a piezoelectric material to convert mechanical vibrations from droplet impacts into electrical energy. We conduct experiments to analyze how beam length, droplet impact location, and residual droplet mass affect energy conversion. Our results, supported by a theoretical model, show strong agreement when the beam length exceeds 5 cm. Beyond this length, the energy conversion becomes independent of further increases, suggesting that 5 cm is optimal for maximizing output. To validate practical applicability, we also test the device under real rain conditions, demonstrating consistent performance. Understanding the interplay between raindrop dynamics and energy conversion can guide the design of efficient, scalable rain-powered energy-harvesting systems for environmental applications.
