A simple, scalable flutter-driven wind energy harvester

When we think about renewable energy, images of sprawling solar farms or towering coastal wind turbines usually come to mind. Yet, there is a quieter, more compact option: a slender strip of material fluttering in the breeze, capable of converting ambient airflow into usable electrical energy.

In our research group, we have been exploring how flexible structures—thin polymer sheets—can convert the energy of ambient flow into electricity using piezoelectric materials. These materials generate an electrical signal when mechanically deformed. Think of them as energy translators—converting flutter and vibration into voltage.

Our work focuses on a simple idea: attach a flexible plate with a piezoelectric sheet to the downstream side of a cylinder and expose it to wind. As wind flows past the cylinder, it causes the attached plate to flutter—much like a flag.

Our study has been published in Physics of Fluids.

What is particularly interesting is the dynamic behavior of the system. At low velocities, the plate experiences weak, aperiodic motion. But as wind speed increases, the system enters a lock-in regime—a resonance phenomenon where the oscillation frequency of the plate synchronizes with the frequency of vortex shedding. In this regime, we observe high-amplitude, periodic oscillations that dramatically increase the strain on the piezoelectric material and, consequently, the electrical output.

For perspective, many earlier devices in the same category reported only a few microwatts of power at similar wind speeds. By refining the plate’s thickness, length, and flexibility, and precisely matching the electrical resistance in the circuit, we managed to scale the power output by two to three orders of magnitude.

To validate real-world feasibility, we constructed a rectifier and storage circuit and demonstrated that the harvested power could drive up to 20 LEDs continuously. Even 40 LEDs could be momentarily lit using stored charge. These results suggest clear potential for self-powered low-energy devices, such as environmental sensors or wireless nodes in remote or hard-to-reach areas. That said, important challenges remain—particularly in improving energy conversion efficiency and optimizing the design for practical integration.

What excites us most is the simplicity and scalability of this approach. Unlike traditional turbines, these harvesters have no rotating parts, minimal maintenance needs, and can be easily integrated into urban or natural environments. As the world seeks smarter, smaller, and cleaner ways to generate energy, this flutter-powered harvester may just have the wind at its back.

This story is part of Science X Dialog, where researchers can report findings from their published research articles. Visit this page for information about Science X Dialog and how to participate.

Shubham Giri and Umesh Kumar Patel are Ph.D. candidates in the Department of Mechanical Engineering at IIT Bombay, India. V. Kartik, Amit Agrawal, and Rajneesh Bhardwaj are faculty members in the same department.