Purpose <p>The aim of this work is to develop and evaluate a galloping-based piezoelectric energy harvester (GPEH) designed to operate efficiently at low wind velocities. The study investigates the influence of the streamwise dimension of a rectangular bluff body on the harvested power, with the goal of enhancing energy harvesting performance in low-velocity wind environments.</p> Methods <p>A cantilever-type energy harvester equipped with a rectangular bluff body was studied for wind velocities ranging from 0.6 to 1.5 m/s. Both numerical and experimental approaches were employed. Computational Fluid Dynamics (CFD) simulations were carried out using ANSYS-CFX to analyze the flow behavior and galloping response around bluff bodies with different streamwise dimensions. Additionally, wind tunnel experiments were conducted in an open-circuit suck-down wind tunnel to measure the output power generated by the energy harvester under controlled conditions.</p> Results <p>The experimental results demonstrate that the GPEH with a bluff body streamwise dimension of 5 cm produces a maximum output power of 0.14 mW, which is 48% higher compared to the output when the streamwise dimension is 1 cm. The results confirm the significant effect of bluff body geometry on power generation at low wind speeds.</p> Results <p>The study successfully demonstrates a proof of concept for galloping-based energy harvesting applicable to flexible structures subjected to flow-induced vibrations, highlighting its potential for low-velocity wind energy harvesting applications.</p>