Abstract. Piezoelectric Energy Harvesting (PEH) of uid-ow energy has attracted signi cant attention throughout the last decade. In the previous PEH from uid ow, a piezoelectric beam was placed behind a blu body, such as circular cylinders. Hence, the piezoelectric beam oscillated due to the vortex shedding behind of the blu body. Subsequently, this vibration generated voltage in the beam. In many engineering vehicles such as airplanes, the strong vortex shedding caused by blu body was destructive and reduced the e ciency of devices; therefore; it was not proper to attach a blu body to these devices. In this paper, PEH from vertical beams in low speeds and high-speed ows is investigated. The current work shows that in contrast to low-speed ows, the extracted power from vertical beam in high-speed ows is considerable. Moreover, as a practical example of vertical beam in high-speed ows, the energy harvesting from piezoelectric Gurney ap attached to an NACA2412 airfoil is investigated. Finally, this study proposes a piezoelectric vertical beam with attached end cylinder as an energy harvester in the lowspeed ows. It is indicated that this device has strong vibration and, therefore, produces a remarkable electrical power.