New Siemens Low-Noise Wind Turbine Inspired By Flight Of The Owls

Siemens unveiled a new raft of wind turbine designs this week at the WindEnergy Hamburg trade show, including a low-noise wind turbine which the company explains was inspired by the silent flight of the owl.

Announced on Wednesday, Siemens unveiled the SWT-3.3-130LN wind turbine, which operates at a reduced rotor speed and includes aerodynamic addons to its rotor blades which mean the turbine can be operated at a noise level of only 104.9 decibels. Siemens not only made aeroacoustic optimisations to the blades which improve silent operation, but Siemens also designed the trailing edges of the blades to be equipped with a combination of serrations and combs, which Siemens has labelled DinoTail Next Generation.

It is these serrations and combs that Siemens proudly says were inspired by the trailing edge fringe of an owl’s wing, which provide silent flight for the nocturnal predator. Specifically, the specific makeup of an owl’s wings have a “serrated, fringed structure at the trailing edge, and small combs at the leading edge of the wings,” which “are believed to mitigate the noise of the air flow by generating fine vortices.”

“In our wind tunnel measurements and field tests, the combed teeth showed a substantial reduction in wind turbine noise at all wind speeds,” explained Stefan Oerlemans, Key Expert, Aeroacoustics, at the technology department of Siemens Wind Power. “This structure that was inspired by owl wings does not compromise the aerodynamic performance.”

Importantly, the modifications to minimize the wind turbine decibel level has not impacted the annual energy production of Siemens’ wind turbines, which means that sites requiring low noise can have their cake and eat it too.