Owls in ca-hoots with science in bid to create silent wind turbines

A new material that could make wind turbines and even aircraft quieter by mimicking the design of owls’ wings that allows them to silently hunt their prey has been developed by scientists. The Cambridge University-led team studied the feathers of the stealthy nocturnal airborne predators to produce the coating, due to be unveiled at a US conference. Because of the noise they make, wind turbines are often braked to make them turn more slowly and quietly, but the team behind the new material say that it could enable the machines to turn faster and boost their output without increasing noise as a side-effect.

Many owls - primarily large owls like barn owls or great grey owls - can hunt by stealth, swooping down and capturing their prey undetected. While we’ve known this for centuries, what hasn’t been known is how or why owls are able to fly in silence.

Professor Nigel Peake of Cambridge’s department of applied mathematics and theoretical physics.

The team, which also included scientists from Virginia Tech, Pennsylvania’s Lehigh and Florida Atlantic universities, said they used powerful microscopes to look at owl wings. They found that they have a “downy covering” to their flight feathers, plus bristles on their on the leading of their wings and an “elastic fringe” on the trailing edges. The discovery enabled the team to make a 3D printed plastic cover for a wind turbine, which reduced the noise it generated in wind tunnel tests by 10 decibels. They believe it can be adapted for other types of wings and blades and want to move on to improve the coating further and test it on a working turbine.

Science