Humpback Whales Solve a Big Problem for Wind Turbines

**Wind Turbines from flippers of Humpback whales**

What do humpback whales and a wind turbine have in common? Scalloped blade edges.

Learning from whales to create efficient wind power

IMAGINE YOU’RE DRIVING your car on a clear day. You idly stick your hand out of the window, and tilt your hand, playing airplane as the wind pushes your hand upwards.

That’s a lift—the same lift that allows an airplane to stay aloft or a windmill blade to turn. To help these man-made technologies increase maneuverability in the air, scientists took a tip from one of the lift experts of the ocean: the humpback whale.

The bumpy protrusions, known as tubercles, on the leading edge of humpback whale flippers have already inspired more efficient wind turbine blades that are able to produce more power at lower speeds.

Turbine aerodynamic performance has been significantly improved and noise reduced thanks to the tubercle technology developed by biologist Frank Fish, aeronautical engineer Philip Watts and film-maker, inventor, and entrepreneur Stephen W. Dewar. This team achieved its breakthrough after Fish discovered tubercles.

Wind tunnel tests of model humpback fins with and without tubercles have demonstrated the aerodynamic improvements tubercles make, such as an 8% improvement in lift and 32% reduction in drag, as well as allowing for a 40% increase in the angle of attack over smooth flippers before stalling. Fish is applying the lessons learned from humpback whales to the design of wind turbines to increase their efficiency.

What Can a Humpback Whale Teach a Wind Turbine? | Think Like a Tree

Affixing tubercles to blades has shown similar effects with windmills, fans, surfboard fins, and even a hydroplane. “Because you can go to a higher angle of attack, there’s an increase in the amount of lift that can be generated,” says Fish. That’s especially important for wind turbines: Gusts from two different directions can stall the blade of a windmill, to the point where it’ll actually blow up.

“You have to engineer windmills at fairly low angles of attack, so you aren’t getting that much lift and energy in the process,” says Fish. With tubercles, engineers can design windmills with a higher angle, enabling them to get more lift, spin faster, and gather more energy—while (mostly) safely assured that they won’t blow up.

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