Whale-Inspired Wind Turbines

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Already, attempts are being made to incorporate the tubercle design into commercial products. Fish is president of a venture based in Toronto, Ontario, called WhalePower, which has begun demonstrating the advantages of tubercles when they're integrated into the leading edges of wind-turbine and fan blades.

Prototypes of wind-turbine blades (see image below) have shown that the delayed stall doubles the performance of the turbines at wind speeds of about 17 miles per hour and allows the turbine to capture more energy out of lower-speed winds. For example, the turbines generate the same amount of power at 10 miles per hour that conventional turbines generate at 17 miles per hour. The tubercles effectively channel the air flow across the blades and create swirling vortices that enhance lift.

WhalePower, based in Toronto, Ontario, is testing this wind-turbine blade at a wind-testing facility in Prince Edward Island. The bumps, or "tubercles," on the blade's leading edge reduce noise, increase its stability, and enable it to capture more energy from the wind.
Credit: WhalePower

Stephen Dewar, director of research and development at WhalePower, says that ongoing tests at the Wind Energy Institute of Canada, in the province of Prince Edward Island, have shown the tubercle-lined blades to be more stable, quiet, and durable than conventional blades. "The turbine has survived being hit by the edge of a hurricane, and it survived wind-driven snow and ice," he says.

WhalePower has also shown in demonstrations that tubercle-lined blades on industrial ceiling fans can operate 20 percent more efficiently than conventional blades can, and they do a better job at circulating air flow in a building. The results were dramatic enough to convince Canada's largest maker of ventilation fans to license the design, which will appear in a new line of products scheduled for release at the end of April.

"This licensing agreement with the fan company is great," says Fish. "It basically shows one of the many potential applications for this technology. The union of biology and engineering through biomimetics will make future innovations possible."

The Harvard study reaches the same conclusion. "It is possible that the lessons learned from humpback-whale flippers will soon find their way into the design of special-purpose wings, hydrofoils, as well as wind turbine and helicopter blades."