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March 06, 2008

Uprating wind turbine blades and more efficient ceiling fans


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

I have talked frequently about nuclear power uprating (changes in fuel design and other changes that can increase the power generated at existing nuclear power plants. Now there is reports that bumpy wind turbine blades could uprate existing and future wind turbines. The new wind turbine blades come from WhalePower of Toronto, Ontario, Canada. Uprates can be very good, because you spend a lot less to get a lot more out of what is already there.

Prototypes of wind-turbine blades 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 can rapidly develop precise designs for retrofit leading edges or fully integerated tubercle technology blades for any turbine.

-Retrofit blades are stronger than the original unmodified blades.
-Integrated blades meet or exceed all required performance crieria.

They should be commercially available later this year (2008).


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.

8 comments:

Joel said...

This thing looks like someone took a very close up shot of a steak knife.

Snake Oil Baron said...

We could catapult cows into them and get steak faster than ever. Dinner and a show.

It is a fascinating innovation.

bw said...

I believe the serated or bumpy edge is the trailing edge.

If they were used for prop planes then the cow thing might be appropriate. Or think Raiders of the Lost Ark I.

al fin said...

They say the serrated edge is the leading edge. That is what makes it interesting.

Even ceiling fans get 20% better efficiencies. Wind turbines almost double their output. Planes can fly at slower speeds without stalling.

Pretty amazing case of biomimetics.

jim said...

What they say is happening is the bumps in the leading edge break up the air steam into a bunch of little vortices that flow over the air foil much easier.

Al said...

Back in the late 1940’s there was a small amphibious airplane built by Republic Aircraft called a SeeBee. Its wings were unusual in that there were no ribs in the wing; rather the wing was stiffened by having the upper and lower skin corrugated, like tin roofing. The corrugations ran front to back, you would have thought that this would cause a lot more drag on the airplane, but the wing was actually more efficient than a smooth one would be. I never heard of a good explanation of why this was so, maybe there are similar fluid dynamics going on.

csven said...

This reminds me of the recent video showing a bat in a wind tunnel. iirc, the key finding there was also the creation of vortices off of the leading edge.

bw said...

the serrated edge is the leading edge. I did not read it clearly before on that part.