Donut-Shaped Plastic Improves Wind Turbine Output By Up To 30%  

Ecogeek has a post on a technique that apparently allows wind turbine output to be boosted by funneling wind onto the blades - Donut-Shaped Plastic Improves Turbine Output By 30% .

Leviathan Energy has come up with a way to improve wind turbine efficiency that has nothing to do with the size or angle of the blades. The company's Wind Energizer is instead a donut-shaped structure made of plastic and steel that wraps around the base of the turbine to maximize wind velocity.

The Wind Energizer can be customized to any size turbine. The shape and size of the structure depends on the turbines height, blade length, wind direction and strength. Once all those aspects are factored in, Leviathan constructs the Wind Energizer to funnel the wind flow so that the highest velocities hit the blades.

The initial tests have shown a 20-40 percent increase in output compared to control turbines. At lower wind speeds, the Wind Energizer has an even greater effect, increasing output by as much as 150 percent.

The company estimates that the Wind Energizer pays for itself in about four to five years in increased performance and that maintenance costs will decrease for users as well because the structure balances the wind load on the turbine.

So far the product has only been tested on smaller-scale turbines, so further testing will need to be done to determine the exact results for larger turbines.