Windbreaks could help wind farms increase energy production

Windbreaks may seem like a counterintuitive idea to increase the performance of a wind turbine. But physicists report that low wind-blocking walls could actually help wind farms produce more power.

Scientists already knew that output from a single wind turbine could be improved with a windbreak; While windbreaks slow the wind near the ground, above the height of the windbreak, wind speeds actually increase as air rushes over the top. For large wind farms, there is a drawback, the wake of a windbreak slows the flow of air as it travels farther through the rows of turbines, which might suggest that windbreaks would be a wash for wind farms with many turbines.

But by striking a balance between these competing effects, windbreaks placed in front of each turbine can increase power production, new computer simulations suggest. It all comes down to windbreak dimensions, wide, squat barriers are the way to go, according to a simulated wind farm with six rows of turbines. To optimize performance, windbreaks should be one-tenth the height of the turbine and at least five times the width of the blades, the physicists report. Such an arrangement could increase overall power by about 10 percent, the researchers found. That’s the equivalent of adding one additional turbine, on average, for every 10 at a wind farm.

The technique could be useful in places where the wind tends to blow in one direction, such as coastal regions. Future studies could investigate how this technique could be applied in places where the wind direction varies.