Wind Turbines Can Disrupt Radar

First posted on 07-20-2010

Studies have shown that wind turbines can be fatal to bats that fly near them. It isn’t contact with the whirling blades that proves harmful to bats, it’s the air pressure change created by the blades that causes damage to their lungs. Now, as wind farms begin to grow in response to a need to discover alternative energy sources, a new problem is beginning to surface.

Turbines can “erase” aircraft from radar screens and produce echoes that falsely signal the onset of a thunderstorm.

Blades rotate at speeds of up to 200 miles per hour, enough to play havoc with whether radar signals reach their targets, or echoes return from them. The resulting clutter produces shadows that conceal planes.

While no major incidents have been reported, the industry and the Federal Aviation Administration (FAA) are working to resolve the problem before an accident occurs.

Dorothy Robyn, a deputy Defense Department undersecretary, called the issue “serious but solvable” at a congressional hearing.

Current solutions include providing more training for radar operators, upgrading radar systems and changing how wind farms are designed. At least one company is working to coat the blades with something similar to what is used on stealth bombers in an effort to make the blades invisible to radar.

The FAA holds jurisdiction over all structures 200 feet high or more. Wind turbines, stretching 200 to 400 feet tall, fall into that category, and require FAA approval before being constructed. As more turbines begin to dot the landscape, the volume of proposals submitted has grown rapidly. In 2004, only 3,030 wind turbine cases were reviewed by the FAA. By 2009, that number grew to 25,618 and through half of this year, the number stood at 18,685 cases.

Although exact numbers have not been compiled, the amount of wind turbine related concerns has also risen during that time.

Share | |