This is an excerpt from the First Quarter 2013 edition of the Wind Program R&D Newsletter.

The U.S. Department of Energy (DOE) and federal agency partners recently completed the final operational field test in a 2-year initiative to accelerate the deployment of the most promising new technologies for mitigating radar interference caused by the physical and electromagnetic effects of wind turbines. These new mitigation technologies are expected to open up new areas to wind developers that have been deferred, delayed, or cancelled because of wind turbine interference with radar systems.

Since 2000, wind generation capacity in the United States has increased from 5 GW to 60 GW and could grow to as much as 305 GW, or 20% of the nation's electricity by 2030. To accommodate future wind energy growth in the United States, new technologies are needed to mitigate interference impacts from wind turbines on radar systems, which include decreased sensitivity, false targets, and corrupted track quality.

The test team orchestrating the Interagency Field Test and Evaluation of Wind-Radar Mitigation Technologies has completed flight operations associated with an $8 million demonstration initiative co-funded by DOE, the U.S. Department of Defense (DOD), the Department of Homeland Security (DHS), and the Department of Transportation's Federal Aviation Administration (FAA). The goals of the initiative are to characterize the impact of wind turbines on current air surveillance radars, assess new technologies for near-term mitigation, and gain a better understanding of the radar-wind interaction issues to enable the development of long-term mitigation strategies.

Two national laboratories, Sandia National Laboratories (a DOE research facility) and the Massachusetts Institute of Technology Lincoln Laboratory (a DOD research facility), managed the tests and evaluated resulting data from three flight campaigns to establish baseline capabilities for three national airspace radar systems and test eight mitigation technologies on short- and long-range (60 and 250 nautical miles) radar systems. The FAA provided extensive support in managing the flight operations and air traffic control as well as technical support for long-range radar systems. The DOD also provided technical support for radar and DOD, DHS, DOE, and the National Oceanic and Atmospheric Administration provided critical test program aircraft, flight tracking, and air operations.

The three test campaigns used a variety of aircraft types flown across a range of speeds near radar sites with high concentrations of wind turbines in Tyler, Minnesota; Abilene, Texas; and King Mountain, Texas. Wind farm owners also provided data obtained with supervisory control and data acquisition systems, including wind speed and rotor rotation rate from their wind turbines in and around the test area. These data, when combined with radar and flight data, enabled the laboratories to characterize the effects of wind turbine interference and predict effects on similar radar systems in other locations with a much higher level of confidence.

Multiple agencies rely on radar systems to protect the nation, and this interagency field test and demonstration effort is proving to be vital for the acceptance of new wind turbine radar mitigation technologies. The laboratories' technical evaluation of the most promising technologies will be used by FAA to validate and accelerate the new mitigation technologies for temporary deployment into the national aviation system. In addition, the agencies are developing a longer-term plan involving more permanent solutions that can be applied to both land-based and offshore wind turbines.