The Nation's use of wind turbine “farms” to generate electricity has been growing dramatically in recent years and more growth in the number of farms is expected. As of mid 2006 over 7000 applications to build wind turbines have been received, more than the 4000 received in all of 2005. These wind farms can have over 100 towers and turbine blades over 200 feet in length and the tips of the blades exceeding a height near 400 feet above ground level.

Experience has demonstrated that when wind farms are located “close” to Weather Surveillance Radar-1988, Doppler (WSR-88D) systems the towers and the “exhaust” from wind turbines can impact radar data quality and the performance of radar algorithms. The wind farms in operation were installed without apparent consideration to their impact on weather radars. The federal government is developing policy regarding siting wind energy farms near radars. Thus far, federal policy has been addressing the impact of wind farms on point-to-point communications and air traffic surveillance radars. The Radar Operations Center on behalf of the Next Generation Weather Radar (NEXRAD Program) is working with other federal agencies to adopt a policy that also address the impacts of wind farms on weather surveillance radars while encouraging wind farm development at locations where radars and wind farms can co-exist with minimal interference.

This paper and presentation will provide examples of the impact of wind farms on WSR-88D base data and products; background on the dramatic growth in the number of wind farms and their characteristics; methods available to mitigate impacts to radar data quality; and status of federal policy regarding the siting of wind farms.