He declines to speculate on whether the findings will prove good or bad for wind power but hints that improvements in the Air Force's handling of permit applications is on the way. The Federal Aviation Administration (FAA) does not allow any wind projects to be built within 20 miles of a radar system without an intense in-depth review. "We feel our own internal process has matured enough that we should be able to get a more predictable process out to folks and that's something we're working with the Department of Energy and the FAA on," he says.
One major problem is that only the landowner of a potential wind plant site may lodge a request for assessment of potential interference to radar. That puts project developers at risk of buying or leasing land, only to have the FAA refuse a construction permit. Sample says the Air Force is trying to change that.
"One of the things we're definitely trying to work on is to make sure that the evaluation process is transparent and predictable for the wind developer. Right now it hasn't always been so," admits Sample. "We work through the FAA process but if people want to talk to us a little early that's what we're trying to work on."
Wind turbines can diminish the performance of nearby radar systems by altering the images normally presented to radar operators. Similar findings in the UK have prompted concerns and delays in some project development. But software solutions for radar systems have been identified as an effective solution.
The US Air Force study used the King Mountain wind farm in Texas, which was constructed before the 20 mile regulation came into force and lies within that range of an FAA long range radar.