Offshore Wind Energy Turbines Pose No Threat to Air Navigation and Traffic Operations According to the FAA

The Federal Aviation Administration affirmed its previous decisions that the Cape Wind offshore wind energy project poses no threat to air navigation and traffic operations. This is the fourth time the FAA’s aeronautical study has concluded that the 130 wind-turbine farm would not present a hazard since the project was first reviewed in 2002. The agency must evaluate the project and make a determination every 18 months. This latest determination expires in February 2014.

The same decision was made last year by the FAA; however, the D.C. Circuit Court concluded that the agency had not properly applied its handbook to the project’s evaluation. The court required the agency to go back and analyze whether the project adversely affected visual flight procedures. This latest study showed no adverse effect.

As we discussed in our July 2011 post entitled, “Wind Turbines Effect on Radar Systems and Aviaiton Security,” wind turbines affect the safety of the general and business aviation sector because wind towers may be constructed along routes typically flown by smaller aircrafts. The Cape Cod and Nantucket Sound area, where the Cape Wind project is located, is served by several public use airports, including Barnstable Municipal Airport-Boardman/Polando Field (HYA), Nantucket Memorial Airport (ACK), and Martha’s Vineyard Airport (MVY), as well as one military airport, Falmouth Cape Cod Coast Guard Air Station (FMH). According to the FAA’s determination, the Cape Wind project poses no hazard to flight operations in and out of these airports.

Attention will now turn to the litigation pending in the United States District Court for the District of Columbia (Civil No. 10-cv-01067). In this matter, several community groups and one Native American tribe brought a consolidated action against the U.S. Department of Interior. The action alleges that in approving the Cape Wind project, the agency did not conform to law and perform the due diligence required in evaluating the potential impact the project would have on the environment and the cultural and historical resources of the tribe.

Sullivan & Worcester represents the Conservation Law Foundation, a non-profit environmental group with offices throughout New England, in the matter. CLF is an amicus curiae party supporting the U.S. Department of Interior’s approval of the project.

Positive Cooperation on the Horizon Regarding Wind Turbine Radar Concerns

As mentioned in our July 1, 2011 post entitled “Wind Turbines Effect on Radar Systems and Aviation Security,” the wind energy and aviation security sectors continue to struggle towards common ground, but signs of government agency cooperation with both developers and one another reveal that change is in the works.

The Federal Aviation Administration certainly has its eye on aviation safety and security concerns, as wind turbines may impact radar dependant air traffic and often fall within FAA jurisdiction over construction projects proximate to an airfield or over 200 feet tall. To help ease concerns, FAA has even mandated contribution to radar development efforts as a condition for siting approval. Similar worries have been voiced by the National Oceanic and Atmospheric Administration pointing out that wind turbines often disrupt registration of weather events, such as areas of high precipitation, causing potentially dangerous forecasting and weather tracking obscurities.

Wind energy industry developers understand the agencies’ concerns. To put the technological issue with wind turbine interference in perspective, the technical director with Raytheon explains that “a wind turbine can look like a 747 on final approach” and they “don’t want to have the software eliminate a real 747,” which is a difficult hurdle to surmount. As a result, this issue will remain contentious for both the commercial and business aircraft industries until these concerns are addressed.

United States defense and military agencies maintain that wherever there is a threat and concern caused by radar interference, this concern trumps the push to erect wind energy farms. The Department of Defense has been accused of “foot-dragging” after missing two deadlines pertaining to the impact of wind farming on military operations, and has been criticized regarding the last minute blockage of a Caithness Energy project in Shepherds Flat, Oregon after the company had the project vetted by the Air Force years earlier. Although this project is now on track to becoming the world’s largest wind energy farm, the skein of bureaucracy has been a subject of criticism.  In response, the Department of Defense has changed course and begun to develop a timely, transparent review process through the DOD Energy Siting Clearinghouse, a “one-stop shop” within the DOD for developers and other government agencies.

A current and unique case to watch is that of prospective offshore wind farms on Virginia’s Outer Continental Shelf. Recently, the Virginia Offshore Wind Coalition was pleased to receive results from a Department of Defense assessment identifying 18 of 25 proposed optimum wind harnessing tracts as “compatible with military needs and rules so long as certain [unspecified] guidelines are met.” These wind corridors were of particular importance to the Department of Defense due to both the Norfolk Naval Station, the world’s largest naval base, and a NASA launch facility being in the vicinity. With multiple bids on the table from both turbine farm and energy transmission developers, many are hopeful that the lengthy review process might be nearing its end.

As this issue progresses please check back to this blog for future posts.


Special thanks to Sullivan and Worcester’s Alex Kellenberg, environmental intern, for preparing this post.

Wind Turbines Effect on Radar Systems and Aviation Security

Special thanks to Sullivan & Worcester's Ari Hoffman, environmental intern, for assisting in the preparation of this post.

On June 28 and 29 in Ottawa, the Canadian Wind Energy Association (“CanWEA”) in collaboration with the American Wind Energy Association (“AWEA”) hosted the International Wind and Radar Forum. The Forum was designed to “further the relationship between key regulatory and industry players, while promoting an international dialogue about responsible, effective tools designed to identify and address any potential conflicts between wind energy and radar.” 

Tension between ensuring aviation security and expanding wind energy has arisen due to a wind turbine’s potential to interfere with the radio frequency waves emitted by radar systems. Wind turbines can defeat radar, especially when grouped into large wind farms, either by creating unwanted reflections or by blocking signals which can result in clutter on radar maps. Radar clutter prevents aircraft and surface air traffic controllers from determining the location, range, altitude, direction and speed of nearby objects, posing a safety threat. 

Due to concern over aviation security, the British Wind Energy Association (“BWEA”) estimates that there is 4.7 gigawatts of wind energy on hold in Britain and AWEA estimates that in the United States over 9.0 gigawatts of wind energy are on hold. These statistics are worrisome to the United States Department of Energy, which relies heavily on the use of wind energy to help reach the nation’s renewable energy targets.

A myriad of solutions to this problem have emerged. Earlier this year, the United States Department of Homeland Security awarded a $22 million contract to Raytheon, a leader in this field, to study how proposed wind farms would interact with existing radar systems. CASSADIAN, the defense and security division of EADS, developed a solution based on modifications to the radar antenna as well as signal processing. Further, SCANTA 4002 Radar, a system developed by Terma, is designed to separate smaller air objects from larger surface objects, such as wind turbines. This radar can be independently installed and integrated with existing radar installations. 

While some solutions try to change radar systems, Vestas is working to change wind turbine blades into radar-friendly stealth blades. Vestas believes the solution lies in coating blades with similar material used to produce stealth planes which are invisible to radar. Vestas announced on June 29, 2011 that the use of “stealthy” blades reduce radar clutter by around 99% or 20 decibels (The Guardian UK).

As wind energy expands, radar and blade technologies to avoid disturbances will become even more vital, especially to smaller aircraft that may fly along less traveled routes where large wind turbine farm development is more likely. As this issue progresses, please check back to this blog for future posts.