|
Separating airplanes from wind turbines People planning the Fire Island wind farm offshore Anchorage continue to work with the FAA to avoid air traffic control conflicts Alan Bailey Petroleum News
Passenger jet pilots flying into Ted Stevens Anchorage International Airport are familiar with turning above Fire Island, in Cook Inlet just offshore the airport, as they position themselves for final approach. But the proposal to build a wind farm on Fire Island in close proximity to the airport has resulted in some tricky issues in designing the wind facility.
After extensive discussions with the Federal Aviation Administration, the Fire Island project is moving forward, with the start of construction slated for summer 2009 and erection of the wind turbines planned for 2010. And on Jan. 29 Ethan Schutt of Cook Inlet Region Inc. told the International Association for Energy Economics Alaska Chapter about the project status and about the ways in which the FAA concerns are being addressed. CIRI is the major landowner on Fire Island and has partnered with EnXco to build the wind farm.
The wind turbines will be located in the southern part of the island, away from the flight path into the airport, Schutt said.
How many turbines? The FAA has currently permitted 20 feasible wind turbine sites for the project but, although the project is proceeding on that basis, the project partners would prefer the economies of scale that could be achieved with more turbines.
“The layout and the design that we would like to have and are working very hard to get to is for 36 turbines, which would be a much better deal for everyone involved and including ultimately the ratepayers,” Schutt said.
Each turbine will be able to generate 1.5 megawatts of electrical power. So increasing the number of turbines would expand the output of the wind farm from 30 megawatts to 54 megawatts, spread across somewhat similar fixed project costs.
The project partners also hope to persuade the FAA to relax a height restriction that the agency has imposed on the turbines.
The FAA permitted the turbine blade hub heights to be 65 meters, whereas the standard for the machines that the wind farm will use is 80 meters. Using the standard height would increase the power output of the machines.
“There is a substantial difference in the efficiency of the wind capture from 65 to 80 (meters), and there is not a substantial difference in the cost of your installed capital equipment,” Schutt said.
Radar and VOR equipment One of the biggest hurdles that the project had to address was ensuring that the wind farm would not interfere with the air traffic control radar for the airport, Schutt said.
“That has been resolved,” he said.
However, there is a remaining issue with the FAA’s VHF omni-directional radio, or VOR, navigation beacon on the island.
“It’s old navigation technology but it’s still critical for the FAA flight operations at the airport,” Schutt said.
The FAA wants the wind farm project to bear the $2 million cost of upgrading the beacon to technology that can accommodate the presence of the turbines.
“We’re attempting to work with the FAA to build them a replacement VOR somewhere on the airport property with the upgraded technology,” Schutt said. “… We believe we could easily build an entirely new system for them and probably do it at about half the cost and in about half the time.”
| 