Here are two types of infrastructure that need a lot of wide open space: wind turbines and airports, and they don't mix. Wind farms haven't been able to be built near airports because traditional radar systems confuse the spinning blades of the wind turbines with aircraft and that confusion could cause a host of problems for air traffic controllers. But that problem may be history with a new radar technology that can tell them apart and opens up more locations for wind farm development.
In the UK, objections from the aviation sector have delayed the building of around 40 wind farm projects that equal about 6GW of clean energy capacity. UK tech firm Aveillant has developed a Holographic Radar system that could potentially get those projects back on track.
“For the most part, airports are lodging planning objections to wind farm development in their vicinity on safety grounds,” Aveillant CEO David Crisp told Gizmag. “A handful of organizations are using blanking technologies, crude techniques to remove the wind farm returns, such as placing the radar behind a hill so that the wind turbines are out of sight. But such techniques are imprecise and leave unmonitored airspace so are not a long term solution to the problem.”
Traditional radar detects aircraft using a rotating antenna that horizontally sweeps a radar beam at regular seconds-long intervals to pick up any objects, but the new Holographic Radar system uses a stationary array that receives radar signals from all directions continuously.
Gizmag reports, "Using those signals, it analyzes what is known as the Doppler phase shift, which relates to how moving objects reflect radio waves depending on their direction and velocity. By doing so, it is reportedly able to easily tell the difference between turbines and airplanes, and can pinpoint any turbines within 20 nautical miles (37 km) of the airport."
Essentially, it's able to tell the difference because, although aircraft and turbines both have spinning parts, one moves position and one does not.
The Holographic Radar technology could be added on to an airport's existing radar system. Once it has learned the location of wind turbines, it can remove those results from the air traffic control screen so that controllers would only see actual aircraft returns.
Aveillant has tested a prototype of the system on a small scale with good results and it plans to test it in full scale at a large wind farm in the near future.