"What we're really doing is testing the technology to see what kind of application it would have for Duke Energy," said Duke spokesman Randy Wheeless. "Right now we're finding that surveying transmission lines and looking at the panels on a solar farm can make repairs cheaper and faster."
Drones could also improve Duke's response to storms and other outages.
"A drone would be able to look and tally up how many poles we need and what kind of wire we need," Wheeless said. "That way we could make repairs quicker, rather than have someone go there by foot or in a helicopter."
Duke received an exemption from the FAA to fly the aerial vehicles in June.
About a dozen utility or service companies have sought permission to use drones for similar purposes. Xcel Energy has recently used drones to review three power plants in Colorado and Minnesota, and Southern Co. is testing the use of drones in Georgia, according to The Associated Press.
AeroVironment has a blanket permit from the FAA to fly drones up to 200 feet, but the company must give FAA a few days' notice if it plans to fly close to airports or power plants, said Eric Haney of AeroVironment.
The fixed-wing aircraft ranges from 13 to 15.5 pounds and takes off from an incline ramp. At a demonstration Wednesday, the drone's engine emitted a high-pitched sound that could be heard several hundred feet away.
The quadcopter, which is a drone with four propellers, weighs a little more than 5 pounds and takes off vertically. In contrast with the fixed-wing drone, the quadcopter is very quiet and couldn't be heard while it hovered over the solar panels it was inspecting.
The fixed-wing aircraft has a greater range than the quadcopter and can fly for up to 31/2 hours, while the quadcopter averages a flight time around 40 minutes.
Before flying the aircraft, the team from AeroVironment sets a flight path using GPS plot points. If the aircraft loses its GPS signal, the drone automatically returns to its original launch point.
It collects infrared images and can carry other types of cameras.
Some have voiced concerns. The Air Line Pilots Association International, a labor union, said drone pilots should be licensed for commercial flights like its members, a higher standard than the government required of Southern Co. The National Agricultural Aviation Association says the drones should be better-equipped to avoid collision with low-flying crop dusters and other aircraft, according to AP.
The company won't fly the aircraft if the wind speed exceeds 25 knots, according to Haney.
"We're looking at three things: how safely the flights are compared to what we do today, what is the operational efficiency, and is there a business case," said Aleksander Vukojevic of Duke.
Vukojevic addressed safety concerns by explaining that the drones will never fly completely over power lines and that their wingspan isn't long enough to cause line-to-line accidents.
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