While still relatively new to the energy sector’s toolbox, unmanned aerial systems (UAS), aka drones, are playing an increasingly important role in inspections for Minnesota-based Xcel Energy’s Colorado operations.

Xcel unit Public Service Company of Colorado became the first state utility to operate drones beyond visual line of sight (BVLOS) during a recent inspection of transmission lines near Denver.

Drones have been used for years to conduct remote oil and gas inspections in the onshore and at offshore facilities, as well as by utilities to inspect remote areas after federal aviation regulators began permitting their use.

Xcel CEO Ben Fowke said the company is now “a step closer to fully integrating” UAS aircraft into its daily operations. Drones are helping “revolutionize” utility work by improving “the safety, efficiency and cost-effectiveness of maintaining and protecting the grid” for natural gas and electric operations.

On Wednesday, the Denver-based utility joined local, state and federal government officials in marking milestone BVLOS drone flights to inspect electric power lines near the Fort St. Vrain Generating Station in Platteville using advanced command-and-control technology.

The Federal Aviation Administration (FAA) in a somewhat unprecedented action granted Xcel special permission to conduct the BVLOS under a waiver, which allows the utility to “commercially operate a drone without visual observers or a chase aircraft.”

Xcel’s David Eves, executive vice president for utilities, said the drone development is a natural extension of the company’s “longstanding commitment” to safety for employees, the public and the environment. Drone applications are especially meaningful in Colorado where the mountainous terrain and remote locations make inspection of energy infrastructure even more challenging, he said.

FAA and Xcel have collaborated for several years, with the utility helping to develop operational and safety requirements for UAS operators in the industry. Last year, Xcel and FAA began a safety program partnership to operate drones on power line inspections.

During last year’s wildfires in Northern California, a squadron of drones was launched by Pacific Gas and Electric Co. (PG&E) to gather information on the condition of infrastructure. And at the Williston Basin Petroleum Conference in Bismarck, ND, earlier this year, Harris Corp. outlined a concept for a public-private partnership to develop a Bakken Shale UAS network to inspect oilfields.