From lighting homes to energizing major factories, the region’s electric transmission system powers our economy and virtually all aspects of daily life.
National Grid owns and operates approximately 3,000 miles of electric transmission lines in Massachusetts, Rhode Island, New Hampshire and Vermont, and works hard to maintain the reliability of this system that serves National Grid’s 1.7 million New England electric customers, plus more than 60 other interconnected electric utilities and power producers.
Over the next several weeks, National Grid will conduct helicopter patrols of its entire New England transmission network to identify any potential problems so they can be addressed by National Grid transmission line crews before they impact service for customers. These aerial patrols, conducted semi-annually, complement ground-level inspections by quickly and efficiently covering large swaths of the transmission system, especially across rugged and isolated terrain.
“Customers depend on the transmission system 24/7 to connect them to the power they need, so we take great care to keep the system operating safely and reliably, said Fred Raymond, National Grid vice president, Electric Project Management and Complex Construction. “The helicopter patrols are an important component of our overall inspection and maintenance program because they give us a birds-eye view of the system.”
Two types of helicopter inspections are conducted. Infrared inspections detect any excess heat emanating from electrical connectors and components that may indicate wear, corrosion, or fatigue.
Visual inspections are also performed by experienced personnel using high-power gyroscopic binoculars to pinpoint any signs of wear on power lines and lightning protection devices; damaged or leaning transmission structures; loose or broken guy wires; broken, chipped or cracked insulator equipment; and trees leaning toward the lines or into the transmission corridors.
The inspectors also look for signs of waste disposal or unauthorized construction on transmission corridors. These could alter the clearance between the ground and the power lines and might lead to human contact with the lines that could result in severe injuries, or vegetation interference that could lead to power outages. Inspectors will also look for signs of ground erosion, which may cause the transmission structures to become unstable.
National Grid notifies all appropriate local, state and federal agencies such as the Department of Homeland Security, and state and local police that the patrols will be taking place. Flight schedules and routes may be changed on short notice due to regional weather conditions.