The network of power lines that supply electricity to American cities, homes, and businesses are part of what some have called the largest interconnected machine on Earth: the U.S. electrical grid. This machine needs constant tune-ups to stay reliable, and regular inspections are critically important.
As electrical infrastructure inspections can be time-consuming, dangerous, and labor-intensive, some utilities and energy companies are turning to drones to speed up the process. Rodney Murray, one of Skyward’s Professional Services consultants, recently wrote about how drones can be put to use inspecting utility poles. But how else can drones support the power grid?
Here are four key ways drones are improving electrical utility work:
- Reducing some of the risks that technicians face during inspections — like climbing, hiking, or driving to remote assets, flying in helicopters, or entering disaster areas
- Making routine power line patrols easier and faster, enabling more frequent inspections that catch potential problems sooner
- Improving data collection on structures and assets by capturing high-resolution images, thermal sensor data, and even 3D models of assets
- Pulling rope to string new transmission and distribution (T&D) lines over challenging terrain
Using drones to reduce risks and improve power line worker safety
Electrical power line installers and repairers have the 11th most dangerous job in the U.S., according to the Bureau of Labor Statistics. In 2018, power linemen had a fatal injury rate five times the national average rate for all workers.
It’s a dangerous job, but critically important. To keep the electrical grid reliable, the roughly 160,000 miles of high-voltage transmission lines in the U.S. must be inspected regularly. For example, in Oregon, operators must perform routine safety patrols of overhead assets every two years, and detailed inspections every ten years.
This can put workers at risk in the best of circumstances. When crews are sent out to assess outages following a storm or disaster, it gets even dicier. Roads may be snowy, icy, flooded, muddy, or blocked by fire debris.
Drones can often access places where it’s not possible to drive. Drones let crews stay at a safe distance, on the ground, and away from downed wires and teetering trees, while allowing utilities to assess damage.
For example, following an ice storm, Kentucky Power used drones to inspect power lines and check for points of failure. The drone could inspect a line in 20 minutes that would take a ground crew hours or even days to assess given the conditions. With roads treacherous, the drone operation reduced the number of hard-to-reach areas that ground crews needed to access.
Faster and more frequent electrical grid inspections
Increasing the speed — and frequency — of inspections can also help catch issues before they occur. Aging power lines may not hold up to the extremes in weather that come with climate change. They’ve been the cause of devastating fires that have cost lives and massive property loss. When power system managers can do T&D line surveys faster, decisions on maintenance and repairs also come faster.
Frequent inspections may help head off common problems:
- In fire-prone regions, utilities can frequently check areas where high-voltage equipment is surrounded by dry fuels. Images of vegetation encroachment and foliage clearance can be shared across agencies, helping to prevent potential line damage before it happens.
- Drones with thermal imaging sensors can collect data the human eye can’t see. Analysts can examine the temperature differences on equipment to help identify electrical or mechanical malfunctions before they spark fires.
- Managers can keep frequent tabs on encroaching foliage without needing to set foot into difficult terrain or ecologically sensitive areas like wetlands.
Great River Energy, a not-for-profit wholesale electric power cooperative serving 700,000 families, farms, and businesses in Minnesota, uses drones for transmission line inspections. By putting a drone in the air, they can check for pole top rot, inspect insulators, and conduct thermal inspections of splices. And Great River Energy is a Skyward customer, so they manage and oversee their drone operations in Skyward’s Aviation Management Platform.
Rich data collection and analysis by drone
Drones can collect imagery at all angles of a structure, from foundation to top. Easily seeing equipment from above, below, and at level gives managers better data on the condition of all elements in the system, including hard-to-access areas. Plus, some power line abnormalities — like unusual hotspots — may not be caught by a ground inspection crew but can be detected by drone-mounted sensors.
Drones can collect remarkably rich data. When an anomaly is detected, photographs or video from multiple angles can allow field teams to plan with precision. They can pinpoint exactly where to go and what equipment needs fixing, and can plan the repairs, tools, and personnel that are most likely needed — an efficiency improvement.
Drone data can also be processed into 3D models of towers and everything between them: load-carrying cables, wires, insulators, jumpers, and more. These so-called “digital twins,” created using photogrammetry or LiDAR, can be used to map entire power line corridors and their terrain. 3D modeling with drones can be a cost-effective way to visualize projects. And using a tool like PIX4Dinspect, models can be used alongside granular drone data to identify and analyze potential issues.
Line pulling: Using drones to restore power
The use cases above all involve the drone collecting data, but drones can sometimes be used to perform physical work, too. One of the most exciting examples is using drones to pull rope or cable socks that can be used to string power lines between poles or towers. This is especially helpful following disasters such as hurricanes, or in rugged areas.
Southern Company, one of the largest producers of electricity in the U.S. and a Skyward customer, has been using drones to pull electrical lines for years. Harry Nutall, Southern Company’s System Air Director, described the work this way: “Line pulling is one of those aspects that we’ve really had success with. We’re taking cables that we need to stretch across usually very rugged terrain and doing it without involving a truck, somebody hacking through the woods, or a helicopter. We can do it with a drone now and really enhance safety in a big way.”
(You can see footage of line pulling and hear more about Southern Company’s drone operations in this video.)
Future potential of drones for energy & utilities
Keeping an aging electrical grid reliable demands new, innovative solutions. Existing and emerging drone technology will continue to play a big role in helping keep the lights on.
Interested in starting a drone program at your company? Check out Skyward’s Program Start Package.