Dominion Energy has expanded its use of drones to enhance the inspection and maintenance of its solar farms, power lines, and other critical infrastructure. The company’s Unmanned Systems Group, consisting of 10 Federal Aviation Administration-certified pilots, operates a fleet of 50 specialized drones designed to perform a range of tasks, from aerial inspections to underwater assessments.
In a recent deployment at the Colonial Trail West solar farm in Surry County, Virginia, a drone pilot identified overheating solar panels linked to a sudden drop in power output. The 142-megawatt solar farm, consisting of 130 lines of solar panels each extending between 300 and 500 feet, had one of its 23 “drones in the box” stationed nearby at the Spring Grove substation. Pilot Aaron Colgrove remotely guided the drone to conduct a thermal imaging sweep, detecting a cluster of overheated panels that were underperforming. The use of thermal sensors allowed the team to quickly diagnose the issue without requiring on-site personnel to physically inspect the area.
Dominion’s drone program supports a variety of operations difficult or hazardous to perform manually. Besides solar farm monitoring, the drones survey power lines, substations, and inaccessible areas of power plants. They also conduct security checks, environmental surveys, and detailed mapping. Some drones operate from secured cabinets, charging autonomously and equipped with cellular connectivity that enables flights beyond the pilot’s direct line of sight, in compliance with FAA regulations.
Among the fleet is a vertical take-off-and-landing (VTOL) drone capable of flying at speeds of up to 45 miles per hour over extensive stretches of high-voltage lines. This VTOL is equipped with lidar sensors that generate precise three-dimensional point clouds, helping pilots maintain safe distances from power lines while detecting conditions such as vegetation encroachment or ground erosion supporting utility poles. This technology allows inspections to be conducted more efficiently and thoroughly than traditional ground-based methods.
The Unmanned Systems Group also operates submersible drones to inspect underwater structures like tower foundations and submarine cables, including those related to Dominion’s offshore wind farm development 25 miles off Virginia Beach. Additionally, the program employs walking drones, such as one nicknamed Odie, which navigate hazardous terrain to assess storm damage without exposing linemen to risks from downed power lines or unstable debris.
Safety remains a primary focus for the operation. Managers emphasize that selecting the appropriate drone for each job depends on factors including battery life, payload capacity, speed, and the ability to avoid obstacles autonomously. For close-up inspections, smaller drones can approach poles and other infrastructure to provide detailed imagery, enabling technicians to identify issues such as loose bolts or damaged components with greater precision than ground inspections allow.
By integrating advanced drone technology, Dominion Energy aims to improve the reliability and safety of its electric grid while reducing the time and hazards associated with traditional inspection methods.