Since the Northeast Blackout of 2003, the federal government has focused on tree-to-power-line contact as a major grid reliability concern. And Public Utility Commissions  are increasingly likely to tie electric utility profits to system reliability performance.

Though electric utilities hire crews to patrol distribution lines, and trim trees every three years or so, the effects that wind, snow and ice will have can only be estimated by such patrols. Even if an area has just been patrolled, these factors can eliminate clearances in minutes. Off-ROW trees falling into distribution lines are the most common cause of power outages. But tree-to-line contact inevitably produces detectable power line arcing.

A network of solar-powered Fire Scout X3s along distribution lines can continuously watch for arcing, and report the grid coordinates where arcing is detected in real time. X3 arc detections can be relayed back to a central office for computer display on a map via mesh radio networks, satellite uplinks, power line carrier or leased lines.  

When winds, snow or ice drive a tree into contact with power lines, the X3 arcing report alerts the utility to the need for better clearances. By sending crews out to investigate, subsequent power outages can be prevented.

When a “hazard tree” falls into power lines in wet weather, downed lines and even unforeseen outages can result. The X3 report can pinpoint where the problem is, enabling repair crews to be dispatched. 

In times of high fire danger, any arcing report takes on increased urgency, and can be used to alert firefighters and then shut down power for their protection if necessary.

X3s do not need a direct line of sight to the arcing because they are non-imaging.

By spatially integrating reflected arc signals over their hemispherical field of view, they can see arcing that humans can’t – typically a half mile away. With direct line of sight, the X3 can see arcing up to a mile away.

The X3’s signal processing can distinguish an arc welder from an arcing power line, so avoids false alarms associated with arc welders.