Squirrels are often viewed as the most likely suspect of an animal-caused outage. But in Texas, the problem often doesn’t scamper in — it slithers.
CoServ Electric, which operates 29 substations across North Texas, experienced multiple outages in 2019 from bull, corn, and rat snakes crawling into substations. Each outage cost thousands of dollars in repairs and man-hours, and it tested the patience of customers accustomed to receiving reliable power.
“Snakes will enter a substation for food, warmth, even for the machinery vibration,” says Perry Ancell, CoServ’s Systems Operations Superintendent. “If a snake interferes with bushings or other components, it can cause a service outage for thousands of customers.”
CoServ had developed its own snake deterrent consisting of electrified wire on PVC pipe and grounded chicken wire that surrounded the substation. But it turned out to be ineffective: Animals would come in contact with the fence and short it out, leaving the fence inactive and the substation unprotected.
When CoServ experienced five large substation outages in the spring of 2019 — two of them at the same substation about a week apart — Ancell realized that CoServ needed a new approach. He reached out to TransGard.
CoServ, along with its transmission and generation partner Brazos Electric, has installed TransGard fences with snake panels at five substations and is considering installing them at all of its substations over the next several years. The snake panels are part of a fence system that surrounds the substation, and they deliver an electric shock that discourages animals — including snakes as small as a quarter-inch in diameter — from climbing over or through it. The modular fence includes a gate that allows workers to access the substation, and it can also be easily reconfigured to allow access for a truck, crane, or other maintenance equipment.
The investment is well worth it, according to Greg Ward, CoServ’s Senior Vice President of Field Operations.
“Relative to the amount of money that we spend on a substation, snake deterrent fencing is a small investment,” Ward says. “It’s pennies on the dollar for what we might have to spend on repairing equipment after an outage.”