Every year, climbing animals that find their way into US substations cause power outages that affect hundreds of thousands of customers and cost millions in repairs, man-hours, and lost business.

The TransGard team, which has installed its patented animal-prevention fencing at more than 2,000 substations, selected this year’s list from among hundreds of outages.

Squirrels were still top of the list, but snakes, raccoons, domesticated cats and rats were responsible for some of the worst outages of 2013, causing significant equipment damage and leaving thousands of customers without power. The list, in date order, includes:

  • Raccoon: in March, a raccoon that crawled into a substation and damaged equipment was to blame for a power failure that knocked out electricity to 9,500 homes and businesses in San Benito, Texas
  • Snake: when a snake interfered with a substation in Marshall County, Kentucky in May, approximately 7,153 residents and businesses lost power. West Kentucky Rural Electric Cooperative has installed two TransGard systems to avoid this type of incident in the future
  • Squirrel: in July, a squirrel knocked out power for nearly 10,000 people in Multnomah County, Oregon, where just days before a squirrel incident caused 5,000 customers to lose power in neighbouring Gladstone
  • Cat: approximately 8,400 customers in the Museum District in Houston lost power in November when a cat managed to get inside a substation and blow a breaker
  • Rat: In December, around 1,400 residents in Chehalis, Washington, lost power when a rat crawled into power equipment, resulting in a shortage that burned out a breaker and caused the power transformer fuses to burn out