The Cost of Outages. How Much Damage Can an Animal Cause?


Animal-caused electric outages, like all other outages, can cause direct and consequential damage (such as business interruption) to electric utility facilities, C&I customers, residential utility customers and critical public facilities.

Impact on Electric Utilities and Commercial and Industrial Companies That Own Substations

Electric utilities face a wide range of potential impacts from animal-caused contact outages with a number of variables driving the severity of the outage event from X to Y (see Table 1). These variables range from location, animal type, load type, time of day, weather conditions, equipment design and protection schemes. A minor or low-impact event typically is of a very short duration, perhaps caused by an operating recloser or a blown sectionalizing fuse, affecting a limited number of residential customers or limited commercial and/or industrial area.

Animal-Caused Outage Impact (Utility View of Costs) - Table 1

Major or high-impact outages have further-reaching impacts affecting multiple stakeholders and can pose significant financial costs to both utility and C&I companies. Consider the damage to substation equipment, utility worker overtime hours to diagnose and repair, and possible fines and lawsuits. These outages can result in major equipment failure — such as reclosers, substation transformers, circuit breakers or powerline equipment, or any combination of electrical equipment. C&I companies may face double the risk because they not only experience a loss in productivity and revenues but also may suffer the same potential equipment damage to their own substation or powerline equipment.

Impact to Customers

Outage impacts extend beyond the utility companies. To demonstrate just how damaging outages can be, four outage scenarios, presented in Table 2, provide a range of possibilities to provide context to the outage impact and the span and spectrum of outage types, location and impacted customer numbers. These scenarios demonstrate the variability of an outage event; however, each event presents its unique and lasting impact on the customer, further reflecting the importance of developing a wildlife mitigation plan.

Outage Scenarios for Animal-Caused Contact Outages - Table 2

Impacts Beyond the Typical Customer

Electric outages are particularly troublesome to public service facilities since police and fire departments have to provide assistance to manage areas without power. Police must respond to an increased number of “no power” burglar alarm calls, traffic light outages, calls from members of the public reporting outages and increased instances of crime.9 Fire departments must monitor critical buildings, respond to false alarms and may be required to support certain facilities that have fire pumps requiring electricity. Water and sewer departments face similar challenges with pumps that experience shutdowns or limited functionality due to reduced power supply from backup power generators.

Critical services, including hospitals, airports and railroads, also experience great risk when the lights go out. While these facilities often have backup power generation, it only supplies a limited number of essential systems for a given period of time. Considering the life-critical services these facilities provide, an electric outage is not just an inconvenience but may become a human-life safety issue. Examples include an outage at a Veterans Affairs Medical Center in Tennessee caused by an animal; squirrels that cut power to a regional airport in Virginia; three outages at the Los Angeles airport; and two outages at NASDAQ’s facility where trading was affected, causing certain economic harm.10,11 Had loss of human life occurred due to any of these preventable outages, litigation risk would have very likely increased dramatically, further reflecting the need to act swiftly to reduce this outage cause.



[1] Mooallem, J. (2014) “Squirrel Power!” Available at: (Accessed: 20 July 2016).

[2] Economic Benefits Of Increasing Electric Grid Resilience to Weather Outages. Available at: (Accessed: 2 May 2016).

[3] “U.S. power grid could be knocked out by a handful of substation attacks.” TV-NovostiAutonomousNonprofitOrganization (2016). Available at: (Accessed: 12 August 2016).

[4]  2 Paragraphs (2016) Squirrels – #1 threat to US electrical grid. Available at: (Accessed: 11 July 2016).

[5]  International Energy Agency (2009). Energy Policies of IEA Countries - Canada 2009 Review. Paris: OECD/IEA. ISBN 978-92-64-06043-2.

[6]  Transmission. Available at: (Accessed: 1 August 2016).

[7]  Kemper, C. (2016) “Animal Behavior and Protection at Electric Substations.” Interview with Colin Hassett on 10 March 2016.

[8]  CyberSquirrel1 (2015) CyberSquirel1.Com. Available at: (Accessed: 1 August 2016).

[9]  University of Lincoln, “New research warns world to prepare for power outages.” ScienceDaily,

[10]      Energy and Environmental Economics, Inc. (2005). The Cost of Wildlife-Caused Power Outages to California’s Economy. California Energy Commission, PIER Energy-Related Environmental Research. CEC-500-2005-030.

[11]      Mooallem, J. (2014) Squirrel power! Available at: (Accessed: 13 July 2016).

This post is the third in a series of seven excerpts from an electric utility industry white paper prepared by FTI Consulting, entitled, THE CASE FOR ELIMINATING ANIMAL-CAUSED OUTAGES IN ELECTRIC SUBSTATIONS AND ON POWERLINES. The full white paper may be downloaded by clicking here.

Darren Barnett

Darren Barnett, VP MEPP (Manufacturer’s Equipment Protection Program) / Technical Services, holds a degree in Electrical Engineering Technology from Louisiana Tech University and has over 28 years of experience in the electric power distribution industry. Darren’s career started as a design engineer for a major transformer and components manufacturer. From there he advanced to positions of increasing responsibility, including Quality Assurance Manager, Engineering Manager and Vice President of Components Operations. Darren is an active member of IEEE and was on the committee that developed the 1656 -2010 testing guide for wildlife mitigation products.

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