Risk and Asset Management Strategies

Good data provides the ability to make appropriate decisions regarding an animal-caused outage problem. Specific animal-caused outage metrics need to be identified and tracked during monthly asset management meetings similar to other operational reliability measures, such as System Average Interruption Duration Index (“SAIDI”), System Average Interruption Frequency Index (“SAIFI”) and Customer Average Interruption Duration Index (“CAIDI”). A more complete review of operational challenges can be performed, and the appropriate actions may be prioritized and acted upon. Suggested measures include:

  • Count of animal-caused outages (segmented by voltage):
    • System-wide
    • By planning area or region
  • Percentage of animal-caused outages compared with total outage numbers:
    • System-wide
    • By planning area or region
  • Number of substations with an Animal Protection Plan (deployment measure):
    • Planned vs. actual by voltage level
  • Number of substations inspected for animal-intrusion risk (i.e., damaged fences and damage mitigation equipment):
    • Planned vs. actual
    • Whether outage mitigation is complete or comprehensive
  • Number of lines/circuits inspected for animal-intrusion risk:
    • Planned vs. actual
  • Work plan completion for animal-caused outage mitigation equipment installations:
    • Planned vs. actual
  • Outage root-cause analysis completion rate (percentage)
  • Top 10 list of substations with highest animal-caused outages for the fiscal year (i.e., poor performer)

However, before acting on the results of the data, utilities must develop an asset management strategy that acknowledges the problem and their response to it. While animal-contact outage goals currently are not mandated by regulatory bodies, utilities should set aggressive goals at the asset class level to assist with the identification of the riskiest assets. Table 3 recommends the risk categorization that should be used to help identify and then target the riskiest assets so the prioritization for animal-contact mitigation can be included in the annual planning process. Once these assets are placed on the work plan for the appropriate fiscal year, tracking progress against the plan should be included in the regular monthly review period.

Table 3 – Recommended Animal-Contact Risk Characterization by Asset Type

Additionally, the dynamic nature of animal movement and migration, along with ever-changing environmental factors (e.g., urban expansion, industrial buildup, oil or shale exploration) requires a periodic (at least annual) review of substation assets that already have animal-contact mitigation equipment installed (see Figure 5). The results of this assessment should lead to root-cause analysis and then a plan for further mitigation — be it replacing the damaged animal-protection equipment or completely redesigning a mitigation plan. These considerations for existing assets may then be included in the risk scoring of the greater asset portfolio.

Cost Recovery Strategies

Since the installation of substation animal protection products is in the public’s interest, it is important for utilities to install the most appropriate solution that will correct the situation. While the cost and the sheer number of substations make the cost to implement a complete solution seemingly difficult to implement in a cost-constrained environment, utilities should capitalize the cost of these installations so they are included in the rate recovery process.

The capitalization of construction costs for a new substation installation can likely occur if the animal protection method is included early in the project initiation process. There is an additional benefit to installing the right protection at a new substation during the construction phase because the downtime that would otherwise be necessary to retroactively install animal guards, for example, is eliminated. Existing substations also can benefit from the capitalization of the installation if the costs are structured properly. Further, proactively installing animal protection yields additional cost benefits in the form of avoided costs that would otherwise be realized by outages.

Typically, retroactive installations would be a non-recoverable O&M expense; however, a capitalized cost case could be justified by meeting certain conditions. Specifically, if an animal protection device is categorized as a “betterment”, where it adds to the productive capacity or improves the efficiency of an existing facility, it could be capitalized.13

REFERENCES

[1] Mooallem, J. (2014) “Squirrel Power!” Available at: http://www.nytimes.com/2013/09/01/opinion/sunday/squirrel-power.html (Accessed: 20 July 2016).

[2] Economic Benefits Of Increasing Electric Grid Resilience to Weather Outages. Available at: http://energy.gov/sites/prod/files/2013/08/f2/Grid%20Resiliency%20Report_FINAL.pdf (Accessed: 2 May 2016).

[3] “U.S. power grid could be knocked out by a handful of substation attacks.” TV-NovostiAutonomousNonprofitOrganization (2016). Available at: https://www.rt.com/usa/power-grid-knocked-out-substations-706/ (Accessed: 12 August 2016).

[4]  2 Paragraphs (2016) Squirrels – #1 threat to US electrical grid. Available at: http://2paragraphs.com/2016/01/squirrels-1-threat-to-us-electrical-grid/ (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: http://www.eei.org/issuesandpolicy/transmission/Pages/default.aspx (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: http://www.cybersquirrel1.com (Accessed: 1 August 2016).

[9]  University of Lincoln, “New research warns world to prepare for power outages.” ScienceDaily, https://www.sciencedaily.com/releases/2014/01/140127093033.htm.

[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: http://www.nytimes.com/2013/09/01/opinion/sunday/squirrel-power.html?_r=0 (Accessed: 13 July 2016).

[12]      Mitigation of Animal-Caused Outages for Distribution Lines and Substations, (1999) EPRI, Palo Alto, Calif. 1999. Report TE-114915.

[13]      DeMontigny, M., & Horn, H. (2012). Guide to Accounting for Utilities and Power Companies. Retrieved September 19, 2016, from https://www.pwc.com/us/en/cfodirect/assets/pdf/accounting-guides/pwc_utilities_power_2013.pdf

[14]      Heck, N. and Sutherland, T. (2016) Electric Energy Online. Available at: http://www.electricenergyonline.com/show_article.php?mag=92&article=742 (Accessed: 6 April 2016).

[15]      Heck, N. and Sutherland, T. (2016) Electric Energy Online. Available at: http://www.electricenergyonline.com/show_article.php?mag=92&article=742 (Accessed: 6 April 2016).

[16]      Heck, N. and Sutherland, T. (2016) Electric Energy Online. Available at: http://www.electricenergyonline.com/show_article.php?mag=92&article=742 (Accessed: 6 April 2016).

[17]      Heck, N. and Sutherland, T. (2016) Electric Energy Online. Available at: http://www.electricenergyonline.com/show_article.php?mag=92&article=742 (Accessed: 6 April 2016).

Asset Management Planning for Wildlife Outage Mitigation Planning

So, what should utilities do in a situation where they are having an animal-caused outage issue and do not know where to start when they are planning to install a new substation?

An animal-caused outage mitigation mindset must exist within all levels of a utility’s asset management process in order to completely manage the issue (see Figure 5). Utilities need to look internally to all of their processes to understand where there are examples of practices that work well and should be reinforced and also recognize areas of opportunity. Detailed in this section is a high-level review of the areas that should be reviewed, analyzed, understood, improved upon or implemented, when necessary, to support the drive toward zero animal-caused outages.

Asset Management Process with the Animal Protection Component Included Figure 5

You Get What You Measure: The Industry View

In order to understand the animal-intrusion issue, including the cause of the issue, utilities need to measure, establish targeted goals and then make informed decisions to meet or exceed those goals.

Utilities must begin by reviewing their management processes for collecting data relating to animal-intrusion caused outages and equipment damage. Utilities need to be more rigorous when it comes to collecting outage data. A lack of data or even inaccurate data can lead to inaction or inappropriate action being applied to a problem. There are a number of reasons why utilities may have difficulty obtaining data; however, performing a review of the data collection methods and driving improvements to the areas of weakness will address this threshold issue. Listed below are some of the top reasons why data has been incomplete or inaccurate and should be used to eliminate reasons why poor data collection processes exist:

  • A low-risk outage (momentary outage, limited customers affected, occurrence at night, etc.)
  • Data collection did not occur (operator/field personnel were busy, etc.)
  • Inconsistent or nonexistent reporting standards (operational drift)

Root-cause analysis, a necessary next step

While time consuming, performing root-cause analysis on a regular basis promotes the discipline necessary to completely understand the cause of any animal-contact issue. The analysis also will rapidly expose common themes, allowing for an informed decision on next steps and an optimized investment in equipment protection. Applying the same practices utilities commonly use for their existing safety-based root-cause analysis is an excellent start to ensuring that this methodology is applied correctly and swiftly.

 

REFERENCES

[1] Mooallem, J. (2014) “Squirrel Power!” Available at: http://www.nytimes.com/2013/09/01/opinion/sunday/squirrel-power.html (Accessed: 20 July 2016).

[2] Economic Benefits Of Increasing Electric Grid Resilience to Weather Outages. Available at: http://energy.gov/sites/prod/files/2013/08/f2/Grid%20Resiliency%20Report_FINAL.pdf (Accessed: 2 May 2016).

[3] “U.S. power grid could be knocked out by a handful of substation attacks.” TV-NovostiAutonomousNonprofitOrganization (2016). Available at: https://www.rt.com/usa/power-grid-knocked-out-substations-706/ (Accessed: 12 August 2016).

[4]  2 Paragraphs (2016) Squirrels – #1 threat to US electrical grid. Available at: http://2paragraphs.com/2016/01/squirrels-1-threat-to-us-electrical-grid/ (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: http://www.eei.org/issuesandpolicy/transmission/Pages/default.aspx (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: http://www.cybersquirrel1.com (Accessed: 1 August 2016).

[9]  University of Lincoln, “New research warns world to prepare for power outages.” ScienceDaily, https://www.sciencedaily.com/releases/2014/01/140127093033.htm.

[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: http://www.nytimes.com/2013/09/01/opinion/sunday/squirrel-power.html?_r=0 (Accessed: 13 July 2016).

[12]      Mitigation of Animal-Caused Outages for Distribution Lines and Substations, (1999) EPRI, Palo Alto, Calif. 1999. Report TE-114915.

[13]      DeMontigny, M., & Horn, H. (2012). Guide to Accounting for Utilities and Power Companies. Retrieved September 19, 2016, from https://www.pwc.com/us/en/cfodirect/assets/pdf/accounting-guides/pwc_utilities_power_2013.pdf

[14]      Heck, N. and Sutherland, T. (2016) Electric Energy Online. Available at: http://www.electricenergyonline.com/show_article.php?mag=92&article=742 (Accessed: 6 April 2016).

[15]      Heck, N. and Sutherland, T. (2016) Electric Energy Online. Available at: http://www.electricenergyonline.com/show_article.php?mag=92&article=742 (Accessed: 6 April 2016).

[16]      Heck, N. and Sutherland, T. (2016) Electric Energy Online. Available at: http://www.electricenergyonline.com/show_article.php?mag=92&article=742 (Accessed: 6 April 2016).

[17]      Heck, N. and Sutherland, T. (2016) Electric Energy Online. Available at: http://www.electricenergyonline.com/show_article.php?mag=92&article=742 (Accessed: 6 April 2016).

The Evolution and Application of Outage Mitigation Methods

So how do you best protect against animal-based threats, and is it even possible to achieve zero animal-caused outages once applied?

IEEE-1264TM, “IEEE Guide for Animal Deterrents for Electric Power Supply Substations,” discusses many strategies to combat the issue, and this standard examines various strategies deployed, including simulated natural predators, noisemakers, cover-up materials, animal fences and barriers, nest relocation, increased insulator size and spacing, and construction of indoor substations, to name a few. Largely, 10-20 years ago, these methods were experimental in nature when introduced; yet time and experience have exposed both successful and unsuccessful methods.

Data and experience have suggested that the least effective methods include deterrents (see Figure 4) such as simulated predators, noisemakers and smells, as they have shown to exhibit a limited life span before animal adaptation.12 Animal behavior experts explain that this is primarily because animal instinctual behavior leads animals to initially be frightened by these devices, while increased exposure allows them to test and naturally realize that these harmless devices will not hurt them. Scents of predators have been used to simulate a similar threat, which also worked initially, only to have the scent wear off or wash away or the animals became used to the smell and, consequently, aware of the lack of threat.

Various Types of Animal Protection and Their Best Applications – Figure 4

 

Animal Fences

Some other outage mitigation solutions include limiting animals’ ability to gain access to equipment beyond the protection afforded by standard fencing. One example is the installation of electrified fencing surrounding equipment that is more prone to land-based animal intrusion. When applied to areas that tend to be more problematic, the fence can be more or less expansive as needed. A limitation associated with these systems is that while they are effective for ground-based animals, they do not keep avian animals out of the area (with open sky access). Burrowing animals still could intrude; however, this risk is limited because the animals do feel the electric field created by the fence and tend to avoid the area.

 

Animal Guards
Installing animal guards is another approach. Animal guards are mounted on equipment to block animals from getting into electrified conductors and can provide protection from a limited type of animal contact, but certain animals that are more resourceful (e.g., squirrels) have shown their ability to bypass these animal guard protections. These are considered somewhat effective, low-cost solutions for protection of distribution transformers or any other lower cost, short-lead-time equipment. In fact, most utilities report that they proactively install this type of equipment on a transformer when a new installation or replacement is commissioned.

 

Animal Cover-up
The most complete and proven method involves the cover-up design approach, where insulation covers are added to electrified equipment and/or grounded structures in the vicinity of energized risk points, thus providing improved insulation and protection in a specific and targeted way. This method dramatically increases the span that’s necessary for an animal to bridge the contact points and minimizes risks relating to gaps being accessible to crawling animals or inquisitive birds. Cover-up typically is applied to equipment in an area that needs additional span distances, including transformer bushings, circuit breaker bushings and others that are most vulnerable to animal contact.

This design eliminates high-risk bridging and does not allow animals to bypass the protection by climbing around or finding another access point for intrusion, which can be a limitation of other protection methods. Additionally, the risk of bird intrusion is eliminated since the cover-up guard protects the equipment in all directions, not just for land-based intrusion. In practice, cover-up protection eliminates the root cause of animal intrusion by increasing the span distance rather than managing the symptom of animal contact.

Two main types of cover-up solutions are available, including a one-size-fits-all or a customized cover-up design, which is built to precisely fit specific equipment types. For a cover-up to work most effectively, it should completely cover the equipment it surrounds because ill-fitting covers can be bypassed by animals or can leave gaps and spaces where a contact or nesting can be made. While the best covers will maintain a tight fit to preclude intrusion, it also is critical that they are durable. IEEE-1656TM is an engineering specification that establishes guidelines for animal protection products, such as ultraviolet exposure protection, impact resistance, salt exposure and flame resistance, ensuring that maintenance is virtually nonexistent. This is important not only because it ensures that a long-lasting solution is deployed, but it also has cost recovery implications.

 

Protection Selection Considerations
When selecting cover-up protection, it is essential to consider long-term concerns that will allow for the cost-effective operation and inspection of the equipment the cover-up protects. Should the equipment require access in a way that necessitates the cover-up’s frequent removal, ease of doing so is a key factor. An additional consideration should include the ability to perform infrared inspections with minimal or no extra work required. Any additional work that is required to remove and then reapply a cover-up during maintenance could be considered extra operating Operations and Maintenance (“O&M”) expense, reflecting another cost driver and proving the value of finding the right cover-up product.

 

REFERENCES

[1] Mooallem, J. (2014) “Squirrel Power!” Available at: http://www.nytimes.com/2013/09/01/opinion/sunday/squirrel-power.html (Accessed: 20 July 2016).

[2] Economic Benefits Of Increasing Electric Grid Resilience to Weather Outages. Available at: http://energy.gov/sites/prod/files/2013/08/f2/Grid%20Resiliency%20Report_FINAL.pdf (Accessed: 2 May 2016).

[3] “U.S. power grid could be knocked out by a handful of substation attacks.” TV-NovostiAutonomousNonprofitOrganization (2016). Available at: https://www.rt.com/usa/power-grid-knocked-out-substations-706/ (Accessed: 12 August 2016).

[4]  2 Paragraphs (2016) Squirrels – #1 threat to US electrical grid. Available at: http://2paragraphs.com/2016/01/squirrels-1-threat-to-us-electrical-grid/ (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: http://www.eei.org/issuesandpolicy/transmission/Pages/default.aspx (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: http://www.cybersquirrel1.com (Accessed: 1 August 2016).

[9]  University of Lincoln, “New research warns world to prepare for power outages.” ScienceDaily, https://www.sciencedaily.com/releases/2014/01/140127093033.htm.

[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: http://www.nytimes.com/2013/09/01/opinion/sunday/squirrel-power.html?_r=0 (Accessed: 13 July 2016).

[12]      Mitigation of Animal-Caused Outages for Distribution Lines and Substations, (1999) EPRI, Palo Alto, Calif. 1999. Report TE-114915.

[13]      DeMontigny, M., & Horn, H. (2012). Guide to Accounting for Utilities and Power Companies. Retrieved September 19, 2016, from https://www.pwc.com/us/en/cfodirect/assets/pdf/accounting-guides/pwc_utilities_power_2013.pdf

[14]      Heck, N. and Sutherland, T. (2016) Electric Energy Online. Available at: http://www.electricenergyonline.com/show_article.php?mag=92&article=742 (Accessed: 6 April 2016).

[15]      Heck, N. and Sutherland, T. (2016) Electric Energy Online. Available at: http://www.electricenergyonline.com/show_article.php?mag=92&article=742 (Accessed: 6 April 2016).

[16]      Heck, N. and Sutherland, T. (2016) Electric Energy Online. Available at: http://www.electricenergyonline.com/show_article.php?mag=92&article=742 (Accessed: 6 April 2016).

[17]      Heck, N. and Sutherland, T. (2016) Electric Energy Online. Available at: http://www.electricenergyonline.com/show_article.php?mag=92&article=742 (Accessed: 6 April 2016).

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.

 

REFERENCES

[1] Mooallem, J. (2014) “Squirrel Power!” Available at: http://www.nytimes.com/2013/09/01/opinion/sunday/squirrel-power.html (Accessed: 20 July 2016).

[2] Economic Benefits Of Increasing Electric Grid Resilience to Weather Outages. Available at: http://energy.gov/sites/prod/files/2013/08/f2/Grid%20Resiliency%20Report_FINAL.pdf (Accessed: 2 May 2016).

[3] “U.S. power grid could be knocked out by a handful of substation attacks.” TV-NovostiAutonomousNonprofitOrganization (2016). Available at: https://www.rt.com/usa/power-grid-knocked-out-substations-706/ (Accessed: 12 August 2016).

[4]  2 Paragraphs (2016) Squirrels – #1 threat to US electrical grid. Available at: http://2paragraphs.com/2016/01/squirrels-1-threat-to-us-electrical-grid/ (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: http://www.eei.org/issuesandpolicy/transmission/Pages/default.aspx (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: http://www.cybersquirrel1.com (Accessed: 1 August 2016).

[9]  University of Lincoln, “New research warns world to prepare for power outages.” ScienceDaily, https://www.sciencedaily.com/releases/2014/01/140127093033.htm.

[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: http://www.nytimes.com/2013/09/01/opinion/sunday/squirrel-power.html?_r=0 (Accessed: 13 July 2016).

How Do Animal-Caused Outages Occur?

Why do animals pose a threat in the first place? Why would they even be attracted to energized electrical equipment in substations that have fences and complicated climbing structures?

Animals seek out substations for the promise of food, shelter, warmth, perching and even general curiosity. In fact, these drivers are why animals in open field locations seek out electrical substations and powerline structures in areas they otherwise would avoid. An animal can bridge, or connect, an energized source to a contact point with a different voltage potential, causing a fault (see Figure 3). Substations are ripe for electrical bridging opportunities due to the many exposed electrical contact points. Additionally, substations built in open areas that don’t have many trees or other nesting or roosting opportunities can attract birds to nest or roost given the lack of other suitable locations to do so.7

Transmission Substation Voltage Level (Bulk Electric System) Contact Risk

The animal-contact risk does vary by the voltage class of equipment and the transmission voltage level. The high-voltage electric system, usually 69kV to 750kV+, benefits from increased insulator spacing that limits outage exposure from ground-based animals such as squirrels. The transmission system, however, does experience higher outage risk from birds with significant wing span lengths that include osprey, among others. Transmission systems also can experience outages due to streamers from bird droppings while in flight since higher voltages can track over larger air-gap distances than lower voltages.

Subtransmission Substation Voltage Level Contact Risk

Subtransmission voltage, typically 34.5kV to 69kV, presents a unique challenge because the wide voltage range yields equipment spacing similar to both transmission and distribution. The higher end of the voltage range benefits from increased insulator spacing similar to high voltage transmission but also has the same risks of bird contact. The lower end of the voltage range experiences similar outage risks as the distribution level, including increased contact due to ground-based animals, such as squirrels and raccoons.

Distribution Substation Voltage Level Contact Risk

The distribution voltage range, typically 2.4kV to 35kV, has the closest electrical equipment spacing of all the voltage classes. This close spacing results in a risk to a wide range of land- and air-based animal types that are large enough to bridge the electrical shorting distance, including squirrels, raccoons, snakes, birds of various sizes and many others. Further, the data presented in Figure 3 indicates squirrels, by far, are the biggest offenders to animal-caused outages, and, thus, mitigation efforts with respect to squirrels should be a major focus area for utilities.

Spacing of Insulators Indicating Shorting Distance, Listing a Sample of Animals That Commonly Bridge the Shorting Distance (not to scale)
Figure 3

REFERENCES

[1] Mooallem, J. (2014) “Squirrel Power!” Available at: http://www.nytimes.com/2013/09/01/opinion/sunday/squirrel-power.html (Accessed: 20 July 2016).

[2] Economic Benefits Of Increasing Electric Grid Resilience to Weather Outages. Available at: http://energy.gov/sites/prod/files/2013/08/f2/Grid%20Resiliency%20Report_FINAL.pdf (Accessed: 2 May 2016).

[3] “U.S. power grid could be knocked out by a handful of substation attacks.” TV-NovostiAutonomousNonprofitOrganization (2016). Available at: https://www.rt.com/usa/power-grid-knocked-out-substations-706/ (Accessed: 12 August 2016).

[4]  2 Paragraphs (2016) Squirrels – #1 threat to US electrical grid. Available at: http://2paragraphs.com/2016/01/squirrels-1-threat-to-us-electrical-grid/ (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: http://www.eei.org/issuesandpolicy/transmission/Pages/default.aspx (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: http://www.cybersquirrel1.com (Accessed: 1 August 2016).

[9]  University of Lincoln, “New research warns world to prepare for power outages.” ScienceDaily, https://www.sciencedaily.com/releases/2014/01/140127093033.htm.

[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: http://www.nytimes.com/2013/09/01/opinion/sunday/squirrel-power.html?_r=0 (Accessed: 13 July 2016).

The Impact of Animal-Caused Outages

The growing reliance on energy and the implications of its interruption in residential homes, commercial and industrial (“C&I”) facilities, and government agencies places an increasing burden on utilities to provide a more reliable power supply than ever experienced in the history of the electric system (see Figure 1).

Impact on Utilities and Their Customers

Figure 1

Impact of Animal Outages

Despite this increasing and strategically important mandate, animal intrusion into utility and industrial substations causes a significant number of outages that are highly preventable. In fact, this well-known issue represents up to 20 percent of all power outages, which are preventable if utilities and industrial customers adopt programs to assess intrusion risk, track and investigate occurrences, and implement effective protection measures.1

In order for utilities to prevent these animal-caused outages, utilities need to develop animal intrusion policies and strategies, processes, metrics and investment programs to reduce and eliminate animal-caused outages in substations and on powerlines. Technology exists today that could drive this outage risk toward zero, including the application of protective guards and cover-up solutions. Shielding or isolating contact points that are otherwise accessible to animals virtually eliminates the ability of an animal or bird to bridge energized sources, causing an electrical contact outage.

 

REFERENCES

[1] Mooallem, J. (2014) “Squirrel Power!” Available at: http://www.nytimes.com/2013/09/01/opinion/sunday/squirrel-power.html (Accessed: 20 July 2016).