Journal of Critical Infrastructure Policy Volume 1, Number 2, Fall/Winter 2020 | Page 44

Journal of Critical Infrastructure Policy
rural electric cooperatives , 168 investor-owned utilities ( that serve slightly over 70 % of all U . S . electricity customers ), public utilities , regional transmission organizations ( RTOs ), independent system operators ( ISOs ), and power generation companies . A 2017 study estimated the U . S . electric power enterprise workforce had about 2.7 million direct workers who maintain , install , and operate the Grid ( BMJ 2017 ). The study estimated that the electric power industry contributed $ 880 Billion to the nation ’ s Gross Domestic Product .
Grid Vulnerabilities
The Grid is susceptible to natural hazards and malevolent human threats that can trigger wide-spread , long-term disruptions . Cascading CI and SASC failures are difficult to bound ( NIAC 2018 ). Superstorms and hurricanes , extreme seismic events , and naturally-occurring geomagnetic disturbances ( GMDs ) triggered by solar storms are natural hazards that can and have assaulted the Grid . The earth is overdue for a major geomagnetic disturbance of the magnitude of the Carrington Event , which set telegraph poles and offices across North American and Northern Europe ablaze in 1859 ( Riley 2016 ). There has been a marked increase in the frequency , complexity , and sophistication of cyberattacks and other malevolent human Grid intrusions ( INL 2016 , NAS 2017 ). Coordinated cyber and physical attacks have the potential to challenge the Grid in ways that cannot be fully simulated or addressed in advance . In addition , a long-term , large geographic scope outage could be produced by an electromagnetic pulse ( EMP ) caused by a high-altitude nuclear detonation ( HEMP ), lower altitude detonation ( SREMP ), or through an intentional electromagnetic interference ( IEMI ) event ( NCC 2019 ). The cascading effects of a Grid blackout of more than several months in any nation would put the lives of its entire population at risk .
The Grid ’ s behavior during normal circumstances is a carefully choreographed balance between spatially dependent , continuously changing , electric load and electricity generation . Yet the system ’ s overall behavior is difficult to simulate at the desired level of granularity because it embodies so many distinct and competing physical phenomena , geospatial and electrical relationships , network scales , interdependencies , and failure modes .
Most disruptions of electric service in the U . S . occur at the local distribution level . Damage to distribution system power lines and transformers caused by animals is a leading cause of these more frequent localized power outages ( APPA 2019 ). More serious problems arise when these anomalies flow upstream into the remainder of a local distribution company ’ s service territory or into the bulk power energy system ( BES ) and bulk power system ( BPS ) to impact much larger regions and human populations .
The highly discussed cascading 2003 Northeast Blackout that interrupted electric service for two days to about 50 million customers , illustrates the rapid
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