Date:  Nov. 14, 2012




Electric Power Grid 'Inherently Vulnerable' to Terrorist Attacks;

Report Delayed in Classification Review, Will Be Updated


WASHINGTON — The U.S. electric power delivery system is vulnerable to terrorist attacks that could cause much more damage to the system than natural disasters such as Hurricane Sandy, blacking out large regions of the country for weeks or months and costing many billions of dollars, says a newly released report by the National Research Council. 


According to the report, the security of the U.S. electric power system is in urgent need of attention.  The power grid is inherently vulnerable physically because it is spread across hundreds of miles, and many key facilities are unguarded.  This vulnerability is exacerbated by a reorganizational shift in the mid-1990s, prompted by federal legislation to introduce competition in bulk power across the country, resulting in the transmission network being used in ways for which it was not designed.  As a result, many parts of the bulk high-voltage system are heavily stressed, leaving it especially at risk to multiple failures following an attack.  Important pieces of equipment are decades old and lack improved technology for sensing and control that could help limit outages and their consequences -- not only those caused by a terrorist attack but also in the event of natural disasters.


"Power system disruptions experienced to date in the United States, be they from natural disasters or malfunctions, have had immense economic impacts," said M. Granger Morgan, professor and head of the department of engineering and public policy at Carnegie Mellon University, Pittsburgh, and chair of the committee that wrote the report.  "Considering that a systematically designed and executed terrorist attack could cause disruptions even more widespread and of longer duration, it is no stretch of the imagination to think that such attacks could produce damage costing hundreds of billions of dollars."


The report recommends ways to make the power delivery system less vulnerable to attacks, restore power faster after an attack or failure, and make critical social services less susceptible even if the delivery of conventional power is disrupted.  The report stresses the importance of investment in power system research, and notes that the level of actual investment in this research is currently much smaller than it should be.


High-voltage transformers are of particular concern because they are vulnerable both from within and from outside the substations where they are located.  These transformers are very large, difficult to move, often custom-built, and difficult to replace.  Most are no longer made in the United States, and the delivery time for new ones could run from months to years.  A promising solution, the report says, is to develop, manufacture, and stockpile a family of universal recovery transformers that would be smaller and easier to move.  They would be less efficient than those normally operated and would only be for temporary use, but they could drastically reduce delays in restoring disabled electric power systems.  In line with this recommendation, the U.S. Department of Homeland Security has recently cooperated with the U.S. power industry on the RecX program to develop and test a recovery transformer.


There are also critical systems -- communications, sensors, and controls -- that are potentially vulnerable to cyber attacks, whether through Internet connections or by direct penetration at remote sites.  Any telecommunication link that is even partially outside the control of the system operators could be an insecure pathway into operations and a threat to the grid.  Cyber security is best when connections with the outside world are eliminated, the report says.  When interconnections are unavoidable, high-quality technical and managerial security systems should be in place, including systems that monitor for and help avoid operator error or intentional sabotage.


The report states that although it is not reasonable to expect federal support for all local and regional planning efforts, DHS and/or the U.S. Department of Energy should initiate and fund several model demonstration assessments across cities, counties, and states.  These assessments should systematically examine a region's vulnerability to extended power outages and develop cost-effective strategies that can be adopted to reduce or eventually eliminate such vulnerabilities.  Building on the results of these model assessments, DHS should develop, test, and disseminate guidelines and tools to assist other cities, counties, states, and regions to conduct their own assessments and develop plans to reduce vulnerabilities to extended power outages.  To facilitate these activities, public policy and legal barriers to communication and collaborative planning will need to be addressed.


This report was completed by the National Research Council in the fall of 2007, but the sponsoring agency, the U.S. Department of Homeland Security, decided at that time that the report would be classified in its entirety.  After a formal request from the Research Council for an updated security classification review, the report was cleared for public release in fall 2012.  A foreword to the report, written by Ralph J. Cicerone, president of the National Academy of Sciences, and Charles M. Vest, president of the National Academy of Engineering, provides details about the delay and says that the key findings of the report remain "highly relevant."  The foreword states:


"We regret the long delay in approving this report for public release.  We understand the need to safeguard security information that may need to remain classified.  But openness is also required to accelerate the progress with current technology and implementation of research and development of new technology to better protect the nation from terrorism and other threats."


Concurrent with the report's release to the public, a workshop is being planned to address changes that have occurred since the report's completion in 2007 and where future efforts should be directed to improve grid resilience.


The study was sponsored by the U.S. Department of Homeland Security.  The National Academy of Sciences, National Academy of Engineering, Institute of Medicine, and National Research Council make up the National Academies.  They are private, independent nonprofit institutions that provide science, technology, and health policy advice under a congressional charter.  The Research Council is the principal operating agency of the National Academy of Sciences and the National Academy of Engineering.  For more information, visit  A committee roster follows.



Lorin Hancock, Media Relations Officer

Shaquanna Shields, Media Relations Assistant

Office of News and Public Information

202-334-2138; e-mail


Additional resources:

Report in Brief


Pre-publication copies of Terrorism and the Electric Power Delivery System are available from the National Academies Press; tel. 202-334-3313 or 1-800-624-6242 or on the Internet at  Reporters may obtain a copy from the Office of News and Public Information (contacts listed above).

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Division on Engineering and Physical Sciences

Board on Energy and Environmental Systems


Committee on Enhancing the Robustness and Resilience of Future Electrical Transmission and Distribution in the United States to Terrorist Attack


M. Granger Morgan1 (chair)

University Professor and Head

Department of Engineering and Public Policy

Carnegie Mellon University



Massoud Amin

HW Sweatt Chair in Technological Leadership,

CDTL Director, and Professor

Department of Electrical and Computer


University of Minnesota


Edward V. Badolato

President and CEO

Integrated Infrastructure Analytics Inc.

Falls Church, Va.


William O. Ball2

Senior Vice President

Transmission Planning and Operations
Southern Company Services Inc.
Birmingham, Ala.


Anjan Bose2

Regents Professor and Distinguished Professor of Electric Power Engineering

School of Electrical Engineering and

Computer Science

Washington State University



Clark W. Gellings


Electric Power Research Institute Inc.

Palo Alto, Calif.


Michehl R. Gent

President and CEO

North American Electric Reliability Council (retired)

San Diego, Calif.


Diane Munns

Vice President of Regulatory Relations and Energy Efficiency MidAmerican Energy Company

Des Moines, Iowa


Sharon L. Nelson

Former Chief
Consumer Protection Division
Washington State Attorney General's Office

David K. Owens

Executive Vice President, Business Operations
Edison Electric Institute
Washington, D.C.


Louis L. Rana

President and Chief Operating Officer
Consolidated Edison Company of New York (retired)
New York City


B. Don Russell Jr.2

Distinguished Professor, Regents Professor, and

Harry E. Bovay Chair

Department of Electrical Engineering

Texas A&M University

College Station


Richard E. Schuler

Graduate School Professor
School of Civil and Environmental Engineering
Cornell University
Ithaca, N.Y.


Phillip R. Sharp

Resources for the Future
Washington, D.C.


Carson W. Taylor2

Principal Engineer
Bonneville Power Administration (retired)
Portland, Ore.


Susan F. Tierney

Managing Principal
Analysis Group


Vijay Vittal2

Ira A. Fulton Chair Professor
Ira A. Fulton School of Engineering
Arizona State University


Paul C.Whitstock

Managing Director
Marsh USA Inc.
Washington, D.C.





Alan Crane

Study Director



1      Member, National Academy of Sciences

2      Member, National Academy of Engineering

?     Deceased