The electric power transmission and distribution system (the grid) is a critical and extraordinarily complex part of the nation’s infrastructure. The National Academy of Engineering called the grid the world’s largest integrated machine and a central part of the greatest engineering achievement of the 20th century-electrification of modern society. Reliable electricity service is essential to health, welfare, national security, communication, and commerce. Because of its scale, geographic reach, and complexity, however, the grid also poses many security challenges in maintaining reliable operation. Furthermore, more than 90 percent of the U.S. power grid is privately owned and regulated by the states, making it challenging for the federal government to address potential vulnerabilities to its operation, and perhaps especially its vulnerability to terrorist attack.
This report, prepared by a committee of dedicated experts assembled by the National Research Council (NRC), addresses those vulnerabilities and how they can be reduced. The committee began work in the fall of 2004 and completed it in the fall of 2007 with the intention of releasing the report by the end of that year. As required under the contract, the report was submitted to the sponsor, the Science and Technology Directorate of the Department of Homeland Security (DHS), for security classifcation review.
In August 2008, following protracted discussions regarding the information that would be suitable for public dissemination, DHS concluded that the report would be classified in its entirety under the original classification authority vested in the DHS undersecretary for science and technology. Because the committee believed that the report as submitted contained no restricted information, the NRC requested the formal classifcation guidance constituting the basis for the classification decision. That guidance was not provided, and so in August 2010, the NRC submitted a formal request for an updated security classification review. Finally, in August 2012, the current full report was approved for public release, reversing the original classification decision, except that several pages of information deemed classifed are available to readers who have the necessary security clearance.
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.
Even though the committee’s work was completed in 2007, the report’s key fndings remain highly relevant. We believe that we have a responsibility to make this report available to the public. Major cascading blackouts in the U.S. Southwest in 2011, and in India in 2012, underscore the need for the measures discussed in this report. The nation’s power grid is in urgent need of expansion and upgrading. Incorporating the technologies discussed in the report can greatly reduce the grid’s vulnerability to cascading failures, whether initi-