mented for other key equipment such as large bushings and circuit breakers, which could take many weeks to replace.

Utility restoration workers need adequate food, water, fuel for vehicles, and other essentials that may not otherwise be available during an extended outage. Communication networks also may degrade or fail in an extended outage, and it is essential that utilities have backup systems available that can be operated without grid power.

In addition, utilities and transmission operators should ensure that sufficient generating plants have black-start capability. This is provided by units that can be started with no offsite power available, a likely situation in a widespread blackout.

Reduce Vulnerability of Critical Services in the Event of Outages

Society is becoming ever more dependent on electric power. While system owners and operators should do all that they reasonably can to ensure that their systems are able to withstand anticipated assaults from natural and human sources, there are practical limits to how much these highly distributed systems can be hardened. Even without the threat of terrorism, there is a risk of occasional power outages, some of which will have large spatial scale and may last for many hours or even days. Terrorism increases the probable extent and duration of such outages and could cause them to occur at particularly inconvenient or damaging moments.

Since the complete elimination of all possible modes of failure is simply not feasible, an important design objective (in addition to resilience and the ability to rapidly restore the system after a problem occurs) should be the ability to sustain critical social services while an outage persists. Thus, in addition to strengthening the grid, society should also focus on identifying critical services and developing strategies to keep them operating in the event of power outages—be they accidental or the result of terrorist attack.

Strategies for managing an extended outage will require detailed planning and preparation to ensure that critical facilities can continue to operate, either from the remaining grid or from emergency power systems. Metropolitan areas with high demand and high reliance on transmission to deliver power from distant generating stations should be of particular concern in this regard. Critical facilities (such as hospitals) often have emergency backup power generation capability, but some of these are only intended to operate for several days. An extended outage could easily exhaust the supply of fuel. Many critical service providers have no emergency power at all.

Although it is not reasonable to expect federal support for all local and regional planning efforts, the Department of Homeland Security (DHS) and/or the DOE should each initiate and fund several model demonstration assessments at the level of 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, over time, 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 their vulnerabilities to extended power outages. To facilitate these activities, public policy and legal barriers to communication and collaborative planning will need to be addressed.

At a national level, DHS should perform, or assist other federal agencies to perform, additional systematic assessment of the vulnerability of national infrastructure, such as telecommunications and air traffic control, in the face of extended and widespread loss of electric power, and then develop and implement strategies to reduce or eliminate vulnerabilities. Part of this work should include an assessment of the available surge capacity for large mobile generation sources. Such an assessment should include an examination of the feasibility of utilizing alternative sources of temporary power generation to meet emergency generation requirements (as identified by state, territorial, and local governments, the private sector, and nongovernmental organizations) in the event of a large-scale power outage of long duration.

Government entities need to provide incentives (e.g., grants, fee-based awards, taxes, regulation) to support incremental costs associated with public and private sector risk prevention and mitigation efforts to reduce the societal impact of an extended grid outage. Such incentives could include incremental funding for those aspects of systems that provide a public good but no private benefit and the development and implementation of building codes or ordinances that require alternative or backup sources of electric power for key facilities.


There are many technologies and strategies that could be employed to make the power system more robust in the face of terrorist attack, make service restoration more timely after an attack, and continue the provision of critical services while the power is out. The best way to make needed changes affordable, and to develop new, even more effective and affordable approaches, is through research. Chapter 9 of this report discusses the current state of research for electric power, along with a set of recommendations for addressing research needs and developing related strategies.

The research that is needed to address the problems of terrorism is, for the most part, the same as the research that would address the broad problems faced by the transmission and distribution grid. The recovery transformer noted above is one of the few exceptions of terror-specific technologies that should be pursued. For example, the advanced computational system under development to improve control of flows on the grid also would be very useful in minimizing a cas-

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