DG Development
Section 7. The Potential Benefits of Distributed Generation in Reducing Vulnerability of
the Electric System to Terrorism and
Providing Infrastructure Resilience
7.1
Summary and Overview
The United States electric power system is vast and complex. Thousands of miles of high-voltage cable serve millions of customers around the clock, 365 days per year. While the ready supply of electricity is often taken for granted, incidents such as the terrorist attacks on September 11, 2001, the Northeast Blackout of August 2003, and Hurricanes Katrina and Rita remind us how dependent we are on electricity and how fragile the grid can be. Water systems, pipelines, communications systems, transportation networks, emergency operations centers, and nearly every other category of critical infrastructure defined by the U.S. Department of Homeland Security (DHS) is in some way dependent on electricity. In this sense, electricity is the critical enabler of homeland security.
In addition to the vulnerability of critical infrastructure facilities resulting from their dependence on the primary electricity grid, these facilities most often rely on antiquated backup technologies as their sole source of electricity in an emergency—primarily diesel generators with limited staying power and only average power quality. If these backup generators prove incapable of meeting emergency power needs— as was the case during Hurricanes Katrina and Rita—the resilience of the entire network of critical infrastructure is in jeopardy at the very time when its resilience is most needed. Alternatively, if critical infrastructure facilities were to rely instead on primary and secondary power sources not exposed to these weaknesses, the entire system of critical infrastructure would be more resilient and thus more secure. The Energy Sector-Specific Plan of the U.S. Department of Homeland Security’s National Infrastructure Protection Plan (NIPP) notes that a healthy energy infrastructure is one of the defining characteristics of a modern global economy:
“It provides the lifeblood for commerce and is critical for our telecommunications, transportation, food and water supply, banking and finance, manufacturing, and public health systems. Any prolonged interruption of the supply of basic energy—be it electricity, natural gas, or petroleum products—would do considerable harm to the U.S. economy and the American people.”50
This section discusses 15 of 17 critical sectors of the U.S. economy, including as assessment of their vulnerability to terrorism and how DG can be a useful solution for reducing this vulnerability.
50 Interim Sector-Specific Plan, Energy Sector for Critical Infrastructure Protection, As Input to the National Infrastructure Protection Plan, Department of Energy, Redacted Draft, September 3, 2004. This is an Official Use Only plan that is currently not available to the public.
7.2
The Vulnerability of the Electric Grid and the Importance of Resilience
Protecting the nation’s electricity delivery system is a daunting task. The sheer size and extent of the system makes clear the difficulty of protecting it against both terrorism and natural disasters. Over 5,000 power plants (882 gigawatts of capacity produce 4,055 gigawatt-hours of electricity each year51), and
approximately 100,000 transformers, 63,000 substations and 160,000 miles of high-voltage transmission lines continuously direct electricity to 138 million customers across the country.
As stated in the NIPP:
“The key energy assurance challenges facing DOE are directly related to the energy sector’s complexity, diversity of ownership, and importance to all other critical infrastructure sectors. . . . DOE as the coordinating energy sector organization is not resourced to oversee the infrastructure protection of an infrastructure resource base valued in the trillions of dollars and absolutely critical to the welfare of the nation.”52
Energy sector stakeholders—both public and private—realize that tough choices need to be made in deciding how best to invest scarce security dollars to manage risk in the sector. However, careful investments in the right protective and enabling technologies can secure the grid against destabilizing failure.
The Homeland Security Advisory Council’s Critical Infrastructure Task Force recently recommended that the concept of “critical infrastructure resilience” (CIR) replace “critical infrastructure protection” (CIP) as the top-level strategic objective of the nation’s critical infrastructure security efforts (Homeland Security Advisory Council 2006).53 The Council defines resiliency as “the capability of a system to maintain its
functions and structure in the face of internal and external change and to degrade gracefully when it must.” In other words, resilient infrastructure systems will be less likely to collapse in the face of natural or manmade disruptions and will limit damage when disruptions do manage to inhibit the full
functionality of the system.
With critical infrastructure security focused on the concept of system resilience, rather than protection, the task of ensuring the nation’s infrastructure becomes more manageable and measurable:
“Critical Infrastructure Resilience is not a replacement for CIP, but rather an integrating objective designed to foster systems-level investment strategies. Adoption of CIR as the goal provides a readily quantifiable objective—identifying the time required to restore full functionality (Homeland Security Advisory Council 2006).”
51 Data for 2005 from the Energy Information Administration, accessed at http://www.eia.doe.gov/cneaf/electricity/epa/epates.html 52
Ibid at 35 and 56; for a review of the many challenges facing security stakeholders in the sector, see ibid at 35-36, 56-57, 75-76, and 96-98. 53 The Homeland Security Council is a high-level council comprised of leaders from state and local government, first responder communities,
7.3
The Benefits of Distributed Generation Technology and Systems in
Supplying Emergency Power
To address the vulnerabilities of the electric system to intentional disruptions, particularly those perpetrated by organized acts of terror, and to improve grid resilience, the National Research Council (NRC) of the National Academy of Sciences (NAS) recently recommended that “technology should be developed for an intelligent, adaptive power grid that combines a threat warning system with a distributed intelligent-agent system (NRC 2002).” Distributed generation can play an important role in such a system. In fact, the NRC points out:
“The trend over time has been to build large, remote generating plants, which require large, complex transmission systems. Today there is a growing interest in distributed generation – generators of a more modest size in close proximity to load centers. This trend may lead to a more flexible grid in which islanding to maintain key loads are easier to achieve. Improved security from distributed generation should be credited when planning the future of the grid (NRC 2002).”
DG can improve resilience through its reliance on larger numbers of smaller and more geographically disperse power plants, rather than large, central station power plants and bulk-power transmission facilities. Although larger numbers of smaller-scale power plants increases the number of targets for intentional attack, they reduce the number of customers who might potentially be affected. Electricity consumers are less vulnerable to supply disruptions when they have the ability to “island” themselves and thus to protect segments of the grid, particularly in critical infrastructure facilities such as fire and safety buildings, telecommunications systems, hospitals, and natural gas and oil delivery stations.
A simulated terrorist attack on California’s electric grid, which included a 25% reduction in power supplies, showed that recovery time would be about two weeks, at a direct cost to California’s economy of almost $11 billion. Much of these costs would have resulted from lost manufacturing output, and wholesale and retail trades. Greater DG by the electric utilities that serve these sectors, or by the sectors themselves, could lessen these economic impacts (ICF Consulting 2003).
In fact, research has shown that larger numbers of DG systems result in “potentially significant reliability advantages to increasing the amount of distributed generation in the system (Zerriffi 2004).”