Shooting at Tennessee Nuclear Power Plant Highlights Physical Vulnerability of U.S. Electricity System

Security of the nation’s electrical system from cyber attacks has received much attention as of late, but a recent event reminds us of the vulnerabilities in physical security. Last weekend, a security officer at Watts Bar nuclear power plant in eastern Tennessee exchanged gunfire with a man attempting to break into the facility.  When confronted, the man opened fire on the officer, and a gunfight ensued. The officer was not harmed, and the gunman fled the area after the exchange.

The FBI, Nuclear Regulatory Commission and local authorities are investigating the incident. The gunman remains at large.

While little information is known about the suspect, this incident demonstrates the physical security challenges posed by our electricity system. Nuclear facilities, of course, are particularly high profile targets that require a level of physical security far greater than that of other power plants. Nuclear facilities are required to have extensive security plans, and the response at the Watts Bar plant proved effective. But this event should serve as a reminder of the physical vulnerability of the U.S. electricity system writ large. The threat of a concentrated, coordinated attack is troubling and should not be ignored.

Reliance on centralized power plants and an outdated grid makes the electricity system vulnerable to terrorist attacks. A coordinated physical attack on several power plants and/or the grid itself could cause extensive and sustained power outages, which would have dire effects. According to Scott Pugh at the Department of Homeland Security, an attacker who understood vulnerabilities in the grid could use a “hunting rifle from a couple hundred yards away” to take out six key substations and “black out most of the U.S. east of the Mississippi.” And a more sophisticated attack, such as an electromagnetic pulse, could shut down large parts of U.S. electricity infrastructure for months. Food distribution, telecommunications, banking, heating/cooling systems, medical and safety infrastructure and security institutions (such as DoD installations) are all dependent on the grid and would struggle to function. Such an event would cause tremendous economic disruption and widespread chaos. Imagine the impacts of Hurricane Sandy, which caused over 8 million homes to lose power and necessitated 57,000 additional utility workers to restore it, but magnified many times over due to the targeted nature of an attack.

What might such an attack look like? A recently declassified National Research Council (NRC) report, originally commissioned by the Department of Homeland Security, discusses how a physical attack on older facilities could damage hardware that is difficult to replace. Specifically, high voltage transformers are exceptionally vulnerable and are often no longer built in the United States or are custom designed. There is little spare capacity of these transformers, so their destruction could be devastating to the grid. A coordinated attack on the grid and/or several large power plants (particularly those with less security than nuclear plants) could increase the stress on an already weak system and cause rolling blackouts that last for weeks or months, according to the NRC report.

The new energy era marks a fundamental shift in energy production in the United States, which includes increased reliance upon new sources of energy such as natural gas. As policymakers in the United States attempt to navigate this shifting energy landscape, they should choose to use the transition as an opportunity to improve the security of the entire electricity system at the same time. Some improvements to the physical security of the current system can happen immediately. Large, centralized power plants currently in operation, including non-nuclear facilities, should have strong security measures in place. Furthermore, increasing spare capacity and adopting more easily recoverable hardware could reduce the vulnerability of the grid system.

The new energy era also presents the opportunity to rethink how electricity is generated and distributed. The grid has not kept pace with improvements in computing technology, increased demand for electricity or the cyber threat. Prudent grid modernization and smart-grid technologies, combined with power sources with the potential for decentralization like natural gas, could facilitate fundamental changes to the electricity system and improve its resilience. This includes distributed generation, whereby small-scale, localized power generation feeds electricity into a more sophisticated grid structure that can respond to supply and demand in real time. A decentralized system reliant upon abundant, isolatable microgrids can serve as a safety net for localities, or critical infrastructure like DoD installations, in case the macro-grid comes under attack. While attacks on large power plants or the current grid structure could disrupt the entire electricity system, decentralized energy production spreads out the risk and makes the system significantly more resistant to sweeping disruptions.

As the United States shifts into a new energy era and develops new resources, coinciding improvements to the grid and cognizance of the importance of physical security could facilitate the development of a far more resilient and secure electricity system.

Photo courtesy Todd Plain and the United States Army.