American power companies are studying ways to protect electric grids against a high-altitude nuclear blast and other directed energy attacks that could severely disrupt electricity transmission, an industry representative told a Senate hearing Wednesday.
Scott Aaronson, managing director for cyber and infrastructure security at the Edison Electric Institute (EEI), stated in testimony that a consortium of U.S. electric companies is working with the Energy Department to study how to protect power grids from a nuclear blast-produced electromagnetic pulse attack or solar flares that could damage transformers and other electric components and shut down power for millions of Americans.
"There are a lot of threats to the grid … from squirrels to nation states," Aaronson said in testimony to the Senate Committee on Homeland Security and Governmental Affairs. "And frankly, there have been more blackouts as a result of squirrels [gnawing wire insulation] than there are from nation states."
The hearing was called to examine threats to critical infrastructure ranging from cyber attacks and criminal activities to terrorist sabotage and nation state nuclear attacks.
Aaronson, whose institute represents all investor-owned U.S. electric companies, said in testimony that electromagnetic pulse is a concern and could be caused by a high-altitude nuclear blast or a directed energy weapon.
The Electricity Subsector Coordinating Council, a group of chief executives from 21 electric companies and nine major industry associations, is working with the Energy Department to examine the threat. Aaronson, the council's secretary, stated that the threat study is based on research done by the Pentagon and national laboratories.
"This project is designed to enhance our understanding of system impact should such an attack occur and to explore the effectiveness of mitigation strategies, including hardening and recovery," Aaronson said in prepared testimony. "The project will allow grid-specific research to inform the application of technologies that will increase grid resilience and accelerate recovery."
The EMP research followed a Government Accountability Office study in March that urged greater efforts to deal with the threat of an EMP attack against the electric grid. The report said both the Energy Department and Department of Homeland Security should work more closely with electric companies on the problem.
The GAO report concluded that "DHS and DOE, in conjunction with industry, have not established a coordinated approach to identifying and implementing key risk management activities to address EMP risks."
EMP is the electric wave produced by nuclear blasts that is capable of knocking out electronics up to 1,000 miles away. The disruption could cause catastrophic damage and loss of life if power is not restored or backed up.
North Korea is one state said to be working on a a nuclear EMP attack capability, which would involve launching a long-range missile and detonating a nuclear device over the United States.
Iran could use EMP attacks if it successfully develops nuclear weapons in the future.
Russia and China have missiles and nuclear weapons capable of high-altitude detonation.
High-altitude EMP strikes are considered an attractive nuclear strike option because they would produce less blast damage and radiation than ground strikes. They also require less precise missile guidance systems.
The U.S. electric power system is made up of three grids—western, central and eastern—and is controlled by operational technology that security experts say is outdated and can be penetrated by hackers.
Aaronson did not say what steps should be taken to protect or harden the grid against EMP strikes. A fact sheet produced by the Edison Electric Institute states that shielding transformers for the entire grid system would cost $20 billion, 10 times what some advocates have estimated.
The fact sheet states that an attack with directed energy weapons would be difficult to carry out, requiring dozens of weapons detonated in coordinated attacks across the nation. "While not impossible, such a strategy is significantly more complicated to plan and carry out than claimed," the fact sheet says.
As for an EMP nuclear blast, the list of adversaries capable of such attacks is small and well known. Launching an overhead EMP burst would be "highly monitored by U.S. intelligence authorities and international organizations," the institute said.
"The best risk mitigation for an EMP event, especially one as severe as a high-altitude nuclear explosion, is prevention," the fact sheet says. "The prevention or preemption of such attacks is within the purview of the nation’s law enforcement, military, and intelligence functions."
Aaronson said the main threat to the electric grid is the disruption of the power transmission system involving some 35,000 substations that he described as a "soft target."
"The threats continue to evolve," he said.
Another vulnerability in the electric grid involves the 200 to 700 large power transformers that if damaged or destroyed would disrupt power for long periods.
Aaronson said that if these transformers were damaged by cyber or physical attacks or EMP, they could be replaced by stockpiled spare transformers.
In addition to the Spare Transformer Equipment Program, other methods can be used to share equipment in the event transformers are knocked out, he said.
Replacing a large transformer could take up to 18 months and would have to be procured from foreign suppliers, although Aaronson said that "under duress there are ways to procure transformers more quickly."
Electric grid vulnerabilities were highlighted by the Dec. 23 cyber attack against Ukraine’s power grid that left 700,000 people without power for six hours.
Aaronson said one of the lessons of the Ukraine grid attack was to shift away from remotely controlled equipment to manual operations.
"So this rush to automation is great because it gives us wonderful efficiencies. But it also increases the attack surface," he said.
Restoring power after an attack could involve operating power grids "sub-optimally" and prioritizing electricity to hospitals, first responders, and military installations.
Solar magnetic disturbances have impacted the electric power grid, specifically at high latitudes, but for negligible periods of time.
"It is inaccurate to say that a single geomagnetic disturbance would have a universal and unilateral impact across the entire grid,"
A group focused on the EMP threat, the Foundation for Resilient Societies, disagrees with Aaronson and the Edison Electric Institute on the EMP threat.
"The Edison Electric Institute in particular has opposed cost-effective protection against electromagnetic pulse," the foundation stated in a letter to the committee.
The foundation added that utilities are opposing efforts to harden the grid from EMP and other threats by opposing federal regulations that would require greater defenses.
Bill Harris, a Foundation for Resilient Societies board member, called Aaronson’s assertion that protecting grid hardware from EMP would be wasteful "a fallacy."
"Equipment to protect large power transformers costs about $350,000 per circuit, and protects transformers against voltage pulses via long transmission line connections during a solar storm or high altitude EMP explosion," Harris said.
Protecting 200 to 700 critical transformers would cost $80 million to $280 million and additional protection against solar storms would cost between $8 million and $28 million, Harris said.
"The combined cost would be about $1 dollar per person residing in the United States," he added. "Isn’t this a ‘best buy’ to prevent an enduring blackout that would risk loss of millions of lives and trillions of dollars in economic activity?"