An Energy Central Expert Community Utility Security

Article Post

EMP: A Poorly Understood Threat

Grid security managers are experiencing growing concern over cyber security while another serious threat, electromagnetic pulse (EMP), has received very little attention. An electromagnetic pulse attack can have a devastating impact on the grid, rendering it useless perhaps for many years. While it is generally considered a low frequency/high consequence threat, recent developments regarding both human-caused EMP and the likelihood of geomagnetic storms significantly increase the chances of a major hit. Protective activity needs to be jump-started if appropriate measures are to be in place before it's too late.

The American public is poorly informed about this threat and therefore is making no demand on their utility companies to take action. Our state and national legislatures are equally uninformed so there is no serious allocation of funds to support utility preparation. The public, in ignorance, is not demanding anything from their legislators. Yet, time is becoming a critical factor. Some exceptions to the general inattention given to EMP are (1) Alaska has passed legislation to study the issue, and (2) the University of Maryland has given an R&D grant to Instant Access Networks LLC to develop EMP-hardened renewable energy systems.

The EMP threat is real and it comes from a number of different sources. An intentional attack can be launched by an adversary using a scud or ballistic missile to detonate a nuclear device high over the U.S. A scud can be launched from a ship offshore to detonate a nuclear device at an altitude of 25 to 40 miles, which would impact an area with a diameter of 200 to 300 miles. A ballistic missile could achieve an altitude of 300 miles. At that height, if centered over Kansas, a detonation would impact all three of our major grids. The attack, launched at sea with the ship quickly sunk, would not identify the adversary for a counterattack. An adversarial attack can therefore be launched without the fear of immediate retribution.

The level of devastation would be enormous. The nuclear blast emits a powerful pulse that strikes in three distinct portions, each with a different character. The first, called E1, has a high peak amplitude which radiates in less than one billionth of a second and couples effectively to all electronic systems regardless of size. It is too fast to be captured by lightning arrestors or other conventional protective devices. It mainly destroys electronic equipment including electronic protective equipment.

The second, E2, has lower amplitude and couples effectively through long lines to networked systems. Protective devices that would normally handle this portion will have been disabled by the first portion. It saturates the cores of both generators and transformers. The third portion, E3, hits the ground and creates a ground-induced current (GIC) which is slow and long-lasting. The GIC is called geomagnetic-induced current when solar-sourced due to the geomagnetic storm from which the pulse is derived. E3 is a largely DC component which offsets the AC waveform and couples with long power transmission lines that lead it right into transformers and generators, where it destroys the already saturated cores.

Solar storms present a major EMP threat. Also called "severe space weather", a major solar storm can wreak havoc on our grids. An example is the severe space weather event that hit the Hydro-Quebec power system in Canada in March, 1989. Automatic voltage compensation equipment failed, resulting in a voltage collapse. Five transmission lines from James Bay were tripped, causing a generation loss of 9,450 MW. With a load of about 21,350 MW, the system collapsed within seconds resulting in a nine-hour blackout for the Province of Quebec. During this same storm, a large step-up transformer failed at the Salem Nuclear Power Plant in New Jersey. There were about 200 less severe events reported in the North American power system.

The online Operations Manual of the North American Electric Reliability Corporation (NERC) cites geomagnetic storms of 1957, 1958, 1968, 1970, 1972, 1974, 1979, 1982, and 1989 as causes of major power system disturbances. However, "major" is a comparative term and may be inappropriate for those storms considering the destructive capability of the storms of 1859 and 1921. The former is the strongest ever recorded but the weaker 1921 storm was many times stronger than those cited by NERC. If a storm of that intensity were to occur during the increasing solar activity of the next few years, it would destroy most of the power equipment on our grids.

A National Research Council-sponsored workshop on the societal and economic impact of an EMP hit on our grids was held in February, 2008. It concluded that the consequences of a major storm would be catastrophic, dwarfing the damage from Hurricane Katrina and lasting 4 to 10 years. If we don't take steps to mitigate the impact, civilization as we know it would be destroyed. You can just imagine the consequences of instantly having no electricity across the nation for as long as 10 years.

It is truly remarkable how well our power systems have been improved by electronics to provide for much greater efficiency and safety. SCADA, as well as digital control systems and programmable logic controllers, have enhanced the operation and automation of power systems allowing for remote operation and the effective operation of very complex networks. This can be viewed as both a blessing and a curse, the latter due to the increased vulnerability of the network to EMP and other forms of electromagnetic interference.

The response to major blackouts over the past half century has been to develop protective methods and regulations that have helped to avoid many of the pitfalls of the past. Unfortunately, the damage from a nuclear blast or a massive solar storm cannot be averted with existing protective equipment. New devices and methods will be needed.

Two new factors are now playing a role in this complexity: the advent of the smart grid and the growing need for cyber security. Both are drawing the attention of grid security personnel, perhaps to the detriment of attention needed to develop better protection from EMP. The security component of the smart grid program is mainly oriented to protection from cyber crime as the expanded communication system needed for a smart grid opens up more opportunities for cyber attacks.

While electronics and microelectronics are omnipresent in today's grid environment, the smart grid will greatly increase their numbers. It will maximize the use of integrated circuits to manage every step from the generator to the consumer. If they are the first victims in a major EMP event, all of that investment would be for naught.

The potential for an EMP event is very real. The Commission to Assess the Threat to the United States from Electromagnetic Pulse (aka EMP Commission) has vividly described how our adversaries can fairly easily launch a nuclear attack for which our grid currently has no significant defense. (The report is available on the commission's website.) The capability of our adversaries to launch a deadly attack is constantly increasing while our capability to defend against such an attack is constantly decreasing. An EMP attack could also be at ground level from small, high-energy EMP generators with varying levels of capability. Another source could be an explosion of a chemical plant. While these local EMP strikes would not cripple the nation, they could still, through a cascade effect, endanger some millions of Americans at the regional level.

In the recently released Final Report of the Congressional Commission on the Strategic Posture of the United States, chaired by former Secretaries of Defense William J. Perry and James R. Schlesinger, there is the statement:


While efforts are underway to manufacture special grounding devices that could protect large generators and transformers from EMP damage, they are not yet ready for market. Also, there may be too little interest on the part of utility companies to devote financial resources to deploy them. The first step for utility security personnel is to study the potential for damage. A major EMP strike falls into the category of low frequency/high consequence and it is debatable how much should be spent when there is a relatively small chance that a major strike will occur. However, the consequences of a strike are so enormous that it cannot be ignored. Also, as the sun moves from a very quiet period to an energetic phase, due to peak in 2013, the chances of a less-than-major storm that would still cause considerable damage are much higher and the cost of protection less challenging. Grid security budgets will need to be enhanced to afford protective systems, both to counter the E1 portion that would damage electronics and to counter the stronger subsequent portions that would destroy generators and transformers.

Scientists are divided on the prospects for a major geomagnetic storm during the next active solar period. NOAA and NASA scientists are predicting a weak solar maximum in 2013 but this can be confusing as the great geomagnetic storm of 1859 occurred during a weak solar maximum.

The EMP threat has been very rarely mentioned in utility publications. Much more media exposure is needed. Grid security personnel, electric utility company executives, legislatures, government agencies, and the public at large need to learn about and appreciate the nature of this threat. They should start to learn about steps that can be taken at local, state, regional and national levels to mitigate this enormous potential for destruction. More emphasis needs to be placed on the development of local, protected renewable-energy generators which could provide at least a minimal power supply if the regional or national grid becomes dysfunctional.

Time is critical. Recent press reports show that North Korea is getting closer to a nuclear weapon and is actively developing its missile capability. The EMP Commission identified a number of potential sources that could launch an EMP attack. The next solar maximum is less than four years from now and the sun doesn't need to reach a solar maximum for a major geomagnetic storm to occur. Protective measures will take time to put into place. The time for action is now.

Explore Related Topics: