How would an EMP affect our Nuclear Power Plants?
An EMP, or electromagnetic pulse, can be a potential threat to the United States and the world, that we are not prepared for. It can occur when a high-altitude nuclear weapon is detonated, or through severe space weather such as a solar flare or Coronal Mass Ejection. Even a lightening strike can produce an electromagnetic pulse, and interrupt transmission of power.
Although non-scheduled outages from power surges are usually transitory, the effect on power generation presents an unacceptable risk. The loss of supply not only cripples the end user but the generator of the power, as well. So, what happens when the transmission lines can not accept power from the producers, and how do the plants shut down under a station blackout condition? An EMP’s effect on the successful shutdown of a nuclear power plant must have consequences, so what are they?
Power Transmission and EMP
An EMP is caused by a high-intensity burst of electromagnetic energy and a rapid acceleration of charged particles. Through this burst, gamma rays collide with particles to produce free electrons which produce current (E1). It is this current that would destroy electronic equipment on Earth in the event of a severe solar storm, or an EMP attack.
A nuclear weapon detonation produces three waves, E1, E2,and E3. The third pulse, E3, is most like that of a solar event; the effect on the electromagnetic distortion in the Earth’s atmosphere. These longer-duration, lower-frequency pulses can ride the transmission lines and destroy unhardened transformers. The primary effect is to magnetize the cores of transformers connecting to the transmission lines, thus destroying their ability to step down or step up the power.
Today, with utility and non-utility power producers, transmission lines are connected over long distances, and regulated separately. By connecting the transmissions lines, transport of power becomes easier, but the vulnerability of a massive shutdown becomes a higher probability. A power surge from an EMP, an oversupply of voltage that can last up to 50 microseconds, has the capability to destroy transformers, shutting down power transmission and reducing a power plant’s output to zero. With a nuclear plant, this issue can become serious.