Will an EMP Destroy Electronics That Aren’t Plugged In?
Someone asked the following questions. “Can an EMP (electromagnetic pulse) destroy electronic devices if it’s not plugged in?” “What if it’s battery powered, and turned off, will an EMP still destroy the electronics inside?”
In my opinion, the short answer is, maybe, or I would lean towards – probably. I know that’s not what you wanted to hear. You’re looking for a yes or no answer. However, it depends…
If you’re reading this right now, it means you’re concerned about the after effects of an EMP. I suggest that you read the following best selling novel. It exemplifies what might happen to society after an EMP. I guarantee it will motivate you into action:
Will an EMP Destroy Electronics?
The short answer is it depends.
An electromagnetic pulse can damage electronics by inducing high voltage into circuits. Devices connected to long conductors (such as power lines, antennas, or charging cables) are generally much more vulnerable because those wires act like antennas that collect the energy.
Small electronics that are not plugged into anything may have a better chance of surviving, especially if they are not connected to long wires. However, a sufficiently strong EMP field could still damage internal semiconductor components.
The most reliable protection from an EMP is shielding sensitive electronics inside a properly designed Faraday cage.
What to put in a Faraday Cage?
It’s not a sole determining factor. Plugged in or not. It makes some difference. But it’s not necessarily a sole determining factor to the survivability of the electronic device. When the EMP (electromagnetic pulse) strikes, be it from a massive solar flare event (CME, coronal mass ejection), or a nuclear explosion at altitude (an EMP bomb), it does a similar thing… Emit a broadband pulse of high energy (volts per meter) which radiates outward from the source.
EMP Risk to Electronics
| Device Type | Vulnerability to EMP |
|---|---|
| Devices plugged into the power grid | Very High |
| Devices connected to long antennas or cables | High |
| Small battery-powered electronics | Moderate to Low |
| Electronics inside a Faraday cage | Very Low |
ONE SECOND AFTER
(view on Amazon)
CME from the Sun, and Man-made EMP
A CME from the sun will be a fairly long duration event. Hours. The CME’s electromagnetic energy will interact and induce voltage and current into power lines above ground (the electric grid). And anything acting as an electrical conductor. One factor is the longer the conductor/antenna, the more induction of the radiated energy.
Whereas a man-made nuclear EMP is a very short duration event – although it produces a massive high voltage broadband pulse. We’re talking in the range of 50,000+ volts per meter. An extremely short time duration of only nanoseconds.
This energy will radiate outward while losing some strength as it travels further away from its source. You might look up the ‘inverse-square law‘ for specifics. Knowing this, we can conclude the following… The further away from the EMP source, the less potential damage. Though we’re talking long distances here – assuming a high altitude EMP detonation.
How far away? The specifics are complicated. Beyond the scope of this article. There are many factors. EMP strength. Its delivery. And others. For the sake of generalization, I would speculate the following… Your electronics are much safer being ~ 1,000 miles away from a man-made high altitude EMP compared with only a few hundred miles.
However, the effects from a solar CME are different. The earth’s atmosphere and power grids interact with the CME energy during its many hours of duration. This has the potential to affect everyone.
Some of the EMP energy (from CME, or, high altitude EMP detonation) will be instantly induced into the power grid. Most of our power lines are above the ground. They behave like a giant antenna. The grid will soak up and distribute the pulse.
Important distinction: A solar CME and a nuclear EMP affect electronics differently. A CME primarily induces currents in very long conductors such as power transmission lines, pipelines, and large electrical infrastructure. Smaller standalone electronics that are not connected to long wires are generally less affected. A high-altitude nuclear EMP, however, can induce damaging voltages in shorter conductors and even directly within electronic circuits depending on the field strength and proximity to the event.
EMP Electronic Destruction – Plugged in versus Not Plugged in
Plugged in, and in range? Probably zapped. Most of our electric power grid is above ground. It will quickly absorb the EMP (or the longer duration ebb and flow from a CME). This will near instantly distribute throughout the affected portion of the grid. The result? Wide spread electronics destruction. Plugged in? More vulnerable.
Not plugged in certainly has an advantage, since long wires such as power cords and antennas can act like antennas that collect EMP energy.
Testing conducted for the EMP Commission suggested that many small consumer electronics survive EMP exposure unless connected to long conductors.
Battery operated? Turned off? (Doesn’t matter one way or the other if it’s on or off via battery) Here’s what matters most… Strength of EMP field at its location.
Even if the electronic device is NOT plugged in, it will still be vulnerable to the effects of EMP. The invisible high voltage pulse. It radiates outwards through the air. It envelopes everything in its path. Except for those items which are protected in a Faraday cage. The energy from the EMP pulse wave may melt down the transistor ‘junctions’ within semiconductor electronics.
You could have a portable shortwave radio sitting on your desk, not plugged into anything at all. As the invisible wave strikes it, it may fry (assuming sufficient EMP strength and the other caveats…). Again, the degree of damage will depend on your proximity, and other factors.
Ted Koppel gets in-depth regarding America’s EMP threat:
Lights Out, A Nation Unprepared, Surviving the Aftermath
(Amazon)
The Faraday Cage
By the way, a simple description of a Faraday cage. It’s basically a containment with an exterior comprising a conductive material (e.g. metal or conductive screen, etc.). A Faraday cage shields the interior from an external charge or electromagnetic radiation to an extent depending on its design.
Faraday cage effectiveness? It’s defined by the following… The cages design. And choice of construction materials. All Faraday cages take electrostatic charges, or even certain types of electromagnetic radiation, and distribute them around the exterior of the cage. Thus, protecting whatever is inside – within the limitations of its design.
Will an EMP Destroy Cars?
Many people also wonder whether an electromagnetic pulse would disable automobiles.
Modern vehicles contain dozens of electronic control modules, sensors, and computers. Because of this, some people assume that all vehicles would instantly stop working after an EMP. In reality, the answer is more complicated.
Testing conducted for the U.S. EMP Commission suggested that many vehicles would continue operating, especially if they were not connected to long external conductors. Some vehicles experienced temporary disruptions, while others stalled but were able to restart.
As with other electronics, the outcome would depend on several factors:
- Strength of the EMP field
- Distance from the source
- Vehicle design and shielding
- Length of connected wiring acting as antennas
While some or many vehicles might be affected, it is unlikely that every car on the road would instantly stop. That is the practical reality.
FAQ: EMP and Electronics
Turning a device off does not necessarily protect it. If the electromagnetic field is strong enough, damaging voltages can still be induced in circuits.
Unplugged electronics are generally less vulnerable than devices connected to long wires, but they are not guaranteed to survive.
Solar panels themselves are relatively robust, but connected electronics such as inverters and charge controllers may be vulnerable.
In conclusion, just know that ALL electronics are vulnerable to EMP / CME. That is, unless specifically hardened against EMP or protected via a purpose-built Faraday cage. Electronics. They’re embedded in nearly everything we use today.
A major EMP would be the end of civilization as we know it.
There are no clear answers to the questions at the beginning of this article. However, in general, it may be safe to assume this… Electronics Armageddon. So, plan ahead accordingly.
[ Read: 5 Nanoseconds To Lights Out ]
[ Read: Nuclear EMP Components E1, E2, E3, and what they mean… ]
The answer is yes something not plugged in would be destroyed and you have no business writing an article on the it if you don’t even know the answer to such a simple question. The CME is the power that’s toasting everything goofy if don’t need to be plugged in!
Thanks for the article, Ken. Frankly, we really don’t have any modern experience to prove or disprove whether all electronics will be fried as a result of an EMP from a nuclear bomb.
My grandfather participated in the atomic bomb explosions conducted on the Bikini Atoll. He was the Captain of a support ship during the testing. No disruptions were reported of aircraft or naval ships. Of course, this was in 1946 and “electronics” was in it’s infancy.
However, by 1945, the ENIAC, the first programmable, electronic, general-purpose digital computer, was completed for the U.S. Army to calculate artillery firing tables. So there were electronic devices being introduced in the military. I’m just not sure if they were anywhere near the Bikini Atoll.
I’ve often wondered about the range of electromagnetic pulses and how they might dissipate over distance.
I first read “Alas Babylon”, by Pat Frank, as a teenager. Forstchen’s book is pretty stark and references Frank’s book. There are a multitude of post-apocalyptic books written in the last 10 or 15 years. They have been converted to audio books. All seem to have the same pattern established first by Frank and then by Forstchen. Which is: EMP shuts down the entire grid. All modern cars are dead on the road. People turn barbaric. Bad guys do really bad things. Heros or anti-heros fight back. The stories end with a question.