I recently received the following question regarding EMP effects: “What will happen to vehicles with electronic ignitions, a Chevy with an ignition module, but they are not hooked to a battery, with no path for electricity to follow, can it do damage? There may not be power on the grid, but what about a generator? Can a drill that was not plugged in still be able to run?”
The short answer is, maybe.
ONE SECOND AFTER
With regard to whether or not the electronic device is connected to the grid or sitting there not plugged in, makes some difference but is not necessarily a determining factor to the survivability of the device.
When the EMP (electro magnetic pulse) strikes, be it from a massive solar flare event, a nuclear explosion at altitude, an EMP bomb, or a focused EMP weapon, it does the same thing… emit a pulse of fairly broadband energy which radiates outward from the source.
This energy will radiate outward while losing strength as it travels further. Look up the ‘inverse-square law‘ for specifics. Knowing this, we can conclude that your electronic devices will be less likely damaged if you are much further away from the EMP source. The specifics of ‘how far away’ gets way too complicated for this article because there are many factors including the strength of EMP, how it was delivered, etc…
Some of the energy will be instantly induced into the power grid since most of our power lines are above the ground like a giant antenna and will soak up and distribute the pulse. Anything plugged in and in range will likely be zapped. Having said that, even if the electronic device is NOT plugged in, it will also be vulnerable to the effects of the EMP as the invisible pulse radiates outwards through the air, enveloping everything in its path (except for those items which are protected in a Faraday type cage or similar). Again, the degree of damage will depend on your proximity, and other factors.
‘Lights Out’ by Ted Koppel
By the way, a simple description of a Faraday cage is basically a box or container made of conductive metal or metal grids whereby the EMP current is induced in them rather than the circuits of the electronic devices being protected inside.
The reason why the device does not have to be plugged in to become damaged is because of what actually happens… The energy from the EMP pulse wave will 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, and as the invisible wave strikes it, it will fry (assuming sufficient strength and the other caveats…).
In conclusion, just know that ALL electronics are vulnerable unless specifically hardened against EMP (the military presumable does this, etc.) or protected via a purposed or natural Faraday cage. Also know that electronics are embedded in nearly everything that we use today. A major EMP would be the end of civilization as we know it. Will your Chevy stop running? Maybe. You would have to know the answers to questions like… How big is the EMP? Where are you located? What year is your Chevy? Will your drill stop working? Maybe. Does it have any electronic control in it other than its basic switch and coil winding? Will it matter if the power grid is down anyway? (power grid transformers will fry) Will your generator work? Maybe. All previous caveats and questions apply… Most all generators have electronic controlling circuits in them.
There are no clear answers to the questions at the beginning of this article. However in general, it may be safe to assume that nothing will work, and to plan ahead accordingly.
Related: 5 Nanoseconds To Lights Out