Sun Spots Solar storms, like this one captured by NASA’s STEREO satellite, could knock out the power grid. NASA

It depends on the source of the pulse. Electromagnetic pulses (EMPs) large enough to cause you trouble come in two varieties: those produced by the sun, and those created by a nuclear bomb or another military-grade emitter device. With the sun-related variety, specifically coronal mass ejections (CMEs), your gear will probably be fine. But a really large CME could take down the power grid, says Bill Murtagh, the program coordinator of the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center. Power lines transmit electricity as an alternating current, but a pulse from a CME can introduce a direct current into the system, says Luke van der Zal, a technical executive at the nonprofit Electric Power Research Institute. This can cause transformers to overheat and work sluggishly, or fail altogether.

Despite the grid’s numerous built-in safeguards, if enough transformers go down, they could take large chunks of the grid with them. The only way to get it running again would be to replace all the damaged gear. CMEs aren’t usually disastrous, but the two largest blasts on record, which took place in 1859 and 1921, could each knock out the Northeast power grid if they happened today. On the bright side, although CMEs have been known to put satellites out of commission, our atmosphere deflects most of the energy, so the radiation is too diffuse by the time it reaches your electronics to destroy them.

A man-made EMP poses a greater threat. If one goes off in your neighborhood, there’s a significant risk that the concentrated pulse will induce extra voltage in the circuit-board components, frying them for good. The best bet for protecting your electronics is to store them in a Faraday cage: a cube of interweaving metals, preferably copper and quarter-inch-thick steel, which together can act as an electromagnetic shield. Like in a lightning rod, the copper attracts electricity while the steel absorbs magnetic pulses. A cage big enough to hold all your favorite gadgets—your cellphone, TV, computer, and so on—runs in the neighborhood of $15,000. An EMP could also crash the power grid, so you might want to spring for an extra cage to protect your generator too.

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18 Comments

Cool - so do I sit in the little cage and watch TV, work on my computer and talk on my phone???
I think a small safe for my 1tb backup drive makes a bit more sense. I can replace ALL my electronics for less than the cost of the cage.

marbaulo,

I understand where you are coming from, but if an EMP were to be unleashed there would be no place to get replacements; at least not within the affected area, which could be as large as half a continent.

seems like there is really no point in bothering with a faraday cage, as it sounds like you would have much bigger problems to worry about in the event of an EMP, like where to get a new face for the one that just melted off. but seriously, if it were to happen, replacement of damaged hardware would most likely be a moot point, like CasperSPT said,so just don't worry about it.

I guess military grade laptops come with a built-in cage.
anyone knows if this cage needs to be grounded in order to work, or it will stop EMPs anyway?

All "military grade" laptops are, our Panasonic Toughbooks. I should know I spent 6 years using them in the signal corp. The military likes to use what are called radhard chips "radiation hardened" they are supposed to help but not everything is radhard. And they don't always protect against EMP Look up "Actel" for more information on those guys. I wonder if it would be feasible to build a Faraday cage into the walls of your house. Sounds like a more reasonable investment. You don't necessarily have to worry about a nuclear event in your neighborhood. One could explode a bomb in out atmosphere and use it wipe out our electronics. Not so sure if the resulting fallout will make it to earth just some things I remember reading while in the army.

You COULD build a faraday cage into the walls of your house. Just don't expect your cell phone to work inside. Or your TV if you're not on cable or satellite. Or your cordless phone to work if you walk out to your garden while you're on a call...or anything that tries to transmit an RF signal through your walls, really.

If the hardware is not powered up it will not be affected. Therefore, always power down your equipment when not in use. If your PC is vital simply keep a backup PC in the closet and break it out if an event occurs. But the power grid will be down so you will need a generator. Then hope another one doesn't show up.

Voices1776,

Actually, EMP carries its own charge and can fry things even when they are disconnected. The cage would be the only way to really protect your electronics.

Also, wpmcg, as someone else mentioned earlier, the nuclear device if that is what is used can be detonated high in or just above the atmosphere so there would be little if any exposure to the blast or any fallout.

It would be a really bad deal.

How about roof-top photo-photovoltaic panels hooked into the grid? Can surges through the grid or the EMP's themselves damage them?

ha ha ha - wise up

Electrostatic discharge, ESD, caused by oneself is more likely to destroy your electronics than anything else.

A casual walk across a carpeted floor is all it takes to create enough static electricity to cause damage. Most internal electronics have what they call conformal coating that helps insulate it from the high voltage from a electrostatic discharge..

"Electrostatic discharge (ESD) is the sudden and momentary electric current that flows between two objects at different electrical potentials caused by direct contact or induced by an electrostatic field.[1] The term is usually used in the electronics and other industries to describe momentary unwanted currents that may cause damage to electronic equipment."

www.en.wikipedia.org/wiki/Electrostatic_discharge

Ron Bennett

>How about roof-top photo-photovoltaic panels hooked into the grid? Can surges through the grid or the EMP's themselves damage them?

I'm guessing it'd fry the inverter if not the panels, too.

Anyone remember seeing those little police car-launched devices that speed under the car they were chasing and then set off a small EMP to disable the car? That was a few years ago and I doubt they ever used it outside of trials due to safety concerns, but it was pretty cool. I'd like to build one of those for the idiots with fart pipes on their cars.

is this similar to the movie matrix?

That's just a bit much. What are the actual chances that either of these two event could happen? That makes all the difference.

15K for a farday cage? HA! I dont think so.

Actual chances I would say... in the neighborhood of 100%, cyber-terrorism and the like will happen one day.

I dont need a big $15,000 cage to store my pc/etc. in though, just include the mesh in your siding/roof/etc. and have smaller, more focused cages around your toys. An RF repeater my be used, but then it needs a bandwidth filter, etc. and every hole in the cage is a weakness... wonder why people arent doing this already huh?

Just making a small one yourself for your external hdd etc. is a good idea, I plan on doing that myself.. same principle as the creditcard sleeves, but what are you going to use your undamaged hdd with when all the other electronics in your house fry, and in your car?

Very bad deal indeed.

Do we need to worry about EMP and the fact that it impacts the brains decision to decipher right from wrong? Is there really something else behind the strings of violence and murder we are seeing these days?

EMP is essentially a fast AC wave of magnetic force that induces a high voltage into any nearby wires, much as a magnetic induces electricity. Military equipment is hardened by using twisted shielded pairs of wires, RF chokes, and Zener diodes to prevent over voltage. In today's world with everything being electronic,nearly everything would be rendered useless. Cars, radios, computers. If you were to store a backup radio in a Faraday cage ( essentially a conductive box), there wouldn't be anything to listen to after the event, as the radio and tv stations would be down too. Phone of today are electronic, so they'd be gone. Trucks? I don't know if old trucks might still run, those that had electric as opposed t electronic ignition. Could be very bleak indeed.

Actually, EMP carries its own charge and can fry things even when they are disconnected. The cage would be the only way to really protect your electronics. Also, wpmcg, as someone else mentioned earlier, the nuclear device if that is what is used can be detonated high in or just above the atmosphere so there would be little if any exposure to the blast or any fallout. It would be a really bad deal.
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