A naked or near naked IC - such as a USB flash drive is likely to be impervious to any sort of EMP. Certainly nothing produced by a CME.
Electronic devices plugged into the mains, might see some nasty voltages, but one would really hope most would have enough protection that at worst only the power supplies fail.
Where problems come is that like lightning, CME’s and EMPs can create large DC currents, and this can saturate transformers, which essentially makes then cease functioning, and maybe fail. (Big transformers don’t fail nicely. There tends to be a lot of energy trying hard to get out really quickly.) So the entire grid can collapse, possibly taking some damage as it does. So we end up in a black start situation. That takes time to bootstrap out of, where time may be days.
A Faraday cage protects against electrostatic gradients. They don’t protect against magnetic effects. We are of course always talking about EM effects, so there is a crossover. For magnetics you start looking at very high mu metals, and much care in fabrication of the box.
If the wavelength of the EM is similar in size to defects in the Faraday cage - like holes - all bets are off. You could cut a slit in a metal box and discover that microwaves of the right frequency pass straight through. This about the time serious microwave engineers break out the sacrificial chickens.
How would large grid batteries fare in CME/EMP situations? I’m no electrical engineer, so my guess may be wrong, but I would expect them to be pretty much impervious to the effects. If anything, they could help reduce damage by absorbing much of the excess power that would be zinging around the grid.
The problem is that the power an CME drops onto the grid isn’t useful energy in any sense. See the recent thread on AC versus DC. It is about as useful as going into a cinema and shining a bright floodlight onto the screen. Sure the image is brighter, but not in a useful way.
If there was a substantial DC offset seen maybe a grid scale battery system could be constructed that could sink current from it. How much it would help is another matter. I’m dubious at best. The problem of DC currents would still exist, and their effect is what gets us into trouble.
Even it were useful, batteries can only adsorb energy at a rate dictated by their charge controllers. This is why you see grid scale batteries defined with two figures - one the total energy, the other the power delivery. So you might see a 100MWh, 50MW battery. It can deliver up to 50MW for two hours. This confuses the heck out of commentators, especially when the two numbers are the same - which is true for batteries sized to produce power for an hour.
We can reasonably assume the rate of power ingestion of a battery is much the same as its delivery. That puts a limit of what can be done.
The biggest value of grid scale batteries might be if enough of them are distributed about, we could partition the grid into safe sub-components and ride out the event and retain stability in the sub-grids. Resyncing and reconnecting them would be a whole lot easier if we had existing stability guarantees. Would likely still need to shed a substantial part of the load on the partitioned grids, but the outage might be much less disruptive.
I once spent several months building and repairing old faraday cages. A few things to keep in mind:
1.) If you have a gap, even a small one, it can perversely act as an antenna "broadcasting: the very signal you’re trying to block. A tear in your cage side can subvert it completely, and a door into in with imperfectly sealed edges can make it pretty much useless. That’s why the doors of mesh Faraday cages have springy phosphor-bronze “fingers” to prevent the appearance of slits in the cage exterior… Make sure your cage has no slits or rips in it. To test for these, I used to bring a radio and my cell phone into the cage. If you’ve got a good seal, your radio will give you only static and your phone will lose reception. It’s amazing how what appears to be a perfectly-sealed cage can leak EM waves like a sieve.
2.) Even better than simply having a small hole to pass your cables through is putiing a pipe or metal conduit whose length far exceeds its diameter through that hole. The long metal tube will block a lot of EM getting in. Make sure it’s electrically connected to the cage whgere it passes through, sand test by putting a radio and/or cell phone inside the cage.
A trash can would work well if you could guarantee that the place where the lid joins the top doesn’t have large semicircular gaps in it. And you can have what feels like a tight-fitting lid that will still have a gap. Again, test by putting a radio inside your trash can. If you still hear it, or you’re unsure, having a ring of springy mesh around the top might be a good way to prevent gaps.
Well, I don’t know about building my own Faraday Cage, but I just ordered a “power cleaning” surge protector to go with my new TV, which just happened to die last Wednesday evening. Yes, it was 7 years old, but it was working fine when, suddenly, the picture disappeared. I could hear the sound, change the channels, etc, but the TV was without any picture as if it was off. So, I’ll have that for my TV, and I have a UPS for my desktop computer. Is that good enough, or am I at the mercy of our moody sun which, to be honest, I am not in love with.
It sounds like one of the components that feeds the screen (the pixel drivers? The backlight?) failed.
We had a power surge one day. Just sitting watching TV, suddenly the audio amp started smoking. Assorted devices around the house died - the microwave, the controls for the fancy stove, the dishwasher, a few odd power bricks. Odd thing, many other devices were fine - the TV above the audio amp and DVD player beside it, the fridge, all our computers and phone chargers, TV in the bedroom, etc. In addition to replacing stuff, we also have a whole house surge suppressor hung off the braker panel in the basement now. I assume it wll stop most problems, but I doubt it’s rated for a nuclear blast.
My point before was that yes, a gap will leak radio waves, sufficient to allow a receiver inside to hear a broadcast signal. The question is, does an EMP work like light - will a small gap basically allow only a small amount of the full power in, thus reducing the risk of damage? (If so, would computers typically in incomplete metal cases be partly sheilded?) Plus, what’s the “frequency” of the pulse? Is it a single sharp peak (high Q?), or a spread that grows and disappears more gradually?
Unfortunately, tehere’s only one way to know for sure.
I remember in the early days of home computers, chips were incredibly sensitive to static and there were plenty of warnings about handling. Even today, many computer parts come in those silvered conductive(?) plastic bags. I wonder how effective those are as Faraday cages?
What is typical silvered car window tinting made of? Is it conductive? Many modern tall buildings, the windows are coated with metallic finishes for environmental purposes. (A few with gold on the windows). Obviously this is not enough to block cellular signals?
That entire gap between the door and the rest of the refrigerator, separated by that bead of insulating rubber, is a guaranteed antenna broadcasting into the interior.
What’s worse, the refrigerator itself, unless you’ve got one of those brushed stainless steel finishes, is covered with paint, so if you want to put some sort of mesh or phosphor-bronze springs to bridge that gap, you have to sand down through that paint coating to get electrical contact with the bare metal underneath.