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Comment by abeppu | Hacker News Reader

Maybe someone who knows a bunch about this stuff can enlighten me. I was kind of under the impression that a large solar flare would damage _all sorts_ of electronic equipment, by inducing currents wires all over the place.

- If we had extra transformers on hand, how would you protect them from also being damaged?

- If a solar flare is powerful enough to damage these transformers, would it also have damaged a large proportion of devices that use power? I.e. even if you could get the electric grid working, would there be working systems of any complexity to use the power?

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It is true that the solar flare will induce current in any exposed wire. However the following factors increase the current. The length of the wire, the thicker the wire, how poorly insulated it is, and the stronger the magnetic surges caused by the flare.

Long distance transmission lines are very long, fairly thick, and very exposed. The result is that the surges that they experience are several orders of magnitude stronger than, say, inside of your washing machine or a transformer unconnected to the wire. That surge doesn't hurt the wire, but it can blow the transformer when it hits it.

And hence the problem is mostly in blown transformers. If you have other transformers on hand, you swap them in and most of the system should be up.

I can see a couple of rather obvious problem with this. The electrical grid is, well, connected - the long, high-voltage sections are connected to the lower voltage sections which are connected to the even lower voltage sections. Those connections are through transformers, but if the surge is big enough to destroy even the largest transformers what's to stop it from blowing through all of the transformers and frying the delicate low-voltage control electronics of every grid connected device, including ones critical to operating the grid and power plants? Also, smaller devices are naturally going to be a lot more sensitive than huge transformers, so even if they don't experience the same level of voltage and current this could still be enough to destroy them.

Surge protectors

A bit more self-centered, is there a way to protect consumer devices from something this? I'm primarily thinking external hard drives with pictures/video we wouldn't want to lose. Maybe a faraday-cage-box of some sort we could buy to just store a spare external in?

Optical media is great for this. Too bad everything else about it sucks.

Your external hard drive that's disconnected from anything else should be OK. If there's a solar storm strong enough to fry that, you will have far far greater problems. Like whether you live or die. Caring about pictures and videos will be way way down on your list or priorities.

>If we had extra transformers on hand, how would you protect them from also being damaged?

Transmission cables are very very big antennas. Don't connect your spare transformer to that big antenna and it is perfectly safe.

I'm also not super knowledgeable in this area but let me have a shot:

* The transformers could be stored in a manner designed to keep them from being damaged by this event (off? physically disconnected? In large pieces?)

* I think things are surge protected at local levels so appliances would be fine.

Transformers are usually housed in metal boxes. Any wires inside metal sheeting of whatever geometry would be protected because any current induced would be induced in the metal container which dissipates the power of the pulse. To learn more read about Faraday cages.

Transformers are safe unless they are connected to cross country wires, which act as giant antennas, collecting energy from an EMP or a solar flare.

True, a transformer sitting in the middle of a warehouse is pretty safe. Unfortunately most of them actually in use have these huge current-carrying electrical wires running right that "faraday cage"...

Like they say in horror movies: "It's coming from outside the Faraday Cage".

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