# EMP, power systems and fuses **URL:** \ **Category:** Cecil's Columns/Staff Reports\ **Created:** [July 6, 2012, 12:02pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412 "2012-07-06T12:02:49Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![gotpasswords](https://avatars.discourse-cdn.com/v4/letter/g/c57346/32.png) [@gotpasswords](https://boards.straightdope.com/u/gotpasswords)\ **Post date:** [July 6, 2012, 12:02pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/1 "2012-07-06T12:02:49Z")
In [today’s column about EMP](http://www.straightdope.com/columns/read/3060/could-an-electromagnetic-pulse-disrupt-civilization) it was noted that some things such as high-voltage transformers are not exactly stockpiled in abundance and that re-creating them would take some time. Would this delay bringing power systems back up after being damaged by an EMP? Sure, but… Would an EMP really turn every transformer into a smoldering lump? Or would an EMP just blow out the weak spots in the system? What weak spots? Oh, how about the \*intentionally \*weak spots known as fuses? Granted, the task of having to replace thousands of fuses would take a good while, but we probably have more fuses on hand than transformers, and in a dire emergency, fuses can be bypassed. ---
**Author:** ![davekhps](https://avatars.discourse-cdn.com/v4/letter/d/a5b964/32.png) [@davekhps](https://boards.straightdope.com/u/davekhps)\ **Post date:** [July 6, 2012, 2:21pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/2 "2012-07-06T14:21:11Z")
The two largest problems with EMP, in my mind, are these: 1. The system is only as strong as the weakest link. Meaning, \*so what \*if the “entire” grid isn’t brought down? Bring _enough_ of it down, all at once, and you’re left in a “close enough for golf” situation. We had one one-hour storm here in the D.C. area and people were out of power for days. Replicate this on the entire Eastern seaboard but make it effect _every_ element of the grid all at once-- and things not on the grid, like vehicles, gas generators, you name it-- and then see how quickly the system can come back. 1. EMP is a wonderfully assymetric threat. Meaning, even a backwards country like North Korea can “fight above its weight” as long as it has the means to do so. You don’t need a thousand warheads incinerating America to bring it down a bunch of pegs-- you only need a few. Crazy act of war, sure; but far more obtainable than the Cold War-era MAD-level arsenals were. Anyway, my guess is that an EMP attack would be Very Bad News. No, we wouldn’t be propelled back into the Stone Age, and no, we wouldn’t spend forever dealing with the problem. The concern is, however, that we’d spend _long enough_ dealing with the problem that the second- and third-order effects would be nigh catastrophic-- modern civilization can put up with major urban blackouts in a single metro area for a week at a time with just relatively minor kvetching, but try doing that on a massive geographical scale for _months_ at a time, where _no_ electrical stuff works, not just the power plug. A modern 21st century society hasn’t had to deal with that kind of shock. No one can say for sure how, let alone if, it could cope with that. ---
**Author:** ![gnoitall](https://avatars.discourse-cdn.com/v4/letter/g/bb73d2/32.png) [@gnoitall](https://boards.straightdope.com/u/gnoitall)\ **Post date:** [July 6, 2012, 2:23pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/3 "2012-07-06T14:23:16Z")
> [@gotpasswords](#): > > In [today’s column about EMP](http://www.straightdope.com/columns/read/3060/could-an-electromagnetic-pulse-disrupt-civilization) it was noted that some things such as high-voltage transformers are not exactly stockpiled in abundance and that re-creating them would take some time. Would this delay bringing power systems back up after being damaged by an EMP? Sure, but… > > Would an EMP really turn every transformer into a smoldering lump? Or would an EMP just blow out the weak spots in the system? What weak spots? Oh, how about the \*intentionally \*weak spots known as fuses? Granted, the task of having to replace thousands of fuses would take a good while, but we probably have more fuses on hand than transformers, and in a dire emergency, fuses can be bypassed. Ancient Chinese Electrical Engineer Adage: A $50 transistor (or $500,000 transformer) will happily sacrifice its life to save a 5-cent fuse. More to the point, fuses can’t save a transformer if the electromagnetic pulse induces destructive voltages directly within the coils of the transformer itself, which is how that actually happens. ---
**Author:** ![Una\_Persson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/una_persson/32/346_2.png) [@Una\_Persson](https://boards.straightdope.com/u/Una_Persson)\ **Post date:** [July 6, 2012, 2:27pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/4 "2012-07-06T14:27:05Z")
> [@gnoitall](#): > > Ancient Chinese Electrical Engineer Adage: A $50 transistor (or $500,000 transformer) will happily sacrifice its life to save a 5-cent fuse. I love this quote. ---
**Author:** ![chappachula](https://avatars.discourse-cdn.com/v4/letter/c/d2c977/32.png) [@chappachula](https://boards.straightdope.com/u/chappachula)\ **Post date:** [July 6, 2012, 2:30pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/5 "2012-07-06T14:30:45Z")
> [@gotpasswords](#): > > Would an EMP really turn every transformer into a smoldering lump? . but we probably have more fuses on hand . Well let’s see what one source says: A solar storm as powerful as the one in 1859 > [@](#): > > “could fry more transformers than the power companies keep stockpiled, leaving millions without light, potable water, sewage treatment, heating, airconditioning, fuel. phone service,or perishable food and medicine during the months it would take to manufacture new transformers.” This is not from the National Enquirer or the Daily Sun It is from National Georgrahic Magazine.(The most recent issue-June 2012, page 42.The cover article is about solar storms.) Now, Natl Geo is a not a peer-reviewed science journal…but it’s a pretty respectable publication that definitely does not aim for “woo” appeal. Maybe we should be a little more seriously concerned with the physical reality of Mother Nature, and less with Cecil’s cynical bashing of Newt. ---
**Author:** ![chappachula](https://avatars.discourse-cdn.com/v4/letter/c/d2c977/32.png) [@chappachula](https://boards.straightdope.com/u/chappachula)\ **Post date:** [July 6, 2012, 2:36pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/6 "2012-07-06T14:36:37Z")
(deleted a double post. Sorry). I was just trying to correct a typo in my previous post: I meant “National Geographic” Magazine ---
**Author:** ![Irishman](https://avatars.discourse-cdn.com/v4/letter/i/b487fb/32.png) [@Irishman](https://boards.straightdope.com/u/Irishman)\ **Post date:** [July 6, 2012, 3:03pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/7 "2012-07-06T15:03:39Z")
We have a national magazine by and for Georges? 😉 ---
**Author:** ![ftg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ftg/32/2801_2.png) [@ftg](https://boards.straightdope.com/u/ftg)\ **Post date:** [July 6, 2012, 5:19pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/8 "2012-07-06T17:19:48Z")
How long is it going to take to manufacture all the replacement parts to get basic services going again? That is going to be difficult and then some. Given that: 1. The plants themselves are going to be down. A really tricky bootstrap process. And too many core parts are not easily orderable from overseas. 2. There are going to hordes of hungry, angry people roaming around causing problems. Once the food runs out in the cities, rebuilding stuff is going to get really, really hard. Moving and processing food will be the main bottleneck. And even if you could get bags of flour to people, how many are going to know how to and be able to do anything with it? Even if we got lucky and got basic things running in 2 years, that’s about 1.9 years too long to keep society stable. It’s pretty much your standard movie apocalypse if this ever happens. ---
**Author:** ![davekhps](https://avatars.discourse-cdn.com/v4/letter/d/a5b964/32.png) [@davekhps](https://boards.straightdope.com/u/davekhps)\ **Post date:** [July 6, 2012, 6:44pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/9 "2012-07-06T18:44:35Z")
> [@ftg](#): > > Even if we got lucky and got basic things running in 2 years, that’s about 1.9 years too long to keep society stable. > > It’s pretty much your standard movie apocalypse if this ever happens. This. Even if the infrastructure to rebuild remains intact, supporting and exploiting that infrastructure is going to be one heckuva challenge. Meaning, even if you could build replacement equipment-- no sure thing-- you no longer have the modern support infrastructure in place to distribute, install, maintain, etc. We live in a “just in time” society. An EMP eliminates the “just in time” part-- what then happens to that society? Again, it’s one thing to hunker down for days (storms, power failures), or even weeks (epidemiological crises). But we’re talking months at a minimum. EMP is a nasty thing. I’d almost rather have traditional nuclear war-- at least then there’s no worry about the aftermath, we’d all be screwed. ---
**Author:** ![Michael63129](https://avatars.discourse-cdn.com/v4/letter/m/3da27b/32.png) [@Michael63129](https://boards.straightdope.com/u/Michael63129)\ **Post date:** [July 6, 2012, 7:19pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/10 "2012-07-06T19:19:49Z")
Fuses won’t work if the induced voltages are high enough; the current will just arc across the gap, which would especially be a concern with long-distance transmission lines. Although I would think that an isolated transformer (e.g. a spare just sitting there) wouldn’t be damaged since there isn’t much space for current to be induced (longer lines = more voltage and current induced; note also that it is current more than voltage that causes damage). ---
**Author:** ![Fool\_in\_the\_Rain](https://avatars.discourse-cdn.com/v4/letter/f/8491ac/32.png) [@Fool\_in\_the\_Rain](https://boards.straightdope.com/u/Fool_in_the_Rain)\ **Post date:** [July 6, 2012, 7:28pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/11 "2012-07-06T19:28:26Z")
Working for a utility, I can tell you the electrical infrastructure it is a lot more delicate then it first appears. I’ve been involved in many storm restorations and it still amazes me to this day how simple it is to cause a power failure. It takes approximately 3-6 months to order and have delivered any transformer over the size of 3000kva. Granted we have ‘some in supply’, but obviously not enough to replace all of them in the system we own. Fuses can be bypassed, sure, but it puts the system following the fuse in danger of overload, _especially_ people’s homes/businesses. Another problem is incorrectly installed generators that can back-feed into the system, overloading it in that way. How easy is it to have a system failure: The Great Northeast Blackout of 1965 all began when a relay (about the size of a fist) failed, diverted electricity through other feeders, overloading them, which in turn forced other systems to ‘dump’ their power to other feeders, causing massive back-feed and overloading them, until the entire system simply collapsed, and was forced to be shut down. Time to system failure ~ 5 minutes. Southern New England, New York State and southern Quebec were out for up to 12 hours Cause: Human error - relay settings were set too low. ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [July 7, 2012, 1:34am UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/12 "2012-07-07T01:34:26Z")
This whole thread, OP included, is ALL off-topic! Cecil’s above-cited EMP column was itself a follow-up on his earlier 1993 column, in which Jonathan Jensen of Baltimore simply asked: [Is there a way to silence those Og-damn obnoxious boom-cars](http://www.straightdope.com/columns/read/781/is-there-a-way-to-permanently-silence-somebodys-loud-car-stereo)? In that earlier column, Cecil promptly went off-topic, writing about large-scale EMP events that take massive energy bursts (like nuclear blasts or sun storms), whereupon they take out a whole city like Honolulu from 800 miles away. Hardly likely your average city-dwelling peace-and-quiet-loving citizen is going to have access to that. All’s that Jonathan Jensen ever wanted was some small-scale weapon that one person could wield to take out that Og-damn boom-car from, say, across the street. And that’s all I want too, and I’m still waiting for Cecil, or someone, to expound on that. Forget global EMP’s that fry our transformers back to the stone age. I still just want a way to shut down those boom-cars! It took a response from B. J. Merholz of Los Angeles to point out the discrepancy in Cecil’s response: > [@](#): > > Your reply referred to something like nuclear bombs or cosmic forces or some other sad expression of comic overkill rather than taking your correspondent’s question seriously and answering it accordingly. You could have advised the gentleman that several such devices have already been invented and are already available on the open market. One good example is the very handy Smith and Wesson .38 caliber Police Special. Dang it, I (like Mr. Merholz) just want a small-scale personal boom-car silencer, capable of operating on one vehicle at at time, at a range of, say, 0.25 mile or less. THAT was the real OP of this discussion! And Cecil goes off the deep end with his EMP talk which, interesting though it may be, doesn’t help. ETA: I mean, I want something high-tech and electronic and more subtle than the suggested Smith and Wesson anti-boom-car device. ---
**Author:** ![Hagen](https://avatars.discourse-cdn.com/v4/letter/h/45deac/32.png) [@Hagen](https://boards.straightdope.com/u/Hagen)\ **Post date:** [July 7, 2012, 2:14pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/13 "2012-07-07T14:14:56Z")
@Senegoid Google has come up with this: [3 Ways to Build an EMP Generator - wikiHow](http://m.wikihow.com/Build-an-Emp-Generator) However, here’s what I’d prefer to use and I know that it would work: [Giant Vortex Cannon - YouTube](http://www.youtube.com/watch?v=QrgTtZXuj4w&feature=youtube_gdata_player) Explosively fired vortex ring generator. No way he going to be able to trace it back to you. Just blow the car into a tree. Other little known facts about google is that it takes just as long to find what you’re looking for as it does to write a complaint message. YouTube is also good for this 🙂 I’ve heard that the great majority of our infrastructure was specifically protected from emp during the cold war, but that this is not the case anymore because we no longer consider it as likely. I am cynical about the statement that cold-war era infrastructure was specially hardened on a large scale. On that note: how do you harden your infrastructure on a large scale? Decentralize it? Insulate it? ---
**Author:** ![Heracles](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/heracles/32/487_2.png) [@Heracles](https://boards.straightdope.com/u/Heracles)\ **Post date:** [July 7, 2012, 3:07pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/14 "2012-07-07T15:07:41Z")
What is not clear to me is what parts of electronics will fail. Is the individual transistor fried? Or does it just malfunction for a few seconds, which means the surrouding circuits are overloaded or submitted to currents, voltages, stresses they’re not designed to handle, which quickly fries out capacitors and such? One thing that hasn’t been mentioned up to now is that, once people have their food and shelter back, they still won’t have a job. If electronics became inoperable tomorrow morning, I as a programmer wouldn’t have anything to do, and neither would most office workers. As has been demonstrated in recent years, it’s difficult to keep an economy afloat without workers. A few other aspects to consider: - Individual money is mostly in electronic form, to the point where many people don’t even have paper proof of their financial assets. Yes, all banks have remote backup sites for their computing infrastructure, and presumably so do the NYSE and NASDAQ, but these are co-location services which are not designed to host all institutions at the same time. And there’s no point having a backup computer center on the other coast if the long-distance communications networks don’t work. - Speaking of communications, how much long-distance phone service is still analog? 0%? - If hard drives and magnetic tapes get damaged or erased (would they?), even the backups are fried. Better archive your stuff to DVD, people! - Landline phones, for those who still have them, are mostly cordless electronic gizmos themselves. Old ladies would get burglarised for their Model 500 rotary-dial phones. Oh, and their electro-mechanical washing machines, ovens, refrigerators, etc. And their phone books. ---
**Author:** ![Iggy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/iggy/32/3364_2.png) [@Iggy](https://boards.straightdope.com/u/Iggy)\ **Post date:** [July 7, 2012, 4:54pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/15 "2012-07-07T16:54:34Z")
More than just transformers, we don’t even have enough utility poles stockpiled for even a modestly widespread disruption. In 2004 four hurricanes hit the state of Florida in short succession. One of those, Ivan, had laid waste to the island of Grand Cayman on its way to the Florida panhandle. Power companies were scrounging power poles and transformers to rebuild downed systems. Much of Grand Cayman was without power for two months. Power was only restored that soon because Fortis, the parent company of the Cayman power company, already had assembled in Canada a shipment of power poles destined for their operations in Belize to build out new systems there. The shipment was diverted to Cayman. Without that shipment it would have been a few more months to get enough poles to do the job. ---
**Author:** ![Patch](https://avatars.discourse-cdn.com/v4/letter/p/a183cd/32.png) [@Patch](https://boards.straightdope.com/u/Patch)\ **Post date:** [July 7, 2012, 5:08pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/16 "2012-07-07T17:08:15Z")
So how could a standard homeowner shield his generator to block that big solar EMP and keep temporary power up? ---
**Author:** ![chappachula](https://avatars.discourse-cdn.com/v4/letter/c/d2c977/32.png) [@chappachula](https://boards.straightdope.com/u/chappachula)\ **Post date:** [July 7, 2012, 7:27pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/17 "2012-07-07T19:27:01Z")
> [@Heracles](#): > > once people have their food and shelter back, they still won’t have a job. I as a programmer wouldn’t have anything to do . There’s a problem with your logic here: If you as a programmer have nothing to do, then people _won’t be able_ to get their food and shelter back. Food can’t be distributed to supermarkets without electronics. Sure, it worked fine in 1940, and 1950 and even later. But nowadays,it’s all electroinic-- the finances behind the farming, the logistics of trucking, the check-out registers at the store and the salaries of the consumers who pay for it . Which means you need the programmers to get back to work _before_ the food and shelter can be restored. But you can’t put the programmers to work if there’s no food and shelter. Lather, Rinse, Repeat. ---
**Author:** ![Michael63129](https://avatars.discourse-cdn.com/v4/letter/m/3da27b/32.png) [@Michael63129](https://boards.straightdope.com/u/Michael63129)\ **Post date:** [July 7, 2012, 8:40pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/18 "2012-07-07T20:40:52Z")
> [@Heracles](#): > > What is not clear to me is what parts of electronics will fail. Is the individual transistor fried? Or does it just malfunction for a few seconds, which means the surrouding circuits are overloaded or submitted to currents, voltages, stresses they’re not designed to handle, which quickly fries out capacitors and such? It’s usually the opposite; transistors are usually damaged by external overloads or failed components, either due to overvoltage or overcurrent (as would come from an EMP, but the current has to find its way into the circuit first). I also suspect that modern electronics may be less susceptible to EMP effects because they are much smaller (remember, loop area determines how much voltage and current can be induced), and many IC chips and transistors are rated to withstand ESD (not the same, but it also involves high current/voltage spikes, typically several thousand volts or more through a limiting impedance) or avalanche breakdown. ---
**Author:** ![ftg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ftg/32/2801_2.png) [@ftg](https://boards.straightdope.com/u/ftg)\ **Post date:** [July 7, 2012, 9:39pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/19 "2012-07-07T21:39:03Z")
> [@Patch](#): > > So how could a standard homeowner shield his generator to block that big solar EMP and keep temporary power up? Have everything off line when it hits. Generator off, as much unplugged as possible. Nothing connected to the grid at all. If you are connected to the grid when it hits, a lot of your stuff is fried. The generator (not running) won’t help. A basic whole house surge protector might mitigate a few things, but it isn’t going to be rated for a full nuke EMP. If your generator and what you want to power survives the hit, the big issue is going to be what is the generator going to use for fuel after your supply is used up? The local gas stations aren’t going to open for a good long time. Note that wires and such act as the antennas for absorbing the EMP pulse and sending it down the line into transformers, your house, etc. So the longer the better and a utility grid makes a great antenna. For the disabling the local jerk situation, you don’t have miles of wire and a huge pulse but you are a whole lot closer. The wiring in the car will pick it up and send it to all the nice little computer parts in a modern car and fry them. While it all looks very doom and gloom for the nuke pulse scenario, there is a silver lining behind that mushroom cloud. Well, it probably won’t be as bad all over. First of all, not all nukes are created equally. H-bombs do a really great job, ones like the North Koreans blasted are not anywhere in the same league by orders of magnitude. Furthermore, you need an air burst. Preferably very high up in the atmosphere for an H-bomb. For a fission bomb, you go too high and it eventually becomes less effective. A ground burst will only fry part of a large city. Very few countries have the capability to burst H-bombs at high altitude over the US. Really just China and Russia in terms of enemies. At that point, it’s WWIII and EMP is the least of every human’s problems. N. Korea or Iran setting off a smuggled in bomb in a city is “just” going to take out that city’s electronics for a few miles around. Hardly anything to worry about. Except for the blast, radiation, zombies, etc. ---
**Author:** ![Flyer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/flyer/32/7298_2.png) [@Flyer](https://boards.straightdope.com/u/Flyer)\ **Post date:** [July 7, 2012, 11:56pm UTC](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412/20 "2012-07-07T23:56:44Z")
This may be somewhat sensationalized, but it’s distinctly scary, nonetheless. > [@](#): > > The Earth has a roughly 12 percent chance of experiencing an enormous megaflare erupting from the sun in the next decade. This event could potentially cause trillions of dollars’ worth of damage and take up to a decade to recover from. [http://www.wired.com/wiredscience/2012/02/massive-solar-flare](http://www.wired.com/wiredscience/2012/02/massive-solar-flare) If that estimate is anywhere near accurate, then a re-do of the Carrington Event is probably more likely than somebody attacking us with an EMP. The silver lining is that today, we can see it coming. A last-ditch defense would be for the grid operators to shut things down before the worst of the CME reached us. > [@](#): > > Even now, the center’s Bogdan said, the most damaging emissions from big storms travel slowly enough to be detected by sun-watching satellites well before the particles strike Earth. “That gives us [about] 20 hours to determine what actions we need to take,” Viereck said. > > In a pinch, power companies could protect valuable transformers by taking them offline before the storm strikes. That would produce local blackouts, but they wouldn’t last for long. > **[National Geographic](https://www.nationalgeographic.com/)** > > Explore National Geographic. A world leader in geography, cartography and exploration. [Next page](https://boards.straightdope.com/t/emp-power-systems-and-fuses/627412.md?page=2)