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Superconductors as Electrical Grid Surge Suppressors

securitas writes "The New York Times published a story about Intermagnetics -- a company that plans to use 'superconductors as valves on the electric-utility power grid, letting their temperature rise to choke off the flow of power,' a day before the largest blackout in North American history. The timing couldn't have been better. On the day of the blackout, Intermagnetics announced a $6 million contract from the Department of Energy to develop and install superconductor 'valve' prototypes by 2006 in the Niagara Mohawk distribution system. Considering that one of the leading theories for the cause of the cascading blackout is a surge in the Niagara Mohawk power grid, this announcement seems incredibly timely."

44 of 162 comments (clear)

  1. Linux by Amsterdam+Vallon · · Score: 2, Insightful

    That's one thing I like about my Linux hardware -- almost all of it uses less power than its proprietary counterpart.

    Actually conserving power instead of upgrading the power grids is an underrated option. We need to customize our appliances better, and in some cases, Linux might very well be the answer.

    --

    Reply or e-mail; don't vaguely moderate. Ex-O'Reilly/MIT employee, now a full-time Google employee.
    1. Re:Linux by mopslik · · Score: 2, Funny

      I fail to see how hardware running linux is going to use markedly more or less power than hardware running any other operating system.

      Actually, Windows requires less energy to run, since users spend half their time powering down and rebooting.

  2. NYTimes name change by duvel · · Score: 4, Funny
    > The New York Times published a story ........... a day before the largest blackout in North American history

    In related news, NYTimes is considering a namechange to NYFutureTimes

    --

    I have a photographic memory for numbers. I know almost a hundred of them.

  3. Hmm. by xenoweeno · · Score: 4, Funny

    this announcement seems incredibly timely.

    A little too timely.

    /me twirls handlebar moustache

  4. Problems by JamesP · · Score: 2, Interesting

    I don't know how is this supossed to work.

    Ok, so you can have a very tiny wire, that when superconductiong can carry several amperes... But if it heats and looses its superconductivity, it would just break like a fuse...

    I mean, why not use a regular fuse??

    --
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    1. Re:Problems by Al-Hala · · Score: 4, Informative

      Given the amount of power flowing through these lines, you cannot use a normal or even semi-normal fuse.

      A fuse works by breaking the conductor path, stopping the current flow. At high currents and voltages, the breakpoint will heat up, ionize, and provide a LOW impedence path, which is difficult to break.

      Some devices that are used to interrupt mains current are switches with contacts immersed in heavy oils, those that use an air blast to disperse the ionized air path, and other more exotic systems.

    2. Re:Problems by mikewolf · · Score: 2, Insightful

      well, if you would just RTFA.

      from the article "the surge is so large that it will arc across the circuit breaker's contacts, defeating its purpose."

      From what i can tell, you can only allow so much power to go through circuit breakers, otherwise it could arc across the breaker. With these new superconducting switches, you can push more energy through the grid.

      "Allowing larger electricity flows through substations without fear of overpowering the circuit breakers would let power companies move more energy through the grid."

      its amazing how much reading an article makes talking about it easier...

    3. Re:Problems by menscher · · Score: 2, Interesting
      Actually, the problem is that when the device *does* break, it heats up a LOT. That means that the liquid nitrogen is no longer a liquid. It vaporizes so quickly that you have to have a pressure-release valve to avoid an explosion. Assuming your device doesn't melt, cooling it back down again is a lenghly process.

      They have these sorts of issues at particle accelerators, like at Fermilab.

    4. Re:Problems by theMightyE · · Score: 3, Insightful
      Actually, the problem is that when the device *does* break, it heats up a LOT. That means that the liquid nitrogen is no longer a liquid. It vaporizes so quickly that you have to have a pressure-release valve to avoid an explosion. Assuming your device doesn't melt, cooling it back down again is a lenghly process.

      Very true - as a student I used to work at a superconductor research lab that did this kind of work. We would run 100kA through a superconducting coil cooled with liquid nitrogen as part of our experiments, creating a magnetic field with about 3 megaJoules of stored energy. One day a tech mis-wired part of a safety circuit that was used to dump the energy at the end of the experiment run (and then very nicely faked his check-off sheet afterward), and the superconductor heated up so fast it vaporized the one inch aluminum stabalizing rod it was attached to as well as several hundred gallons of liquid He. A nine inch port blew out of the top venting all the (now gasseous) helium into the lab and we all ran like hell to avoid being smothered by the sudden lack of O2 in the room.

      Nobody got injured (except the tech, who got fired), but I couldn't help but think about the alternate scenario where the lab staff somehow got trapped inside the room, and the last thing I'd hear before passing out would be "We're all gonna die!" in a Mickey Mouse helium voice.

    5. Re:Problems by Euler · · Score: 2, Informative

      Besides the issue with interrupting high currents, this superconductor would help to keep power plants from tripping offline in the first place. When working with very high power, it is difficult to build regulators that can handle enough power. Switches/breakers are much easier to build, but they are only on-off. The superconductor apparently allows for some current regulation by varying the external magnetic fields.

      Power plants trip offline because they have only 2 choices: stay online and fry, or go offline and screw all the other plants into taking more burden. This superconductor gives a much better 3rd option: stay online, but only supply the rated capacity of the power plant.

  5. Fancy gadgets will help? by AndroidCat · · Score: 4, Funny
    They were supposed to have protection systems to prevent a cascade failure like this. Making the protection systems fancier isn't going to help too much if they don't install/maintain them properly.

    Or as Kosh said, "Once the blackout begins, it is too late to order pizza."

    --
    One line blog. I hear that they're called Twitters now.
    1. Re:Fancy gadgets will help? by QuantumFTL · · Score: 3, Interesting

      Making the protection systems fancier isn't going to help too much if they don't install/maintain them properly.

      This is not a simple matter of making the protection systems fancier... this is a fundamentally different approach to preventing cascade failure. It's orders of magnitude more robust (no arcing current, etc, as mentioned in the article) and there is no good reason why we shouldnt' have more robust systems.

      These sort of things won't all be maintained properly, however it is my hope that after this blackout the maintainence system is revised to minimize negligence. Having these systems installed will help the well-maintained stations not suffer due to the problems of the ill-maintained... It makes the whole system much fairer and could possibly save a lot of money in the long run.

      I also think that advancing superconducting technology is worth this effort alone, as it is a very promising field. A superconducting electric motor for an electric car would only have to be the size of a softball (extremely high magnetic field densities, and of course efficencies). Superconductors are being used in better bandpass filters for things like cellular telephone transceiver towers and possibly even space missions. Superconductors are also used for experiments with NMR quantum computing, and may hold the key to confined fusion (yes, a long way off I know).

      You are correct that there is an issue to be addressed with maintainence, however I cannot see how this could do anything but help the situation.

      Cheers,
      Justin

      P.S. Nice Kosh quote!

    2. Re:Fancy gadgets will help? by mkweise · · Score: 4, Informative

      They were supposed to have protection systems to prevent a cascade failure like this. Making the protection systems fancier isn't going to help too much if they don't install/maintain them properly.

      Actually, the primary purpose of the protection systems in place is to prevent grid trouble from physically destroying generators, transformers, transmission lines and other infrastructure hardware. And they worked, otherwise it would have taken weeks rather than hours to get the grid up again. IIRC, in the blackout of 1965>, major infrastructure damage resulted from a grid collapse and it was from this experince that many of the currently implemeted ideas were learned.

      --
      Gentlemen! You can't fight in here, this is the War Room!
  6. Timely?.. by levik · · Score: 2, Informative
    Actually, it seems very untimely to me... Like the announcement about installing bulletproof doors in jet liners two days after 9/11.

    Where were they three days ago, I wonder?

    --
    Ñ'
    1. Re:Timely?.. by Threni · · Score: 2, Insightful

      "Yeah, bulletproof doors would've really helped against those box cutters"

      Uh...yeah. They'd have meant that there'd have been no way they could get into the cockpit, so the worst that could happen would be everyone on the plane except the crew dying, which would have reduced the death toll by 99%.

  7. Re:Would seem to have the potential to make it wor by siliconwafer · · Score: 5, Informative

    How is this a storage device? It's supposed to increase its resistance when a large, sudden change in current takes place. In other words, it sounds like it would dampen an oscillation. I don't see how it could "inject" current into the grid.

  8. Unfortunatley. by anonymous+coword · · Score: 2, Informative

    This is very difficult to do. Anyone who knows anything beyond EE 101 knows that trying to stop electicity over 30,000 volts is heading for trouble. Unless you have a huge insultor that is at least 500,000 Ohms, the electricty will just jump over it without even slowing down.

    1. Re:Unfortunatley. by QuantumFTL · · Score: 4, Interesting

      Anyone who knows anything beyond EE 101 knows that trying to stop electicity over 30,000 volts is heading for trouble. Unless you have a huge insultor that is at least 500,000 Ohms, the electricty will just jump over it without even slowing down.

      And anyone who knows any physics knows that that statement is bullshit without some sort of geometrical context.

      Look at all the 350k powerlines out there... You don't see them arcing every day, because it's not voltage the makes the problem, it's electric field strength! These pipes are probably rather long, so the E-field strength that they will be experiencing should be quite small (E-field = potential / distance). The superconductors lose superconductivity during a surge, becoming a resister whose resistance is proportional to temperature. Due to I*R^2 ohmic heating, the resistance will shoot up rather quickly, thus cutting off the surge. Much of the surge's power will be turned into waste heat (I'd hate to have to design that cooling system) but it's much better than the alternative.

      It should also be clarified that arcing occurs precisely because circuit breakers, being mechanical, are not large enough to keep the E-field to a level that won't ionize the surrounding atmosphere (allowing arcing).

      Disclaimer: I'm a year away from my bachelors in Applied Physics.

    2. Re:Unfortunatley. by tlk+nnr · · Score: 2, Interesting

      These devices work because superconductors will no longer superconduct when the current density exceeds a certain threshold- when this happens, the superconductor becomes a regular conductor and is subject to I^2R heating.

      Not really correct.
      The article mentions that it will be a copper oxide based superconductor - a ceramic. When thresholds are reached, then the superconductor becomes an isolator. No danger of arcing, because there is no air that could be ionized.
      The threshold that they want to use is not the current or heat theshold, they want to use the magnetic threshold: Strong electromagnets are placed around the superconductor, and if the magnets are being turned on, then the conductivity falls to 0.
  9. stock change by jetlag11235 · · Score: 3, Interesting

    Wow, I suppose this isn't too surprising, but it isn't every day you see an established company have their stock increase by 17% in one day.

    -- jetlag --

  10. Yahoo news by DRWHOISME · · Score: 5, Informative

    says the cause of the blackouts were 3 OHIO transmission lines.

  11. Lastest new reports: transmission lines in Ohio... by pg133 · · Score: 2, Informative
  12. Larger electricity flows? by Avian+visitor · · Score: 2, Informative
    Allowing larger electricity flows through substations without fear of overpowering the circuit breakers would let power companies move more energy through the grid

    Ccircuit brakers are not limiting the amount of electrical power that can flow through a high-voltage line

    The diameter of cables limits the current and the distance between cables limits the voltage. Lines are designed for a specific capacity. You can't upgrade them only by chaging the breaker.

    Besides, they say that a normal circuit breaker would arc across. What would prevent an arc between the ends of their ceramic rods?

    If they want to use semiconductors, why don't they use them for the entire line? Or for the coils in the generators? That would make a difference, not some circuit brakers...

    1. Re:Larger electricity flows? by AndroidCat · · Score: 2, Insightful
      What would prevent an arc between the ends of their ceramic rods?

      At a guess, since they "valve" the current rather than just chopping it, they can dampen out the inductive kick that a circuit breaker gets.

      As for using superconductors for the whole line or generator coils, I think they need to keep their switch at 77 K.

      --
      One line blog. I hear that they're called Twitters now.
    2. Re:Larger electricity flows? by Al-Hala · · Score: 2, Informative

      Righto!

      Besides, they say that a normal circuit breaker would arc across.

      Absolutely true. Here's a link to an industrial line switch. Keep in mind this is a manually operated and "vanilla" type:
      Vac-Rupter

      What would prevent an arc between the ends of their ceramic rods?

      They'd need to break the arc using compressed air blown across the gap, or by submerging the contacts so the arc couldn't form in the first place.

      If they want to use semiconductors, why don't they use them for the entire line? Or for the coils in the generators? That would make a difference, not some circuit brakers...

      At this level of performance, no semiconductor could handle the power losses. Remember they are SEMI-conductors (not so good as conductors, not so bad as insulators). We use an AC distribution system due to physics: Using transformers, we can up the voltage, while reducing current, to get the same power level.

      The less actual current flowing through a conductor, the less heating of said conductor. The less heating, the thinner/less expensive it can be. Imagine supporting a cable across countries the diameter of a bus.

  13. Re:US electricity consumtion is legendary! by Firefly1 · · Score: 2, Insightful
    Or maybe you can SCRAP YOUR SUV's and walk.
    Objection - relevance; as in 'lack thereof'. Do many cities in the United States need a better public transit plan? Yes. Does this have anything to do with the hardware failure suspected to be at the bottom of the recent unpleasantness? No.
    Pull the other one, it's got bells on.
    --
    - White Knight of the Order of Mihoshi Enthusiasts
  14. This is a good start by Judg3 · · Score: 5, Interesting

    This is a great start, especially with the way the power grid is now.
    Essentially right now a surge large enough to damage substations creates a large chain effect, where the incoming substation sees the surge, shuts itself down to protect itself, which adds more power to the surge, which heads down to the next station, which shuts off to keep itself from being blown, which adds more power to the surge, etc etc.

    With a way to contain a large surge into the system, we could prevent blackouts like the one that occured in NYC in 1977 (Exactly because of this reason). In 1977 a summer storm knocked several high-voltage power lines out of order. Because of the suddenly reduced load, the power tried to flow back to the substation, which knew it couldn't handle it and shut down. This added more power to the grid, which was sent to the next station along the line, which shut itself off, etc. This cycle of power overload, substation shut down happened for about 55 mins till it hit the main generators (which, although they could shut themselves down, had no way to offload this excess power down the line) and took them out for 25 hours.

    I said it before, I'll say it again. Get rid of our 30+ year old nuclear reactors (no new orders for units since 1977) and replace them with newer more powerful solutions and second generation solar equipment.
    When reactors are running at 102.41% capacity, it's time for an upgrade.
    We've got the technology now to produce cleaner, safer, more powerful nuclear reactors - but that Three Mile Island paranoia still looms with us I guess.
    Look at European nations, they derive up to 50% of their power from modern nuclear facilites without any problem and no blackouts. The USA? Just 20% of our power comes from Nuclear energy, the rest from coal fired power plants and "peak use" and "daytime use" gas turbine generators.

    Hey, I don't want to live right next door to a huge nuke power plant myself, but if it means cleaner, safer, more reliable power I'd be more then happy to.

    --
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    1. Re:This is a good start by Anonymous Coward · · Score: 3, Informative

      Dude, that 102.4% only means that the plant operated more efficiently than normal. The amount of power generated by the core did NOT exceed 100%. However, the generator output exceed the maximum dependaple capability (MDC) as a result of higher conversion efficiency. The MDC is a lower bound on what the plant -as a whole- can reliably deliver to the grid. All it takes to achieve better efficiency is lower than "normal" temperature of circ water to the condenser. This can simply be caused by weather conditions. I've seen nuclear plants whose output could vary by more than 100 MWe over the course of a year, solely due to seasonal changes in ambient temperatures. Lower temperature of heat sink = higher thermal efficiency = higher capacity factor.

    2. Re:This is a good start by Ralph+Wiggam · · Score: 2, Interesting

      I agree that the fact that no nuclear power plant has been built here in 25 years is a disgrace.

      The only reason I wouldn't want to live next to a nuclear plant is because they keep all the spent uranium in a swimming pool right there. If there were a national waste depository it would be a huge step towards making the whole system work. I can't believe that the DOD and Homeland Security havn't put their foot down and said that we can't have tons of potential dirty bomb material spread all over the country protected by a chain link fence and a rent a cop. No more feasablility studies (which I think at last count have cost a few BILLION dollars), we're just going to build the thing and Greenpeace can sue us for the next 17 years.

      -B

    3. Re:This is a good start by dpletche · · Score: 2, Informative

      Likewise, all that waste is sitting around in pools (though warm as they are, I wouldn't want to swim in them) because Carter signed an executive order banning reprocessing (known as Presidential Directive 8, subsequently reaffirmed as President Clinton's Presidential Directive 13.) There are certainly issues to consider with reprocessing, but it's a fact that we wouldn't have all this nuclear waste lying around if we recycled it into useful component elements.

      Interesting discussion:
      PBS Frontline
      University of Minnesota Technology newsletter

  15. Don't come to the UK for electric by DrSkwid · · Score: 3, Interesting

    Energy traders, power producers and chemical engineers warned yesterday that the UK could face blackouts on the scale experienced in the US and Canada on Thursday night or substantial disconnections at the very least.

    echo ' http://www.guardian.co.uk/uk_news/story/0,3604,101 9996,00.html ' | tr -d ' '

    --
    There are places where the networks are not touching,and there are places where they are-Boeing's Lori Gunter
  16. Re:Is it just me, or is it a conspiracy .... by Attaturk · · Score: 2, Insightful

    Is it just me, for in this "New" world, everytime I see a coincidence, me thinks conspiracy ....

    To write off one coincidence as a conspiracy theory may be regarded as misguided; to write off more than one coincidence as a conspiracy theory is naivite.

    You are not alone. The fact that we can't trust those in charge any more may have something to do with the lack of accountability and openness.

    The lack of openness could be put down to justified fear, given global opinion of the United States at the moment. There is however no excuse for the lack of accountability. What happens to senior executives and politicians that mess up our lives? They retire with a fat pay-off. Therein lies the problem.

  17. The fix is to force MaxLoad less than Supply by douglasgodfrey · · Score: 3, Interesting

    The fix is to force MaxLoad less than Supply.

    This can be done by replacing the local
    stepdown transformers that convert from
    17KVA Power Lines to the 220/110V 3 Phase
    local Power Lines with saturation mode
    transformers that will not allow more
    than their maximum rated power to pass.

    Power Stations can be protected by
    Superconducting Air Gap Transformers
    that inherently limit the transfer of
    power to the rated capacity of the
    station. Power Stations would then be
    able to stay online through a major
    overload without damage.

    Any major overload or failure of the
    Transmission Grid would cause a brownout
    but would not cause a blackout.

    Any localized overload would cause a
    local browout without causing any
    voltage or current instabilities on the
    high voltage Power Lines.

  18. Just a tutorial by t_allardyce · · Score: 5, Informative

    for all of us who failed electronics/electrical engineering: blackouts for dummys

    --
    This comment does not represent the views or opinions of the user.
  19. Intermagnetics hype by Animats · · Score: 3, Insightful
    This is hype. That technology isn't ready for prime time. Read the paper. The "high temperature superconductor" they're using needs temperatures below that of liquid nitrogen.

    Utilities have been testing various superconductive devices for decades, but nobody has deployed them in volume. Superconducting generators have been built by GE and others, but they only offer an 0.5% efficiency improvement over conventional machines. That's not enough to compensate for the added complexity of running a big machine at cyrogenic temperatures.

    If this technology worked at liquid nitrogen temperatures, it might have a chance. But anything that needs to go colder than that is probably going to be more expensive and less reliable than what's used now. Scroll down to the end of the article and see the comments from utility companies.

    Look who's doing this: General Atomics and LANL, the senior activity centers for over-the-hill bomb designers.

    If room-temperature superconductors are ever developed, all this will change, but right now, this is basically big-budget overclocking.

    1. Re:Intermagnetics hype by deglr6328 · · Score: 3, Informative

      uhh hello? I dont know why this is modded to +4 since it's just plain wrong. If you'd actually read the article you linked to and the NYT article you would've known that they're now using BSCCO high temperature superconductors which have critical temperatures well above the boiling point of liquid N2(over 100K).

      --
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  20. Hmm... Black Out... by Greyfox · · Score: 3, Informative

    Greg Pallast has some Interesting Comments on the blackout. He cites energy deregulation, passed by George Bush, Sr. under lobbying pressure from Enron (Yes, them again!) Very intersting comments, if true. Politicians and Corporations teaming up to line their own pockets while endangering the public. Nice.

    --

    I'm trying to teach myself to set people on fire with my mind... Is it hot in here?

    1. Re:Hmm... Black Out... by Allen+Varney · · Score: 2, Interesting

      Palast's piece was invigorating and/or infuriating, regardless of the reader's own politics. I give him a hearty cheer for intent and a solid +5 Flamebait for phrasing his argument in such a way as to polarize everyone reading it. I wanted to say both "Bravo!" and "Can't we all just get along?"

      Bruce Sterling reprinted Palast's ZNet piece in his latest Vridian Note. A typically inflammatory extract:

      "Meanwhile, the deregulation bug made it to New York where Republican Governor George Pataki and his industry-picked utility commissioners ripped the lid off electric bills and relieved my old friends at Niagara Mohawk of the expensive obligation to properly fund the maintenance of the grid system.

      "And the Pataki-Bush Axis of Weasels permitted something that must have former New York governor Roosevelt spinning in his wheelchair in Heaven: They allowed a foreign company, the notoriously incompetent National Grid of England, to buy up NiMo, get rid of 800 workers and pocket most of their wages -- producing a bonus for NiMo stockholders approaching $90 million.

      "Is tonight's black-out a surprise? Heck, no, not to us in the field who've watched Bush's buddies flick the switches across the globe. In Brazil, Houston Industries seized ownership of Rio de Janeiro's electric company. The Texans (aided by their French partners) fired workers, raised prices, cut maintenance expenditures and, CLICK! the juice went out so often the locals now call it, 'Rio Dark.'

      "So too the free-market British buckaroos controlling Niagara Mohawk raised prices, slashed staff, cut maintenance and CLICK! -- New York joins Brazil in the Dark Ages.

      "Californians have found the solution to the deregulation disaster: recall the only governor in the nation with the cojones to stand up to the electricity price fixers. And unlike Arnold Schwarzenegger, Gov. Gray Davis stood alone against the bad guys without using a body double. Davis called Reliant Corp of Houston a pack of 'pirates' -- and now he'll walk the plank for daring to stand up to the Texas marauders.

      "So where's the President? Just before he landed on the deck of the Abe Lincoln, the White House was so concerned about our brave troops facing the foe that they used the cover of war for a new push in Congress for yet more electricity deregulation. This has a certain logic: there's no sense defeating Iraq if a hostile regime remains in California.

      "Sitting in the dark, as my laptop battery runs low, I don't know if the truth about deregulation will ever see the light -- until we change the dim bulb in the White House."

  21. World Wide Electric Grid by 2030 by cyberguyd · · Score: 3, Informative

    Source: Wired Mag September 2003 - paper copy

    Talk about timely articles. The day of the blackout the September issue of Wired was in my mailbox. In this months infop0rn, it describes a plan that Buckminster Fuller dreamed up 30 years ago to connect the world on the same grid. "Electric companies dismissed the notion as pie in the sky - and then proceeded to build such a grid." The article states that all the contries in the Western Hemisphere will be interconnected within the next ten years. About half the countries in the world are interconnected in some way already. Those that aren't connected or can't be is because of a geographical, industrial infrastructure, or politcal nature, ie Cuba, a few contries in Africa like Ethiopia and Sudan and Polynesia, Austrailia, and New Zealand.

    The article says that this should smooth out market spikes when demand is high in one region it is almost certainly to be low in another. The US uses about 3.8E+18 kilowatt hours a year with about 71% of the energy used produced from fossil fuels. The US is also the largets importer of electricity, most likely the majority from Canada which produces about 58% from hydropower. France is the leading producer of electricity from nuclear, about 75%, and Brazil from hydro, about 86%.

  22. "Quenching" a superconductor by Anonymous Coward · · Score: 4, Informative

    Once upon a time, it was discovered that if you cool certain materials below a critical temperature, they lose all resistivity, i.e. superconducting magnets are only superconducting below a certain temperature. Once their temperature exceeds that critical temperature, "quenching" occurs. The resistance suddenly becomes "normal," i.e. dramtically increasing. This can be catastrophic, the temperature and resistance suddenly becoming directly related and both increasing at accelerated rates. All that energy in the magnetic field suddenly becomes heat.

    When I was an undergraduate at Rice University, I got to use the NMR machine in the chemistry department. Essentially, it's a large superconducting magnet that is used to investigate the structure of chemical samples with radio waves.

    The superconductor is contained in a large steel thermos. The inner layers are cooled by liquid helium (4 K), outer layers by liquid nitorgen (78 K). Superconductors are used because a large amount of current can be used, producing a larger magnetic flux, etc. The more powerful the magnet, the easier the determination of structure.

    Every few days the liquid helium and liquid nitrogen would have to be added to maintain the temperature control.

    I was warned that if the magnetic every quenched, it would sound like a freight train. Remaining liquid nitogen or helium would boil and the magnet itself would probably melt. One moment it's a multi-million dollar instrument, the next it's a steam whistle with a heart of worthless slag.

    I was told that if this happened on my watch, I should run to my car, drive to Mexico, and hope the my professor's hitmen never found me.

    Magnets are transported to the location of installation before being cooled and and superconducting is initiated. Once installed, they are precarious to relocate. Major concerns:

    1) slight bumps can disrupt internal structures causing annoying variations in the magnetic field- don't be the chemist who brings a wrench in the room and gets it permanently attached to the side of the container
    2) loss of temperature control - the quenching phenomenon.
    3) a very high-powered magnetic field- you can exactly push down the hallway without causing damage to nearby objects or its own the magetic field

    If this quenching was used to control current, it would have to be carefully controlled to avoid catastrophic damage to the superconductor itself. This seems a nontrivial engineering problem.

  23. Re:Lastest new reports: transmission lines in Ohio by afidel · · Score: 2, Insightful

    Doesn't suprise me at ALL. First Energy is the same company that operates the David Bessy nuclear plant that fell into such disrepair that the Federal Energy Commision ordered them not to restart it. The reason was an 8" hole in the reactor containment unit which had been eaten by corrosive acid! Even after the containment cap was replaced the commission was reluctant to allow the plant to restart as there were other worries about the plants safety and self-inspection records. Basically these guys suck and are the definition of what bad things happen when a formerly regulated monopoly is handed free infrastructure and told to make as much money as possible off it with minimal investment in a newly deregulated environment.

    --
    There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
  24. Re:Coincidence? by uncoveror · · Score: 2, Funny

    It wasn't Microsoft. It was the Zhti Ti Kofft. Put on your tinfoil hat!

    --
    The Uncoveror: It's the real news.
  25. Nothing to do with the recent blackout by grumio · · Score: 3, Interesting

    These devices don't have much to do with the recent US blackouts. They are intended to help manage high short circuit currents in electricity transmission and distribution networks.

    As electricity transmission networks grow larger and more interconnected, the current that flows following a short circuit also grows. The maximum level of this short circuit current is a critical parameter when selecting circuit breakers, as all circuit breakers you have must be rated to interrupt the highest possible level of short circuit current that can occur. As transmission networks get larger, eventually you begin reaching circuit breaker short circuit ratings, and the fun begins. You can either start wholesale replacement of your circuit breakers at around $100-200k each, depending on the voltage, or you start splitting up your transmission network to reduce maximum short circuit currents.

    What the devices in this article are intended to do reduce short circuit currents, without affecting normal load current. Under normal load conditions they will behave as a super conductor, but under fault current conditions they will rapidly revert to a high resistance, and hence reduce to fault currents to within circuit breaker ratings.

    Unfortunately the 'liquid nitrogen' aspect of them makes them impractical for real world, large-scale use. Power transmission equipment routinely has uptimes measured in years (recent blackouts excepted of course), and until room temperature, uncooled superconductors come along, I believe this technology is unlikely to be more than an academic curiosity.

  26. Re:Superconductors can have serious drawbacks by anubi · · Score: 2, Interesting
    The only thing that concerns me is these things are terribly nonlinear. Once you get a hot-spot resulting from the transition from zero to normal resistance, you will get tremendous dissipation in that one spot. These rods don't appear to be all that big.. I wonder which would have more energy in it, the stored rotational energy of a large hydroelelectric dynamo, or a good-sized stick of TNT?

    They are cooling them with liquid nitrogen... if you dump a helluva lot of energy into it, you get a phase change into gas. Gas doesn't conduct heat very well, so formation of gas bubbles on the rods could have really unusual nonlinear thermal effects.

    They are using magnetic triggers.. with the amount of current which will be supposedly flowing in these conductors, there will be a lot of stray magnetic gradients in the vicinity. Its gonna be a good work of art to ensure your magnetic trigger pulse will be uniform across the "melt-cast" conductors so they drop out of superconductivity gracefully.

    They switch in a fraction of a second.. will a thunderstorm strike set it off?

    Right now, I am quite ignorant of the technology, so don't take anything I say seriously.. its just I am aware there is a helluva lot of energy that they are dealing with. This does not look like an easy engineering problem. If they can pull this off, they've definitely earned their pay.

    --
    "Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]