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Scientists Create New Type of Superconductor Wires 96

An anonymous reader writes "Scientists in Israel have used technology created at a U.S.-funded national research lab to created a new kind of wire spun from sapphire crystals, that is a vastly better conductor than traditional copper wires. The research could have profound implications for renewable energy since much of the generation is in remote locations. It could help bring more electricity from renewable sources to cities."
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Scientists Create New Type of Superconductor Wires

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  • by ColdWetDog ( 752185 ) on Wednesday September 07, 2011 @07:49PM (#37334508) Homepage

    So, this stuff won't cure cancer, but it might help with renewable energy:

    Among the many other possible beneficiaries of the team's new creation that comes to mind would be the hyper-ambitious international DESERTEC organization, which seeks to harvest massive amounts of solar energy in deserts and transmit it to population centers, for example from Africa to Europe.

    Except for the small detail that it has to be cooled to liquid nitrogen temperature to act as superconductor and an entire desert transmission line sitting in LN would take a bunch of energy, what's not to like?

    • It's less than ideal, but the fact that it's only liquid nitrogen and not some of the more expensive coolants that they used to use is a significant step.

      • Certainly better than liquid helium but I don't think that long distance LN cooled transmission lines are going to be a very useful concept.

        I'm not saying that this tech isn't going to be useful - it very well might be. I'm just annoyed because stuffing it into a 'renewable energy' story seems silly. Just like every bit of biological research 'might help cure cancer'.

        • by EdZ ( 755139 )
          Depends on what is greater: the energy used to refrigerate the superconducting wires, or the transmission losses of regular wires over the same distance. By heavily insulating and burying the wires you could probably keep the cooling requirements down, and as the wires get longer the transmission losses increase. A trans-continental run would probably be long enough that transmission losses from conventional cables make it unfeasible.
          • Re: (Score:2, Insightful)

            by Anonymous Coward

            > as the wires get longer the transmission losses increase

            It's superconducting wire; the point is that there's no transmission loss.

            However, as the length increases, the coolant loss will increase. But even that isn't as bad as it sounds. After all, since the wire is superconducting, the wire itself isn't adding heat to the coolant - it's only the outside that is heating the coolant. So heavily insulated underground wiring would actually work pretty well. And if liquid nitrogen conducts heat well enough,

            • I've heard that superconductors not only have no electrical resistance, but the have no thermal resistance too. That would mean superconductors have a constant temperature across them; is this true?

              • Superconductors have a finite thermal conductivity, so there are temperature gradients. The substrate material (in this case sapphire) is actually responsible for most of the local heat dissipation in high temperature superconducting wires.
              • I've heard that superconductors ... have no thermal resistance ...

                You're thinking of Scrith from Ringworld Engineers []. It's a thermal superconductor.

            • It's superconducting wire; the point is that there's no transmission loss.

              He obviously was speaking about the losses of normal wires.

              In short:
              * Transporting a certain amount of power over a normal wire gives a certain loss due to electrical resistance.
              * A superconducting wire gives a certain loss due to cooling (while the current flow itself has no losses, you have to additionally provide the power for cooling, so the effect is the same: You have to put more power in than you get out).

              The question is: Which

        • Yes, even at $14 or so a liter, the stuff isn't cheap, but it is a step in the right direction. I'm just surprised that they're suggesting that something like this that relies upon liquid cooling is acceptable for transmission lines. As it is they literally have to go around with guys in specially design suits, lowering them onto the transmission lines to alleviate hots spots. I can only imagine what would happen if a section of the transmission line were to start leaking coolant.

          • by aXis100 ( 690904 )

            Nah, it's much cheaper than that - in bulk and generated on-site it costs only cents per litre.

          • Like Axis said, it's a lot cheaper if made on site. Also, as I understand it the way superconducting power lines are made(there are a few already), they're made of liquid-proof, but not gas tight highly insulated cables.

            As the cable is superconducting, you don't have heat buildup from resistance, so it's all environmental. You simply have enough space around the tubes for the nitrogen to disburse. Nitrogen is non-toxic, though you might want an O2 mask in some circumstances.

            As the nitrogen is a liquid, t

          • The utilities in some places already hook up liquid nitrogen tanks to some underground lines, as the LN2 is a good way to drive moisture out of the lines. You might have seen them on the side of the road, often chained to a utility pole. A guy in a truck pulls up and changes the tank as necessary, no special gear required.

            I can think of worse chemicals to have spill of than Nitrogen.

        • by sribe ( 304414 )

          Certainly better than liquid helium but I don't think that long distance LN cooled transmission lines are going to be a very useful concept.

          The ratio of energy saved by reduced conduction to that required to cool the nitrogen is huge. And distance doesn't really change that--energy saved increases with distance, just as does the amount of cooling required. Superconducting power lines have already been in use for some years to carry power from plants in New Jersey into Manhattan. Of course the Nevada desert is warmer than the water between NJ & NY, but the thermal conductivity of water is greater, so in reality add a little more insulation a

    • by Nethead ( 1563 )

      But they'll have to heat it a bit for it to work in Fairbanks. ;)

    • In bulk liquid nitrogen costs less than milk.
      • In bulk liquid nitrogen costs less than milk.
        In that case we'll clearly need some price support for LN2.
        (Deep sarcasm, for those not familiar with the "distance from farm" pricing rules currently in effect for milk in the USA)

  • I'm guessing this does not exhibit the phenomenon known as "superconductivity" and is rather just a low-resistance conductor.
    • It's actually superconducting. From the article:

      The TAU research team took the project a step farther by combining the fibers with a self-contained cooling system based on liquid nitrogen, which keeps the sapphire wire in a highly efficient superconducting state without overheating.

  • Electrons on the outside, photons on the inside. Double the bandwidth.
  • Even if it needs liquid nitrogen cooling at least nitrogen is abundant unlike helium.

    If the cost for cooling per mile/kilometer is less than the profit generated by solar power from a desert region then I can see someone giving it a go. Unfortunately, there isn't any rough costs for doing so in the article.

    I wonder if they are using electric blue sapphires?

  • BETTER ARTICLE (Score:5, Informative)

    by Dthief ( 1700318 ) on Wednesday September 07, 2011 @08:04PM (#37334610)
  • This news is quite strange. As far as I know sapphire itself is NEVER a superconductor at any temperature. The superconductivity might just come from the "specialized ceramic coating" that is mentioned, since the LN2 temperature superconductors are usually ceramics, so called "high temperature superconductor". The problem of such material is that it is quite brittle and you can never draw a wire with it. I assume the improvement here is how to fabricate such wire with this material.
  • Is there any particular reason the USA is paying for a lab to be built in Israel while, at the same time, people are complaining about how we can't build or innovate anything in the USA?
    • Re: (Score:2, Funny)

      by ColdWetDog ( 752185 )

      Is there any particular reason the USA is paying for a lab to be built in Israel while, at the same time, people are complaining about how we can't build or innovate anything in the USA?

      If Israel were physically closer, it would either be the 51st state or a borough of New York City.

    • AIPAC. Next question?
  • by Stenboj ( 1131557 ) on Wednesday September 07, 2011 @08:42PM (#37334882)
    See [] which I reached via the sapphire outfit's site. The sapphire is a substrate for epitaxial deposition of an unspecified superconductor. It is not the conductor and the story is making more sense now.
  • As Bernd T. Matthius, the famous physicist, used to say when people touted this or that new superconducting material, "Make me a cable!" Exotic materials that work in the lab often can't be made into a cable of any length or usefulness.
  • It could help bring more electricity from renewable sources to cities

    It could also help bring more electricity from non-renewable sources to cities. And villages.

  • Or we could - you know - boost the voltage a transformer and transfer the power over small conductors with relatively low losses,

    And for longer runs we could use High Voltage DC []

    But liquid nitrogen and sapphire would work too...

  • If you're running superconducting lines, you can bury them because you don't need to worry about them getting grounded. That means fewer weather related power outages.

    • But a lot more graboid related ones. I hate those things.

    • If you're running superconducting lines, you can bury them because you don't need to worry about them getting grounded.

      Why wouldn't you? The current presumably goes through the resistive coil in your oven; why would it not go through the ground as well?

      • Because superconductors work at much lower voltages, so they are easier to insulate. Typically if you're running high voltage lines underground you'd need to put too much insulation on them to be practical (and that insulation would result in the need for a lot of active cooling). With superconductors, that isn't a problem.

  • by drolli ( 522659 ) on Thursday September 08, 2011 @04:16AM (#37337296) Journal

    Interesting approach, but the linked article is so bad even i had to scratch my head for a few minutes and follow the link to the company to understand it (Sapphire is a nearly perfect insulator, even at low temperatures, what the linked article calls glue seems to be the (epitaxially grown?) HTC SC material).

    to address some comments here: the use of liquid nitrogen is not the special thing here. Cables cooled by liquid nitrogen have been in test for a long time.

    What i am missing is a comparison to other superconducting cables, so AFAIU:

    Normally to make HTC SC wire you grow HTC crystals (a dark art by itself, much like cooking), crush these and press it into a metal band to be able to bend the conductor and you essentially hope that somehoe the grains inside the filaments touch each other (they do). The current is only carried in the surface of the grains anyway and these HTCs are brittle, so you can in principle use a very stable insulator core (like sapphire), grow a thin layer of HTC on it (of which you can control the composition perfectly) and save the effort of providing additional mechanical stability.

    • by thed8 ( 1739450 )
      First all this is written in advertising speak so it gives few facts and as many buzz words as possible. Second what the heqq does it have to do with renewable power? If you can spin saphire fibers that carry 40 times what copper can that's significant. Take a 0000 cable it weighs about 640 pounds per 1000 feet. Thats a big mass change. It doesn't really fit but a 0000 can carry about 223 amps you could scale that back to a like an #18 gauge wire (which weighs about 5 pounds per 1000 feet) and carry the sam
  • This is only going to make the problem of cable theft even worse! My train is frequently delayed because some selfish numbnut has stolen the signalling/power cables to sell the copper. Imagine what is going to happen when they find out that these cables are made out of sapphires!
    • Just wait until those same numbnuts find out about diamond tip industrial cutting tools, or diamond abrasives.
    • by HiThere ( 15173 )

      Assuming that you're serious (though doubting it):

      Copper is malleable, and melts at a reasonable temperature. So you can take a piece of copper wire and melt it or cold work it.

      Sapphire is brittle, and doesn't melt easily. (I forget whether you need a vacuum, an atmosphere of inert gasses, or whether nitrogen is required. But in any case it's not at a reasonable temperature.) So if you steal a piece of sapphire cable, what you have is a piece of sapphire cable. It's quite unlikely to be a pretty as a p

  • Imagine a wires made out of sapphire. I am not sure they will be financially viable for long distance usage. Copper is getting stolen, imagine safeguarding sapphire wires!!

  • by ansak ( 80421 ) on Thursday September 08, 2011 @08:53AM (#37338862) Homepage Journal
    Okay, so IEEE has the bulk of the article behind a pay wall but the abstract here [] makes it plain that we're talking about superconduction at 77 K, close to the boiling point of Nitrogen [] but as someone pointed out, Sapphire is the substrate on which another high-temperature superconductor is laid out and the resulting material only superconducts at microwave frequencies.

    But any advance in this area is a good thing, if you ask me. We don't have enough copper to serve everyone's needs and its Ohm's Law losses are too much to be acceptable in the future.


  • First, I thought sapphires were less abundant than copper making it much more expensive no matter the process.

    But advances in low cost production technologies has changed the equation, making the mass use of such fibers a potential possibility.

    Second, I had no idea there was a self-contained liquid nitrogen system that could be applied to the actual wire. Why hasn't this replaced liquid nitrogen stations? Please tell me this is a confusion on the part of the writer.

    The TAU research team took the project a

  • Here is a thought. If you lived in Australia, close to both the desert and the ocean, and have the technology listed below; would you become our new OPEC style rich overlords?

    1) You are capable of creating glass fiber from sand using solar energy (solar oven).
    2) You are able to use the glass as an insulator for superconductive wire.
    3) You are capable of using solar energy to create hydrogen from the ocean which then can then be used to super cool the wire.
    4) You are able to run the wire on the ocean floor

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