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I assume that when you said HTS wires transfer without resistance, did you mean with very little resistance as compared to copper?

I get the impression you're not very familiar with this subject. THERE IS NO ELECTRICAL RESISTANCE. In the early 1900s physicists discovered that some materials would conduct without electrical resistance if they were cooled to 0 degrees Kelvin (or -459.67 degress Fahrenheit, or -273.16 degrees Celsius. Incidentally, it happens that a degree Kelvin is equivalent to a degree Celsius. The only difference is one of calibration; zero on the Celsius scale is the freezing point of water at sea level. Had enough remedial education yet? ;-) ). That's why superconductors were named "superconductors." A hundred or so years ago superconductivity was an interesting finding but not very useful because cooling materials to their superconducting threshold was so energy intensive. They remained mostly a curiosity until 1987, when materials were discovered that conducted electricity without resistance at temperatures tens of degrees above absolute zero. These were called "high temperature superconductors." Since then even higher temperature superconductors have been discovered; the present record stands at 138K (or -135C, or -211F) Here is the chemical composition of the leader: Hg0.8Tl0.2Ba2Ca2Cu3O8.33 (Sorry, if I knew how to force the display of subscripts this sequence would be easier to read).

American Superconductor's first generation of products use a somewhat less effective compound made of Yttrium, Barium, Copper, and Oxygen (YBCO for short) that can superconduct up to around 93K. (or -180C or -292F) Their next generation of products will use a compound of Bismuth, Strontium, Calcium, Copper, and Oxygen (BSCCO for short) capable of superconducting up to around 110K.

No resistance kinda sounds like perpetual energy machine or cold-fusion to me.

Contrary to how it may seem, using superconductors does not give you a perpetual motion machine; for that you need more energy coming OUT of the system than what you put IN, which according to the laws of thermodynamics appears to be impossible. Suppose, for example, that you form a closed loop of superconducting wire and then feed an electrical current into it. As long as the wire remains cooled below it's threshold temperature the electricity will continue to rush around and around the loop without loss. As soon as you put some sort of device into the circuit (say, a standard 60W light bulb) the current will gradually be converted to heat and light by the bulb's filament until all the electricity is disipated.

So much for the fun facts. Why bother with superconductors? Because copper wires, as effective a conductor as they are, nevertheless lose a lot of energy due to their internal resistance, and the way things are going these days that is power the country needs. In addition, the superconducting wire AMSC is bringing to market can carry more than 100 times the current of an equivalently sized copper trunk line; you don't need as many superconducting cables to carry a given quantity of power, which (should) reduce maintenance costs. Finally, superconduting cable is easier to cool than copper; the former uses relatively cheap and abundant liquid nitrogen, while the latter uses a light oil (copper cables have to be cooled because the energy lost as electrical resistance manifests itself as heat; it is tremendously inconvenient for power companies to have their equipment starting itself on fire in the course of providing electricity).

The first major test of AMSC's wire begins this summer. Detroit Edison is in the process of pulling 18,000 lbs of copper power cables out of nine conduit tunnels and replacing them with 900 lbs of superconducting wire in three tunnels (Those figures are from memory. If someone knows better please correct me). The remaining six tunnels can be used for more superconduting cable or for high speed fiber optics. It will be interesting to see what effect using superconducting cable has on cost and reliability. All us AMSC longs hope for a smashing success. Of course.

Beyond power transmission lines, AMSC is also developing electrical motors that use HTS wire. They have successfully tested a 1,000 HP unit, and are working on a 5,000 HP unit. The eventual goal is a 33,000 HP motor the US Navy wants to use for ship propulsion.

The following link is a good place to start teaching yourself more about superconductors, if you are so inclined.


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