Sapphire fibers carry 40 times more electricity than copper wire
By Ben Coxworth
September 9, 2011
One of the limitations of traditional copper electrical wiring is the fact that the metal's resistance causes the wire to heat up, and some of the energy being carried through the wire is lost in the form of that heat. Wires made from superconducting materials, however, would have no resistance, so could transfer much more energy. While previous attempts at the technology have proven too fragile or expensive, researchers from Tel Aviv University have now developed a new type of cost-effective superconductive wire, that they claim can carry 40 times more electricity than copper wiring of the same size.
Earlier efforts at superconductive energy transfer have involved coating crystal wafers and magnetic tapes with superconductors, but were respectively too brittle and too expensive.
The Tel Aviv team instead created wires made from single-crystal sapphire fibers, which were then coated in a ceramic mixture. Each wire is slightly thicker than a human hair, and although they can transfer large amounts of electricity, they must be continuously cooled in order to remain in a superconducting state. That duty is handled by a self-contained cooling system, that uses inexpensive liquid nitrogen.
Dr. Boaz Almog, one of the scientists who developed the superconductive wires, believes that they would be ideal for delivering energy from remote renewable energy sources, or for deploying electricity throughout municipal grids.