Researchers are on the cusp of applying superconductors to a range of civilian and military technologies.

They could dramatically boost the efficiency of everything from Navy destroyers to the wires that bring electricity into homes and businesses.



Superconductors – as Onnes’ discovery is known – are being tested as a way to dramatically cut the risk of widespread blackouts.



“It’s going to work; it’s really going to work,” says an enthusiastic Robert Hawsey, director of the Oak Ridge National Laboratory’s Superconductivity Technology Center. Fiber optics took 20 years to emerge from the lab to become the backbone of today’s information superhighway, he notes. After nearly 20 years of development, a new generation of superconductors are about to emerge from the shadows into large-scale applications.



Superconductors have a number of properties that endear them to high-tech visionaries. They have virtually no electrical resistance. In principle, once electricity begins flowing in a superconducting loop, it can flow almost forever. They carry larger amounts of electricity than standard wires and cables with similar dimensions. So superconducting components can be far smaller than their conventional counterparts.



For example, a conventional electric motor for driving a single Navy destroyer propeller might weigh as much as 200 tons, notes Scott Littlefield, director of ship science and technology at the Office of Naval Research (ONR) in Arlington, Va. A superconducting motor, in contrast, would tip the scales at 75 tons.



And superconductors don’t lose their electricity to heat. Thus a superconducting motor or computer chip is vastly more efficient than its conventional counterpart.



But there are drawbacks. Superconductors are more finicky than standard electrical components. If the current it carries or the magnetic field it encounters is too strong, a superconductor turns into a mundane conductor faster than Cinderella’s coach reverted to a pumpkin.



Then, there’s the problem with refrigeration. To get his superconductor to work, Onnes used liquid helium at 4 Kelvin (4 degrees C) above absolute zero – the point where molecules stop moving. By the mid-1980s, traditional superconductors had moved into niche markets. But the high cost of cooling them to liquid-helium temperatures was a stumbling block to broader applications.



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