Superconducting agreement signed
Oak Ridge National Laboratory have announced an agreement, which will help utility providers meet growing demands for superconducting cables.
The agreement allows a superconducting wire manufacturer, SuperPower Inc. of Schenectady, N.Y., to use a technology developed at ORNL that can lower the cost of producing superconducting wires for more efficient transmission of electricity.
Superconductors, materials that have no resistance to the flow of electricity, are one of the last great frontiers of scientific discovery. Not only have the limits of superconductivity not yet been reached, but the theories that explain superconductor behavior seem to be constantly under review. In 1911 superconductivity was first observed in mercury by Dutch physicist Heike Kamerlingh Onnes of Leiden University. When he cooled it to the temperature of liquid helium, 4 degrees Kelvin (-452F, -269C), its resistance suddenly disappeared. The Kelvin scale represents an "absolute" scale of temperature. Thus, it was necessary for Onnes to come within 4 degrees of the coldest temperature that is theoretically attainable to witness the phenomenon of superconductivity. Later, in 1913, he won a Nobel Prize in physics for his research in this area.
The next great milestone in understanding how matter behaves at extreme cold temperatures occurred in 1933. German researchers Walter Meissner and Robert Ochsenfeld discovered that a superconducting material will repel a magnetic field. A magnet moving by a conductor induces currents in the conductor. This is the principle on which the electric generator operates. But, in a superconductor the induced currents exactly mirror the field that would have otherwise penetrated the superconducting material - causing the magnet to be repulsed. This phenomenon is known as strong diamagnetism and is today often referred to as the "Meissner effect". The Meissner effect is so strong that a magnet can actually be levitated over a superconductive material.
In 1986, a truly breakthrough discovery was made in the field of superconductivity. Alex Müller and Georg Bednorz, researchers at the IBM Research Laboratory in Rüschlikon, Switzerland, created a brittle ceramic compound that superconducted at the highest temperature then known: 30 K. This discovery started a new era of so-called "high temperature superconductors". What made this discovery so remarkable was that ceramics are normally insulators. They don't conduct electricity well at all. So, researchers had not considered them as possible high-temperature superconductor candidates. The Lanthanum, Barium, Copper and Oxygen compound that Müller and Bednorz synthesized, behaved in a not-as-yet-understood way. (Original article printed in Zeitschrift für Physik Condensed Matter, April 1986.) The discovery of this first of the superconducting copper-oxides (cuprates) won the 2 men a Nobel Prize the following year. It was later found that tiny amounts of this material were actually superconducting at 58 K, due to a small amount of lead having been added as a calibration standard - making the discovery even more noteworthy.
Cooled by cheap and abundant liquid nitrogen, some high temperature superconductors can be used to make lighter, smaller, more efficient, higher capacity power devices; relieve congested power line networks; and increase power transmission capacity.
Second generation, also known as "2G" wires made by depositing high temperature superconducting materials onto inexpensive metal templates coated with ceramic buffer layers. This will make high temperature superconducting wires less expensive.
ORNL’s research on 2G wires includes the discovery of lanthanum-manganese-oxide as a buffer material that can be formed rapidly using commercial film-deposition processes.
“This agreement with SuperPower is a great example of ORNL working with industry and delivering the science and technology to help address the nation’s energy challenges,” ORNL Director Thom Mason said.
Superconducting agreement signed