Published on December 2nd, 2009 | by Tina Casey4
New Superconducting Magnet Breaks Records with a Lower Carbon Footprint
Florida State University has just announced that it is chipping in $1 million toward the cost of a $3 million magnet to be constructed at the National High Magnetic Field Laboratory. The new high tech magnet is expected to generate a field about 45% more powerful than the strongest superconducting magnet currently available, or roughly 3,000 times stronger than an ordinary refrigerator magnet.
Behind that strength is a sustainable purpose: the new magnet will be made of a high-temperature superconductor that is more energy efficient and far less expensive to operate than its conventional counterparts. If it proves successful – and researchers at the lab have every expectation that it will be – it could mark the beginning of a new generation of super powerful magnets that help lower both the cost and the carbon footprint of scientific research.
The Trouble with Low-Temperature Superconducting Magnets
Until now, superconducting magnets have required a low temperature to operate, which in turn requires expensive coolants such as liquid helium. There’s another catch: conventional superconductor materials stop working if the magnetic field exceeds 23 tesla (a tesla is a unit of measurement for the strength of magnetic fields). That’s no problem for hospital MRI machines and similar equipment, which operate at no more than 3 tesla. But it puts a severe crimp in scientific research. To get around it, researchers can use resistive magnets made of non-superconducting materials, but these require far more electricity to operate. To say nothing of the carbon footprint, the expense is a significant burden, well over $700 per hour for a typical resistive magnet.
The New High-Temperature Superconducting Magnet
The new magnet has been developed in collaboration with industry partner SuperPower Inc., a global specialist in superconductors. It will use about 5 miles of cable made of a superconducting material called yttrium barium copper oxide (YBCO). YBCO can operate in magnetic fields higher than 23 tesla, and in fact the new magnet is expected to achieve 32 tesla. YBCO does not require a low operating temperature, and once brought up to speed it requires little or no electricity. It also creates a more stable field than resistive magnets, making it a more dependable source for data in scientific research at the high end of the tesla scale.
Magnets and Research
Researchers expect that the new magnet will make the old resistive magnets obsolete in physics research. In practical terms that means potential advances in medical diagnostic equipment, studies of protein structure, and the physics of semiconductors and metals. It could also have implications for the use of magnets in new sustainable technologies from small hand-held battery powered devices on up to battery powered cars – and perhaps beyond.
Image: Magnetic toy by Karl Horton on flickr.com.