April 2001

Superconductor Power

By Technology Review

Some of the blackouts that struck California this winter might have been avoided if power companies could more quickly move large amounts of electricity between regions. Such a boost may be possible with a new type of superconducting tape invented at Los Alamos National Laboratory's Superconductivity Technology Center. Made from nickel alloy, the tape is coated with fine layers of zirconia using a pulsed-laser process that precisely orients the zirconia grains after deposition. Then subsequent layers of nickel are applied to create a superconducting film as thin as six micrometers. The tape carries one million amperes per square centimeter of current, about 14 times the capacity of today's bismuth-based superconducting tape and 200 times better than copper wire. The liquid-nitrogen-cooled tape can operate at a relatively balmy -196 C, making it far more economical than many existing high-capacity tapes that require cooling by liquid helium at temperatures as low as -269 C. The new process is also much faster than earlier methods. Within two to three years the tape should appear in products including transformers, electric motors and transmission cables. -V. Herrera