A surge protector to end all surge protectors
In order to do this, however, the superconductor must be super cooled to -460 F. According to Jason Fredette, director of corporate communications for American Superconductor, when a large fault current travels through the grid, the superconductor cable heats up and stops conducting, effectively suppressing the power surge. “The wire itself can act as a smart switch,” Fredette said. What makes IFCL-HTS cable unique is that it operates at a higher temperature than traditional superconductors, -320°F, which makes it more practical for use. American Superconductor and its partner Southwire Company developed a 25-meter IFCL-HTS cable that was tested at Oak Ridge National Laboratory (ORNL) in 2009. According to Dr. Christopher Rey, senior staff scientist at ORNL, the lab plans to test an improved version in the near future.
In addition to preventing surges, the IFCL-HTS cable can improve electrical service to dense urban areas, according to David Lindsay, director for distribution engineering at Southwire Company. Superconductor cables can carry up to ten times more electricity than a typical copper cable, and superconductor cables transmit electricity with near zero resistance. The added capacity and efficiency is useful for large cities such as New York, where electricity demand is rising and underground space to run additional cables is limited.
The fault current-limiting superconductor cables are best suited for urban markets, according to Lindsay. In rural areas, he explained, it would likely be more affordable to use overhead power lines and other solutions to suppress power surges. As developmental testing of the cable concludes, HSARPA will explore the possibility of installing the IFCL-HTS technology in a selected location in the electric grid for an operational demonstration, according to Mahmood.
Another aspect of DHS’s Resilient Electric Grid project focuses on developing a stand alone fault current-limiting device that can be installed anywhere on the existing electric grid, according to Mahmood. DHS is collaborating with Silicon Power to develop a Solid State Current Limiter. A semiconductor switch in the device suppresses power surges in electric cables. The technology would allow utilities to incorporate surge protector capabilities into the infrastructure without replacing current cables or existing protection schemes. DHS is scheduled to hold a demonstration of that technology’s key elements at the KEMA, Inc. testing facility in Chalfont, Penn. in the fall of 2010.
These solutions would protect critical infrastructure dependent on electrical power from blackouts that not only threaten safety, but commerce as well.
Power outages cost the nation approximately $100 billion a year, according to HSARPA. Having a resilient electric grid will protect Wall Street and other financial centers from power outages, according to Fredette. “If New York City goes black, that damages our economy,” he said. “This project employs superconductor technology to protect our nation’s financial centers.”
