American Superconductor has begun work on a 138 kV high temperature superconducting (HTS) transmission cable on Long Island. At nearly 800 m, the cable will be the world’s longest and highest-voltage superconductor system and will be the first installed in a live grid.
The project is being undertaken by a government-industry partnership with local utility the Long Island Power Authority (LIPA) providing the site engineering and preparation, other partners include Nexans and Air Liquide.
American Superconductor is providing project management, technical input and is also the supplier of the HTS wire for the cable. Nexans is the cable and cable termination supplier, providing the development engineering and qualification of the cable, cable cryostat and terminations. Air Liquide is the cryogenics partner, providing the refrigeration system modifications, system engineering and installation support for the project, which, it is claimed, will carry more power than all previous high temperature superconductor (HTS) cable demonstrations combined.
The cable will be installed by early 2007 along LIPA’s Holbrook transmission right of way.
After an initial operational period and following performance and economic reviews of the cable system, LIPA plans to retain the new superconductor cable as a permanent part of its grid. LIPA and American Superconductor have also discussed plans to install high capacity, low-environmental-impact HTS cables elsewhere in the LIPA grid to address growing power demand.
The demonstration project, one of three being co-funded by the US Department of Energy, aims to enable HTS cables to be operated effectively in a power grid at transmission voltages.
Greg Yurek, chief executive officer at American Superconductor observed: “With a wide variety of commercial and demonstration projects underway, HTS wire has emerged from the laboratory and is poised to become a major force in the world’s electric grids.”