American Superconductor Corporation, a leading global supplier of superconductor products and power electronic converters for the electric power industry, today reported that Pirelli Energy Cables and Systems has delayed the demonstration of the three high temperature superconductor (HTS) cables Pirelli had installed last summer in a Detroit Edison substation. The delay is due to a vacuum system problem. Tests of sections of the installed cables have shown that the HTS wires used in these cables met all performance requirements for rigorous field installations.

In an advisory issued today, Pirelli indicated that the cable cryostats, which use a vacuum to limit the amount of heat entering each cable, are able to achieve only partial vacuum. Pirelli says more extensive testing of the cable system components is needed to determine what is keeping the cables from achieving full vacuum and to determine the steps and timeframe needed to correct the problem. Pirelli anticipates issuing a timetable for commissioning of the cable system in the second quarter of 2002.

"While we are disappointed with this delay in the cable demonstration project, we are pleased that our HTS wires met all performance specifications," said Greg Yurek, chief executive officer of American Superconductor. "Cryogenic piping installations that utilize vacuum thermal insulation have been in operation around the world for many years and we believe the vacuum problem in Detroit will not hinder future HTS cable installations. The demand to move larger and larger quantities of power through the grid continues to grow and we believe HTS power cables will play a significant role in meeting this demand."

The Detroit Edison Frisbie substation is the site of the first installation and demonstration of an underground HTS cable in a U.S. utility network. Three 400-foot cables were installed inside 4-inch-diameter underground ducts during the summer of 2001. All other cable components, including the cryogenic system, were completed in the fall of 2001.