15 April 2004 - 3M has expanded the field testing of its new high-capacity electricity transmission cable to include installations at the Western Area Power Administration's (WAPA) Liberty Substation near Phoenix, and at the Salt River Project's Santan Generating Station Expansion in the Phoenix suburb of Gilbert, AZ.

The cable, known as Aluminum Conductor Composite Reinforced (ACCR) from 3M, has been meeting expectations in on-going field tests at Oak Ridge National Laboratories in Tennessee, and at utility installations in Minnesota, North Dakota and Hawaii.

Designed to reduce electrical transmission congestion by increasing overhead electrical power-line capacity, the ACCR may help provide near-term solutions to the thermal bottlenecks afflicting the nation's power grid.

The heat-resistant cable, with its unique metal composite core, is capable of transmitting two to three times more electricity than conventional power-line cables of the same diameter, while not increasing mechanical stresses on the towers, or exceeding sag limits during peak thermal loads or heavy ice loads. As a result, it can be installed quickly on existing towers, requiring no additional rights of way.

The ACCR has undergone more than nine-and-one-half cumulative years of field operation so far, under conditions testing various cable sizes and constructions for high temperature, corrosion performance and ice and wind loading. The WAPA Phoenix installation will demonstrate performance of cable constructed with 3M's Composite Conductor as a core with three constructive layers of aluminum. The Salt River Project will demonstrate the high-temperature operation of the ACCR. The Valley Group's Cat 1 monitoring system will provide performance data at 15-minute intervals.