Already in use on four continents in a broad range of harsh climates, 3M ACCR (aluminum conductor composite reinforced) has been installed now in Siberia, serving one of the region's largest cities, Irkutsk.

Irkutsk Electronetwork Co. (IESK) chose the overhead conductor as a way to avoid tower construction or right-of-way expansion while nearly doubling power transmission to the city's central district, where growing demand was putting a severe strain on capacity, according to the utility.

3M ACCR is a lightweight, low-sag, high-capacity conductor that can carry twice the current or more of conventional steel-core conductors of the same diameter, on existing towers, thereby helping utilities circumvent problems in crowded urban settings and environmentally sensitive areas. Its low-sag characteristic also provides a solution for clearance issues.

In Irkutsk, the 110-kV line raises capacity to 1,600 A on the link between a local hydropower plant and the Tzimlyanskaya substation, and to 1,240 A on the Tzimlyanskaya-Kirovskaya substation link. The 3M ACCR line replaced conventional steel-aluminum conductors.

The utility considered the option of increasing capacity by building a parallel line, but determined that acquiring the land and constructing the towers would be prohibitively expensive and difficult because of the crowded urban area. Installing larger aluminum-steel conductors would have required rebuilding the existing towers to bear the heavier weight.

Irkutsk is a city of about 600,000 residents, in the Irkutsk Oblast (administrative district), approximately 2,600 miles (4,184 km) east of Moscow. Its midwinter average daily mean temperature is about 0°F (-17.8°C). The city plays an important role in aircraft manufacturing and metals smelting.

3M ACCR also is operating in installations by utilities in Moscow and several other Russian locations, as well as in China, India, Brazil, Canada, Western Europe and the United States.

For more information, visit www.3M.com.