Utility companies worldwide are striving to reduce the life cycle costs of their medium voltage distribution systems in response to economic and environmental drives. The use of tree retardant XLPE insulation has allowed utilities to achieve long cable service life under severe operating conditions. This has lead to improved life cycle economics and minimized social and environmental issues resulting from cable replacement activities.
This paper will discuss the multitude of accelerated cable aging tests, implications and current global trends for both the TR-XLPE and the Copolymer XLPE insulations. It will review the experience with TR-XLPE in North America, experience with Copolymer XLPE and TR-XLPE in Europe as well as the growing interest and usage of TR-XLPE in Asia and LatinAmerica. As the long life performance expectations for the MV underground cable system increase, TR-XLPE increasingly is used as the insulation of choice to achieve these objectives.