Underground Power Cables
Because of the fast growth in load densities in main towns and cities, 33 kV, 11 kV and LT underground cables are being used to meet the ever growing demand of electric power. The underground cable system has attained considerable significance in distribution networks. This is since in towns and cities, almost all roads are already occupied through LT, HT overhead lines, telephone lines, street lights, advertising boards and etc., on either side of the roads. In addition, high-rise buildings make it hard to go for overhead systems for sub-transmission or distribution. Therefore, the overhead system with bare conductors is prone to frequent breakdowns causing interruption in power supply. Uninterrupted power supply could be managed through employing underground cable ring system. The underground cabling system is particularly significant for metropolitan cities, city centres, airports and defence services.
Underground distribution costs are among 2 to 10 times in which of the overhead system. Yet, it is preferred because of elimination of outages caused through abnormal weather conditions such as rain, storms, snow, lightning, fires, stress, accidents, etc. Therefore, this system is environment-friendly and has a long life. In further, improved cable technology has decreased the maintenance cost of the underground system compared to the overhead system.