Impact of gradually replacing old transmission lines with advanced composite conductors

Driven by higher energy demand, the complications of finding new corridors, construction, and slow commissioning procedures for transmission lines, an advanced technology has been innovated to adapt to the modern power system's needs. A new type of overhead conductor with a polymer composite core (ACCC) have a greater ampacity, lower sag, and are lighter than traditional ACSR conductors. Therefore, it is this innovative technology is optimal choice when the decommissioning of old lines takes place. This paper analyzes the impact of the gradual replacement of old transmission lines with all the benefits and disadvantages. It addresses the issues of equipment aging and proposes a replacement strategy for a cost-effective transition to a modernized power system functioning at improved performance. Calculations and analyses are performed on a real interconnected system, composed of several South East European (SEE) transmission grids.