​​​The Core Regulated Activity of Transmission and specifically the Transmission System Owner, is one of the three Units of the Network Business Unit and is responsible for the planning, specifications, technology and construction work related to the operation and maintenance of the Transmission Network, with the objective of responding to the ever-increasing need for electricity while maintaining the reliability of the Transmission System.

The Transmission Network is the backbone of the EAC's electricity system, connecting the Power Stations to the Distribution Network.

According to the Transmission and Distribution Rules, Transmission begins from the busbars of the Transmission Substations that are housed in the Power Stations and via 132 kV or 66 kV overhead power lines or underground cables reaches the 11kV or 22 kV Medium Voltage switchgear in all the other Transmission Substations that are usually located within the load centres.

For operational reasons, the Transmission System Owner Unit is divided into the following activities: Transmission Substations, Overhead or Underground Transmission Network, Protection and Technology, System Studies, Area Offices-Transmission.​