Contract signing for Corinth-Attica 400 kV Transmission Line

Contract signed with MYTILINEOS - ATERMON consortium for the new 400 kV Transmission Line connecting the new Corinth Ultra High Voltage Center with the Koumoundouros UHVC in Attica.

On Tuesday, February 6, the signing ceremony of the construction contract for the new 400 kV Overhead Transmission Line took place at the offices of the Independent Power Transmission Operator (IPTO). This line will connect the new Corinth Ultra High Voltage Center with the Koumoundouros Ultra High Voltage Center in Attica. The total budget for the project is 77,02 million (plus VAT), and the contractor is the consortium of MYTILINEOS and ATERMON.

The commissioning of this project - expected in the first half of 2026 - will mark the conclusion of the so-called "Eastern Corridor" (Megalopolis-Corinth-Attica), completing the connection of the Peloponnese to the Ultra High Voltage System.

The contract was signed by Mr. Manos Manousakis, Chairman and CEO of IPTO, Mr. Kostas Horinos, Executive Director M Power Projects at MYTILINEOS, representing the consortium leader, and Mr. Ioannis Samaras, Chairman and CEO of ATERMON.

The new 400 kV Transmission Line between Corinth Ultra High Voltage Center and Koumoundouros Ultra High Voltage Center, approximately 86 km long, is a project of particular significance. Its operation will significantly increase the capacity of electricity transmission between the Peloponnese and Attica, which until now have been exclusively connected by 150 kV lines. It will significantly improve voltage stability in the Southern Greece power system and enhance security of supply, ensuring the Peloponnese under any combination of load generation. Finally, it will strengthen operational security under conditions of increased penetration of Renewable Energy Sources into the Transmission System.

The project is co-financed by the Recovery and Resilience Fund “Greece 2.0” with funding from the European Union’s instrument Next Generation EU, as a project οf general importance for the country's economy. It is combined with the upgrade of the Koumoundouros Ultra High Voltage Center (contracted to MYTILINEOS), which will serve the connection of the Eastern Corridor and is also co-financed by the Recovery Fund.

Mr. Manos Manousakis, Chairman and CEO of IPTO, stated: "With the new ultra-high voltage line Corinth-Attica entering construction phase, IPTO completes the 'Eastern Corridor,' a critical electrical infrastructure that resolves once and for all the issue of energy security in the Peloponnese. In combination with the 'Western Corridor, which is already in operation, the Peloponnese will have a double connection at 400 kV, with significant benefits for the potential of green energy production. The project will overall strengthen the terrestrial Transmission System with new, state-of-the-art infrastructure, such as the Ultra High Voltage Center in Corinth, which in the coming years will become the starting point for the electrical interconnection of the Dodecanese with mainland Greece."

Representing MYTILINEOS, Mr. Kostas Horinos, Executive Director of M Power Projects, emphasized: "MYTILINEOS, following international trends for efficient electricity transmission and distribution, strategically invests in network development and undertakes significant projects for IPTO, having already completed the new Overhead Ultra High Voltage Electricity Transmission Line between Greece and Bulgaria (New Santa-Maritsa East). We are proud to contribute to IPTO's national effort to develop domestic Renewable Energy Sources through the extension and upgrade of its system and electricity market development."

The Τhe first part of the Eastern Corridor, namely the 400 kV Transmission Line between Megalopolis Ultra High Voltage Center and Corinth Ultra High Voltage Center, was completed in May 2023. Since the spring of 2023, the "Western Corridor" (400 kV Overhead Transmission Line Megalopolis-Patra-Acheloos) has been in full operation, representing the first major step towards the enhancement of the energy security of the Peloponnese.