Elering energised the Viru-Tsirguliina electricity connection, which is essential for synchronisation

Elering has successfully completed the reconstruction work on the Viru-Tsirguliina 330-kilovolt overhead transmission line, which constitutes a part of the major project for synchronisation with Continental Europe. This is one of the largest and most important physical infrastructure objects in Estonia that is required for synchronisation. The connection was energised on 5 November.

Work on the reconstruction of the line commenced in June 2023 and was completed in October 2024. As of now, maintenance and cleaning work is partially ongoing. Within the framework of the project, the 244-kilometre high-voltage overhead transmission line was overhauled, including the replacement of the outdated Soviet-era line cables and towers with modern ones. As a result of the reconstruction, approximately 50 hectares of land were reclaimed from the protection zone.

At peak times, approximately 250 contractors were working on the project throughout the length of the line. On the Viru-Mustvee line section, 257 towers were erected, while 469 towers were erected on the Mustvee-Tsirguliina section. A total of 726 towers were erected for the 330-kilovolt line. The main contractors Leonhard Weiss OÜ and Enersense AS performed the construction work.

Hannes Kont, Head of Project Management and Director of the Synchronisation Program of Elering, explained that after disconnecting from the Russian electricity system, the Baltic countries must maintain a reinforced north-south electricity connection. “The multitude of transmission lines and high transmission capacity provide us with assurance that a domino effect of lines switching off or becoming completely separated due to excessive loads will not come about,” explained Kont.

He added that with the commissioning of the Viru-Tsirguliina connection, all the major infrastructure investments have been made. The completion of the control and monitoring systems is still pending, after which an isolated operation test and disconnection from the Russian electricity system will take place.

On 8 February, the system operators of the Baltic countries will desynchronise the Estonian, Latvian and Lithuanian electricity systems from the Russian synchronous area. This will be followed by an isolated operation test in the course of which the capacity of the electricity systems of the three Baltic countries will be evaluated. Synchronisation with the Continental European frequency area is planned to take place on 9 February 2025.

The total cost of Viru-Tsirguliina was approximately 86.5 million euros. The Connecting Europe Facility (CEF) of the European Union will cover 75 percent of the investments of the major project for synchronisation. The remaining 25 percent is covered from the funds of congestion income in Estonia.