Elering signs last of four major contracts connected to synchronization project

Elering signed a 55.9-million-euro contract with Leonhard Weiss and Empower for the full renovation of the 330 kV high-voltage line between Tsirguliina and Viru substations. 

The construction works are planned to begin in 2023 and will be completed in 2025. This is the last of four major contracts under which Elering will renovate the powerful transmission lines originating in north-eastern Estonia and running to Latvia via Tartu and Valga and will establish three synchronous compensators.  

Chairman of the Elering management board Taavi Veskimägi said that the renovation of the Latvian connections is an important precondition for connecting Estonia and the Baltic states to the continental European electrical system. “We will renovate two older Estonia-Latvia connections so that one of the two connections would be constantly available during the works. In addition, in 2020 we completed a completely new Estonia-Latvia connection that essentially runs from Tallinn to Riga. Thus, in the near future we will constantly have use of two connections with Latvia, each with a substantial capacity, which will ensure both security of supply in Estonia, power trading between countries, as well as transmission of reserve capacities in the north-south direction, which will become more important following synchronization,“ said Veskimägi.

The length of the Tsirguliina-Viru overhead line to be renovated is 244 kilometres and the leads in the lines will be supported by 722 pylons. The line will pass through 12 municipalities in four counties. The route of the line will remain the same and the new pylons will be erected in the current locations. “Use of the existing corridor is the renovation solution that will pose the fewest socioeconomic and environmental impacts,“ said Veskimägi. 

The new pylons will predominantly support only 330-kilovolt leads, but on the north shore of Lake Peipus, in the Alajõe area, 110-kilovolt overhead lines will be installed on the same pylons for 15 kilometres. This will allow nine kilometres of 110 kilovolt line on separate pylons to be retired, freeing about 45 hectares of line corridor from restrictions. 

The wintertime capacity of the line will rise by one-third compared to current levels, and in summertime temperatures, it will almost triple. The planned service life of the line is 50 years. 

Elering will finance 75% of the renovation of the Tsirguliina-Viru high-voltage line from European Union assistance. As for the remaining 25%, Elering will use proceeds of auctions of transmission capacity. The renovation will not increase the network fees paid by Estonian power consumers. 

Preparations for connecting Estonia and the Baltic states to the continental European power system and frequency area must be completed by the end of 2025. In addition to renovating three powerful transmission lines, Elering will establish the synchronous compensators necessary for ensuring the stability of the frequency at three transmission grid substations and will renovate and improve the network’s monitoring and control systems. The total volume of investments related to synchronization will come to approximately 300 million euros.