Prior to launching the planning procedure, Elering analyzed various possible route corridors both onshore and offshore. Based on the results, Elering concluded that Aulepa is the optimal landing point for EstLink 3. Consequently, Elering applied for the initiation of a national special spatial plan for a new 330 kV overhead line, which will connect the EstLink 3 subsea cable with the existing transmission network at the Rehemäe substation. During the planning process, alternative routes for the Rehemäe–Aulepa 330 kV overhead line will be identified, the best option selected, and an environmental impact assessment conducted.
In connection with the construction of the EstLink 3 subsea cable, the existing grid will also need to be reinforced at various locations across Estonia. In addition to building the new line between Rehemäe and Aulepa in western Estonia, existing 330 kV overhead lines will be reconstructed between Kiisa and Rakvere, Rakvere and Püssi, Paide and Sopi, and Sopi and Sindi. Furthermore, a new high-voltage substation will be established in Tallinn, which will be connected to the Aruküla and Kiisa 330 kV substations via new overhead lines.
The new overhead line will be constructed to accommodate the full capacity of EstLink 3 and, if necessary, additional capacity from future offshore wind generation areas around the larger Estonian islands.
The planned transmission capacity of the EstLink 3 direct current (DC) connection is 700 megawatts (MW).
Background Information:
The transmission system operators (TSOs) of Estonia and Finland signed a memorandum of understanding on 28 June 2022, agreeing to commence work on the establishment of EstLink 3.
EstLink 3 will consist of a DC cable connecting Estonia and Finland and converter stations located at both ends of the cable. On the Estonian side, the planned EstLink 3 project comprises a DC subsea cable, an onshore cable, a converter station near Aulepa in Lääne-Nigula municipality, and a new 330 kV overhead line between Rehemäe and Aulepa, connecting EstLink 3 to the existing 330 kV network in western Estonia.
This connection will further strengthen security of supply, contribute to achieving climate and energy policy goals, and more closely integrate the Baltic States and the Nordic countries into a single market area.
EstLink 3 is designated as a project of common interest (PCI) by the European Union and is planned to be financed through EU funds and congestion revenue (interconnection capacity revenues), meaning its construction will not lead to an increase in the overall electricity price for consumers.
Currently, Estonia has two electrical interconnections with Finland: EstLink 1, with a capacity of 350 MW, connected to the Harku substation in Estonia and commissioned in 2006; and EstLink 2, with a capacity of 650 MW, connected to the Püssi substation and commissioned in 2014.
Further information about the connection: https://elering.ee/estlink-3