Estlink 3

Aulepa, a village in Lääne-Nigula parish on Estonia’s north-west coast, is the one fixed point on the map of Estlink 3 so far. That is where the planned cable would come ashore. Its Finnish end has not been published by the grid operators themselves, so the map marks the Finnish coast only approximately. Estonian public broadcaster ERR reported in January 2025 that the Finnish terminal would be at Inkoo, west of Helsinki, with a subsea cable of about 120 km.

The project dates from 28 June 2022, when Elering and Fingrid signed a memorandum of understanding to start planning a third subsea link between their countries. The two existing cables, Estlink 1 and Estlink 2, both run further east, from the Tallinn area and from Püssi.

Elering gives its reasons plainly on its Estlink 3 page: to harmonise electricity prices in Estonia and Finland, to bring larger volumes of cheap Nordic renewable power south, and to raise security of supply. Elering puts the capacity at 700 MW. The Wikipedia article on the Estlink cables cites “up to 1000 MW” from the 2022 announcement, so the size has moved during planning; the figures above follow Elering.

The paperwork is under way. Elering applied for a building permit in February 2024, and the environmental impact assessment began on 25 July 2024. The Estonian side also needs a good deal of new grid behind the landing point: a new 330/110 kV substation in Tallinn, new 330 kV lines, and reconstruction of the overhead lines on the Kiisa–Rakvere, Rakvere–Püssi, Paide–Sopi and Sopi–Sindi routes.

The marine section has its own assessment track. On 31 March 2025 Elering submitted the environmental impact assessment programme for the subsea cable for approval, with a public discussion at Sutlepa on 23 April. Because the cable crosses into Finnish waters, the procedure is transboundary. Elering expects the final report by 2027 and an investment decision in 2026–2027.

Money is the other condition. ERR put the total cost at about €1.1 billion, roughly €600 million of it Estonian, with half hoped for from the EU and the rest paid from interconnector congestion income.

Several things are still open. No voltage or converter technology has been published, the length and cost figures come from press reporting and not from the operators, and no final investment decision has been announced. The 2035 date comes from the 2022 memorandum. Given how long Estlink 1 took to go from talks to cable, a decade from memorandum to power flow is not a cautious schedule.

The immediate milestone is the outcome of the environmental assessment, due by 2027, which should also confirm on paper whether Inkoo is where the cable reaches Finland.