A third 400 kV AC interconnection to Sweden

The transmission system operator Fingrid Oyj is, in cooperation with the Swedish transmission system operator Svenska kraftnät, planning a new transmission line from Pyhänselkä in Muhos via Keminmaa to Messaure on the Swedish side of the border.

The background for the transmission line project is electricity market needs for additional capacity between Sweden and Finland. Cross-border capacity between the countries is often inadequate, which means that the electricity market cannot function efficiently and electricity prices diverge. In an import situation, this increases the price of electricity in Finland. Furthermore, insufficient connections endanger adequacy of electricity in Finland during exceptional situations.

In 2016, Fingrid and Svenska kraftnät completed a study on cross-border capacity development needs. According to the report, electricity transmission connections between Finland and Sweden are inadequate and so-called bottleneck situations are very likely also in the future, so a new transmission connection is needed. Various options for increasing electricity transmission capacity were examined, and a new alternating current connection from northern Finland to northern Sweden appeared to be the most feasible in terms of the socio economic benefit and also technically. On 23 August 2017, Fingrid and Svenska kraftnät signed an agreement concerning the realisation principles for the new connection.

Status as Project of Common Interest

The project has been granted with Project of Common Interest status on 23.11.2017. Status can be granted to projects which are deemed essential to the integration of the European energy markets and to achieve energy policy goals of the EU. Third AC interconnection between Finland and Sweden promotes all main goals of the EU energy policy; affordable, sustainable and secure energy.

The project has been granted with Connecting Europe Facility (CEF) support of 4.325 million euros for studies. Fingrid and Svenska kraftnät will apply together CEF-funding also for the construction phase. The national energy regulators of Finland and Sweden have made Cross Border Cost Allocation (CBCA) decision on the project in March 2020.

PCI numbers and descriptions are:

4.10 Cluster Finland – Sweden [currently known as "Third interconnection Finland – Sweden"], including the following PCIs: 

• 10.1 Interconnection between northern Finland and northern Sweden
• 10.2 Internal line between Keminmaa and Pyhänselkä (FI)

Learn more about PCIs.

Project location and planning situation

The connection between Finland and Sweden will be implemented in two phases. At first, the section between the Pyhänselkä substation in Muhos and Keminmaa (PCI 4.10.2) will be completed. In this phase also existing Pyhänselkä substation will be expanded and a new Viitajärvi substation will be built to Keminmaa. In second phase new transmission line will be built from Viitajärvi substation to Messaure substation in Sweden (PCI 4.10.1). New line will cross the border between Finland and Sweden at Tornio-river in Vuennonkoski (FI)/Risudden (SE).

Figure 1. The planned route of the transmission line in Finland and the route alternatives being analysed in Sweden. Total length of the transmission link is about 380 km. 

The Environmental Impact Assesment (EIA) procedure was finalized in January 2019 for the section between Muhos and Keminmaa and between Keminmaa and the Swedish border in June 2020. Environmental studies will continue in Sweden during 2021. Fingrid and Svenska kraftnät have agreed to fix Vuennonkoski (FI) and Risudden (SE) as the crossing point of border line.

General design of the overhead transmission between Pyhänselkä and Viitajärvi substations is going on, and same design work for Viitajärvi-Vuennonkoski/Risudden-Messaure will be started by summer 2021.

Large scale construction work is aimed to be starting between Pyhänselkä and Viitajärvi in autumn 2022. In addition to line construction also extensions to Pyhänselkä and Messaure substations and Isovaara series compensation station will be built. In Finland also new Viitajärvi substation will be constructed in municipality of Keminmaa and new Isomaa series compensation station.

The common goal of Fingrid and Svenska kraftnät is to have the transmission line connection in use by the end of 2025.

Abstracts of EIA-reports

Abstract of Pyhänselkä-Keminmaa 400 kV transmission line EIA-report (Finnish)

Abstract of Keminmaa-Tornionjoki 400 kV transmission line EIA-report (Finnish)