Aurora Line Power Transmission Connection to Be Commissioned on November 13
The new 400-kilovolt Aurora Line transmission connection between Finland and Northern Sweden will be commissioned as early as November 13, 2025. Previously, the connection was expected to be ready for commissioning at the end of the year. Aurora Line is the most significant investment in Finland’s transmission grid this decade. Supported by substantial European Union CEF funding, the connection strengthens electricity transmission between the countries and improves electricity adequacy.
The 380-kilometer-long transmission line, running from Pyhänselkä in Muhos, Finland, to Messaure in Sweden, will more strongly integrate Finland’s electricity system into the Nordic grid and increase transmission capacity between Finland and Northern Sweden.
“Aurora Line will increase the cross-border transmission capacity to a maximum of 1,900 megawatts in both import and export directions. The available capacity will vary depending on the real-time state of the electricity system. Factors affecting this include the regional distribution of electricity production and consumption, the operational status of other interconnections, and the transmission line’s capacity, which depends on temperature. Transmission capacity can be utilized most efficiently when production and transfers between regions are balanced from the grid’s perspective, and no bottlenecks occur in individual grid sections,” says Fingrid’s Senior Vice President of Power System Operations, Tuomas Rauhala.
Aurora Line to Be Commissioned in Phases – First Without Series Capacitor
The Aurora Line connection will be commissioned ahead of schedule, benefiting the market and improving electricity adequacy already this year. This is made possible by a technical arrangement found by Fingrid and the Swedish transmission system operator Svenska kraftnät, allowing Aurora Line to be taken into use before the series capacitor on the Swedish side is completed.
A series capacitor is an electrical device integrated into the transmission line that improves the line’s transmission capability, especially over long distances, and enables large electricity transfers with lower losses. The series capacitor will be completed as planned during December, and its commissioning will enable better utilization of Aurora Line’s full transmission capacity, reducing capacity fluctuations. Before the series capacitor is ready, the capacity will fluctuate more depending on the grid’s operational situation.
Capacity Availability Will Increase Gradually
Aurora Line will significantly increase the cross-border transmission capacity and may, in certain situations, cause bottlenecks in other parts of the grid in Finland and Sweden. Implementing internal grid investments is important to strengthen the grid and enable even more efficient and flexible use of cross-border capacity in the future.
Especially in 2026 and 2027, grid investments in Sweden will, once completed, help alleviate bottlenecks in transmission connections and further improve the usability of Aurora Line. Fingrid and Svenska kraftnät will later assess the possibilities of increasing the maximum cross-border transmission capacity as a result of these grid investments.
Further information
Tuomas Rauhala, SVP, Electricity System Operations, tel. +358 30 395 5197
Email addresses are firstname.lastname@fingrid.fi.