Fingrid prepares for the connection of Olkiluoto 3 to the national grid

According to the updated schedule of the supplier of the Olkiluoto 3 (OL3) reactor unit that is under construction in Eurajoki, the unit’s regular power production will begin at the end of 2018. Transmission system operator Fingrid and nuclear power company Teollisuuden Voima (TVO) have begun preparations to connect Olkiluoto 3 to the national grid. The connection requires special arrangements, because once completed, OL3 will be considerably larger than previous electricity production units, with a rated net capacity of 1,600 megawatts.

Finland’s power system can withstand the failure of a power plant of 1,300 megawatts. Fingrid and TVO had made a preliminary agreement already during the planning of the OL3 reactor unit concerning so-called system protection, whereby the reactor unit could be connected to the electricity system. In technical terms, the arrangement means that when OL3 is disconnected from the grid, industrial consumption will be restricted in close to real time such that the disturbance in the electricity system would remain within the allowed 1,300 megawatt limit.

Fingrid and TVO have now agreed on the practical implementation of system protection for Olkiluoto 3. The agreement was preceded by an assessment by the competent authorities, which ensured that implementation of the system protection does not have an impact on Fingrid’s handling of system responsibility under the Electricity Market Act. Next, an open competitive bid for industrial consumption included in system protection will be realised.

In addition to system protection, the connection of OL3 to the national grid is being prepared for by reducing electricity import capacity from Sweden by 300 megawatts via northern AC connections and by increasing the volume of Fingrid’s fast disturbance reserve.

As the transmission system operator with system responsibility under the Electricity Market Act, Fingrid must ensure the technical functioning of the electricity system and the upholding of national system security. The reliability of system protection and the sufficiency of its loads are prerequisites for upholding the security of the electricity system.

Further information:
Jussi Jyrinsalo, Senior Vice President, Customers and Grid Planning, tel. +358 (0)30 395 5118 or +358 (0)40 550 2044
Petri Parviainen, Customer Manager, tel. +358 (0)30 395 5282 or +358 (0)400 527 706