Baltic countries ready for ENTSO-E synchronization

• Baltic countries notify Russia and Belarus of intention to unplug from BRELL area
• ENTSO-E synchronization scheduled for early 2025 to link Baltic countries to continental Europe
• Poland, Baltic countries working on backup line

BUCHAREST (ICIS)–The three Baltic countries Estonia, Latvia and Lithuania, are preparing to synchronize with the European Network of Transmission System Operators for Electricity (ENTSO-E) system early next year as they are taking the final steps to decouple from the Russian and Belarusian grids.

Their electricity transmission system operators Elering, AST and Litgrid, have already notified Moscow and Minsk of their intention to unplug from the BRELL area (Belarus, Russia, Estonia, Latvia and Lithuania). The deadline to send the notification was August 7.

The BRELL agreement under which they had been connected with Belarus, the Russian exclave of Kaliningrad and Russia itself since Soviet days is due to expire on February 7 2025 and the three Baltic operators are planning to disconnect from it altogether the following day.

The interconnection with the Continental Europe Synchronous Area has been scheduled for February 9.

The interconnection with the continental grid operating under the umbrella of the ENTSO-E is considered of strategic importance for the three countries and will be carried out through the 400kV LitPol link, connecting Lithuania and Poland.

The line is currently operational and has a bidirectional transfer capacity of 500MW.

However, once the synchronization is completed, fully aligning the three Baltic countries with the European grid, the capacity is expected to increase.

The capacity that could be made available for commercial exchanges is yet to be decided.

SYNCHRONIZATION TESTS

Lithuania is connected with Latvia, which is in turn connected with Estonia. The three Baltic countries are expected to carry out preliminary tests before completing the synchronization.

Lithuania and Estonia are connected via back-to-back lines with Sweden and Finland respectively. The aggregated capacity of the two lines to Finland and one line to Sweden is 1.7GW. Synchronization is to take place via the LitPol line, with other countries synchronizing through the Lithuanian system to which they are connected.

Susanne Nies, energy expert at Helmholtz Zentrum Berlin, a Germany-based think tank, told ICIS that the test would involve decoupling from the grids of Belarus, Kaliningrad and Russia itself and operating in full isolation for a period of time.

The island mode test is required to ensure the countries can operate at a stable frequency of 50Hz in conditions of peak winter demand. The three Baltic countries’ aggregated peakload capacity is around 4.5GW and their baseload capacity is around 1.68GW.

Lithuania, Latvia and Estonia were fully prepared for the island mode test, according to Nies, having deployed all the necessary infrastructure and IT systems needed to strengthen and stabilize the grids ahead of the synchronization.

She added that Kaliningrad, which becomes an island after synchronization, has passed two tests successfully and can be fully self-sufficient, providing electricity supplies to its one million people from two combined cycle gas turbine power plants.

Nies, who has been following the Baltic project since it was launched in 2015, said the purpose of the synchronization with ENTSO-E was primarily to guarantee security of supply rather than commercial exchanges.

For now, the existing line will be exempt from the EU’s 70% rule, she added, which enters in force in 2025 and requires electricity grid operators to make available 70% of the transmission capacity for cross-border trading.

BACKUP

There is also a need to build an additional line to ensure that in case of risks to the existing connecting infrastructure or generating capacity in the Baltic area, the additional line would provide backup, Nies added.

The Baltic operators and their Polish counterpart, PSE, are now considering whether the backup line should be built along railroad or motorway connections, both of which are being developed between Poland and Lithuania.

Nies said plans to build the Harmony Link, a subsea cable connecting Lithuania to Poland, were no longer being considered amid security fears following suspected attacks on subsea energy infrastructure in the Baltic Sea in recent years. High-voltage line solutions have also become more expensive.

Baltic synchronization has been supported by the EU, with funding from the Connecting Europe Facility amounting to €1.2 billion and covering around 75% of the project’s eligible costs.