A year off the BRELL grid: what Baltic synchronisation cost

A year ago this week Estonia, Latvia and Lithuania left the power system they had shared with Russia and Belarus since Soviet times and joined the continental European grid. The switch itself went without incident. The more useful question now is what the first year has cost and who is paying. The answer is less about wholesale electricity prices, which fell slightly in 2025, than about the price of keeping the grid's frequency stable, a service the Baltic states used to receive from the Russian system and now have to buy themselves.

What changed on 8–9 February 2025

The three grids disconnected from the BRELL ring on 8 February 2025, ran on their own for about a day, and synchronised with the Continental Europe Synchronous Area through Poland on 9 February. For the next nine months they operated in a trial mode while the European system operators checked frequency control and other parameters. On 28 November 2025 ENTSO-E announced that the Baltic operators, Elering, AST and Litgrid, met all key technical requirements and had moved to permanent synchronous operation on 25 November, joining the regional group of continental operators.

The investment behind this was large. The Estonian Competition Authority puts the total cost for the three Baltic states and Poland at about €1.6 billion, of which Estonia's share was €298 million, with EU funding from the Connecting Europe Facility covering up to 75 per cent. The money went into new and rebuilt lines, synchronous condensers that give the grid the inertia it previously drew from Russian generators, and control systems.

Prices did not rise over the year

Fears that synchronisation would push up wholesale prices have not been borne out on an annual basis. ERR reported that Estonia's average day-ahead price in 2025 was €80.39 per MWh, against €87.27 in 2024. Latvia averaged €85.31 and Lithuania €85.73. The difference between the Baltic states is small; the difference with Finland, at €40.48, is large, and it reflects Finland's own generation mix rather than anything to do with synchronisation.

The monthly pattern tells a more mixed story. February 2025 was Estonia's most expensive month, at €151.85 per MWh. At the time Elering attributed the week's price rise after the switch to less wind, colder weather and higher gas prices, not to the change of grid. The Estlink 2 cable to Finland was also out of service until midsummer, which limited cheaper imports. Even so, Estonia imported 46 per cent of its consumption from Finland in 2025, according to Electricity Maps data cited by ERR. Separating the effect of synchronisation from weather, gas prices and cable outages is not possible with annual averages, and anyone claiming a precise figure should be treated with caution.

The real cost is balancing

Inside BRELL, frequency was held largely by the Russian system. Since February 2025 the Baltic operators have had to procure their own reserves, and early on there was not enough capacity in the market. Elering said its reserve costs reached €56 million from February to July 2025 alone, and it raised its annual forecast to about €100 million. It covered the 2025 bill from congestion revenue. From January 2026 Estonian consumers and producers each pay a balancing capacity fee of €3.73 per MWh, which Elering estimates adds about €1.20 a month, VAT included, to the bill of a household using 250 kWh. The fee covers up to €60 million a year; Elering absorbs anything above that. Its chief executive, Kalle Kilk, described the fee, figuratively, as the price of energy independence.

That figure is higher than earlier estimates suggested, although the measures are not the same. In 2024 LRT reported Litgrid calculations from 2023 that synchronisation would cost an average household about €0.60 a month in Estonia, €0.50 in Lithuania and about €1 in Latvia. Those estimates covered synchronisation as a whole, not only reserves, and the Lithuanian figure assumed consumption of 140 kWh a month, so they cannot be compared directly with Elering's fee, but they point the same way: the running costs came in above the planning figures, at least in the first year.

Why the bill should shrink

The costs were concentrated early. Rolands Irklis, who chairs Latvia's AST, told LSM this week that balancing costs were a challenge until July 2025, with March and April the hardest months, and that he expects this year's payments to be two to three times lower than last year's. The main reason is new supply. The operators' own reserves, including battery systems in Lithuania and Latvia and the Kiisa plant in Estonia, reduced total balancing capacity costs eightfold between February and September 2025, according to the three operators. They plan to phase these resources out by November 2028 as commercial batteries and other providers enter the market. Total Baltic demand for balancing capacity is expected to be about 1,600 MW in 2026, so the pace at which private capacity arrives will decide how quickly consumer fees fall.

Kaliningrad on its own

The Baltic exit also left the Russian exclave of Kaliningrad without a grid link to mainland Russia. Russia's Energy Ministry said at the time that the region's power plants had a total capacity of 1.88 GW, more than twice its peak consumption, that four new plants had been built between 2016 and 2020, and that five years of annual tests had confirmed the system could run independently. Public information on how the exclave's grid has performed over the year is limited, and there have been no reports of large-scale outages in the sources reviewed here. The Kremlin spokesman, Dmitry Peskov, said at the time that Russia had taken all measures to ensure the uninterrupted and reliable operation of its unified energy system.

What to watch in year two

Reliability has held. AST's Irklis said supply reliability in Latvia had improved significantly, and the operators have received more than €100 million in EU funds, shared with Poland, for additional security solutions. The risks he named are hybrid threats, cyberattacks and sabotage. For consumers the key figure is the balancing bill. If Irklis's forecast is right and costs fall by half or more in 2026, synchronisation will look like a one-off investment with a transitional running cost. If new battery and flexible capacity is slow to arrive, the fee will remain a lasting charge on Baltic electricity bills.

Sources

• ENTSO-E — Continental European TSOs announce completion of synchronisation project with AST, Elering and Litgrid
• LSM — One year on from BRELL disconnect, Baltic states' energy grids are safer
• ERR News — Elering to add frequency balancing charge to bills from January
• ERR News — Estonia's average 2025 electricity price almost €7 per MWh lower than previous year
• ERR News — Estonia got half its 2025 electricity from Finland, though prices double
• Elering — Baltic electricity transmission operators announce plan to phase out balancing resources
• Estonian Competition Authority — Synchronisation of the Baltic States' electricity system with continental Europe
• Xinhua — Kaliningrad transitions to independent power operation as Baltic states exit Russian grid