A 582MWh battery storage project and a gigawatt-hour-scale thermal energy storage system are the latest big developments in the emerging Baltic region, north-eastern Europe.
The Baltic States of Estonia, Lithuania and Latvia uncoupled their electricity grids from the BRELL network formerly shared with Russia and Belarus last year. Energy storage has been seen as a key strategic enabler for synchronisation and harmonisation with Europe’s transmission network, along with goals such as increasing the adoption of renewable energy.
Utilitas brings online 1,100MWh TES system for district heating network
So far, much of the excitement has been justifiably focused on opportunities for battery energy storage systems (BESS), with ancillary services prices in the Baltics currently “through the roof,” according to some commentators.
In Estonia earlier this month, however, the Baltic region’s largest thermal energy storage (TES) system was inaugurated by renewable energy producer and district heating and cooling network provider Utilitas.
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Väo thermal storage facility is a large-scale heat accumulator, built at an energy complex in the Estonian capital Tallinn. The second of four such facilities planned for construction by the heating utility in Estonia this year, the TES facility has been built with 80MW output and 1,100MWh energy storage capacity.
“The established thermal storage unit allows heat to be stored and used when heat consumption is high, thereby helping to strengthen the reliability of the district heating network,” Mayor of Tallinn Peeter Raudsepp said.
“Greater flexibility and a more stable district heating network are in the interests of every resident of Tallinn.”
It stores 20,000 cubic metres of water in tanks 42 metres high and 26 metres in diameter and was built for Utilitas by industrial services company Bilfinger’s subsidiary Granitor Rodoverken. Power to ‘charge’ the 1,1GWh system with heat comes from two high-efficiency combined heat and power (CHP) plants and two solar PV plants at the Väo energy complex.
Utilitas CEO Priit Koit said the storage facility enables better response to variability in energy consumption, increases production efficiency and enhances the security of energy supply.
Co-financed by Estonia’s Environmental Investment Centre and supported with €675,000 (US$801,300) through the European Union (EU) NextGenerationEU economic recovery mechanism, the project’s total cost was around €8 million.
“Investments must be continued, and the thermal storage facility that has been built is an example of how investments made in the interests of consumers and to increase security of supply are also economically expedient,” said Tallinn mayor Raudsepp.
The scope and scale of the heat storage facility are similar to other projects invested in elsewhere in northern Europe, perhaps most notably large-scale TES plants for district heating purposes built in Finland using a ‘Sand Battery’ technology from startup Polar Night Energy.
Market experts and trade associations, including Energy Storage Europe, have tipped thermal energy storage as a technology to watch closely, given its strong role in decarbonising heating, particularly in industry, alongside parts of northern Europe with residential district heating networks.
Read more Energy-Storage.news coverage of thermal energy storage (TES).
Nidec Conversion partners Rolls-Royce on state-owned Lithuania BESS portfolio
The Utilitas project’s inauguration comes shortly after the official opening of Estonia’s largest BESS plant, Hertz 1, through joint venture (JV) developer Baltic Storage Platform (BSP) earlier in the month.
All three Baltic States are seeing a rise in BESS investment. In Lithuania, state-owned energy holding company Ignitis Group is building a three-site portfolio of battery storage systems totalling 291MW/582MWh.
The company took a final investment decision (FID) on the trio in July last year, revealing that the portfolio, scheduled to start commercial operations in 2027, would require a total investment of around €130 million.
That includes funding via EU state aid, with the Ministry of Energy of Lithuania aiming to enable the deployment of 1.5GW/3.2GWh of energy storage through capex funding support capped at 30% of eligible costs and a maximum funding per megawatt-hour of €100,000.
Ignitis Group has already ordered BESS equipment for the projects from the system integrator arm of Rolls-Royce. Rolls-Royce Power Systems will supply its mte EnergyPack BESS solution for the projects: two close to wind power plants in northwest Lithuanian cities (Kelmė, 147MW/294MWh and Mažeikiai, 45MW/90MWh) and one in central Lithuania close to a pumped hydro energy storage plant (Kruonis, 99MW/198MWh).
Yesterday, power electronics, energy storage system (ESS) and engineering firm Nidec Conversion said it is partnering with Rolls-Royce and providing a combined power conversion system (PCS), transformer and medium-voltage (MV) switchgear solution for the three sites.
Nidec Conversion’s Power Unit is, the company claims, a compact, high-power-density, low-noise, integrated skid-mounted solution.
Energy-Storage.news publisher Solar Media is hosting the Energy Storage Summit EU 2026 in London, UK, on 24-25 February 2026 at the InterContinental London – The O2. See the official website for more details, including agenda and speaker lists. Plus, ESN Premium users can get a 30% discount on tickets.
