The Battery Energy Storage System (BESS) is one of the most important projects in the synchronisation of Baltic power grids with the continental Europe electricity system in order to ensure operational stability and the reliable supply of electricity.
Operating synchronously with continental Europe, one of the most important functions is ensuring frequency regulation and balancing reserves. In order to ensure the required frequency regulation, batteries are being installed in Latvia. An energy storage battery is equipment comprised of several energy storage batteries are intend for discharging and charging electricity within the grid, in order to ensure the required regulation of reserves upwards or downwards as needs be.
The modern battery system will ensure the necessary fast and automatically activated frequency regulation reserves for the synchronisation mode in which the Baltic States' electricity transmission system will operate synchronously with the power grids of continental Europe. Moreover, the battery system will be able to provide these reserves on more economically advantageous terms than the majority of conventional stations. These fast reserves will be crucial both while operating in synchronisation mode, and in future, as the proportion of renewable resources continues to increase within the energy system.
In 2021, after assessing potential power reserve availability and development scenarios, together with Baltic transmission system operators Litgrid AB and Elering AS, AST concluded that, from the perspective of energy supply security and economic feasibility, batteries are the best solution for providing the Baltic balancing power reserves that will be required in future. In order to provide power reserves, with Decree No.674 of 24 September 2024, the Republic of Latvia's Cabinet of Ministers gave permission for AST to acquire, install and operate battery energy storage systems for the maintenance and activation of electricity reserves.
The German company Rolls-Royce Solutions GmbH (Rolls-Royce) is installing the battery systems at the AST substations in Rēzekne and Tume with joint power of 80 MW and power of 160 MWh, which is currently one of the post powerful and biggest battery systems in the European Union. Both BESS projects in Tume and Rēzekne are due to be implemented in October 2025. Meanwhile, for the construction of BESS, both substations are being expanded, building the necessary feeder bays for the connection of BESS and installing the required transformers.
Parallel to the construction of batteries, which Rolls-Royce is performing in cooperation with the German company LEC Construction International GmbH and the Latvian company SIA Enersense, AST is developing a battery control system. This IT solution will make it possible to control batteries in accordance with a set algorithm and the situation within the grid, charging or discharging electricity within the grid.
European co-financing from CEF structural funds in the amount of 75% for BESS in Tume and substation expansion, RePowerEU 100% financing for the delivery and installation of BESS in Rēzekne.
Photo: AST Board Chairman Rolands Irklis (2nd from left) and Board Member Arnis Daugulis (centre) with Rolls-Royce Power Systems representatives Perry Kuiper, Gerbert van der Weijde and Rana Mitra
Project events
Latvia's transmission system operator AS "Augstsprieguma tīkls" (AST) has completed the construction of battery…
Latvia’s transmission system operator, JSC “Augstsprieguma tīkls” (AST), has received its first shipment from Italy.…
