Greenvolt Power, part of the Greenvolt Group and a leading developer of large-scale renewable energy projects, has officially inaugurated the Turośń Kościelna battery energy storage facility, one of the largest systems of its kind in Poland. Located in the Podlasie Voivodeship, near Białystok, the facility has a grid connection capacity of 200 MW and a storage capacity of 800 MWh, being connected to the national electricity transmission grid at a voltage of 110 kV.
The facility can take and store electricity from the grid when it is available in larger quantities, in order to deliver it back during peak periods. Thus, it contributes to balancing the Polish National Electricity System, providing system services and capitalizing on electricity produced from weather-dependent renewable sources. Starting in 2028, the project will also be included in the Polish capacity mechanism, under a 17-year contract, providing the system with 170 MW of capacity, equivalent to 85% of the plant’s nominal power.
More flexibility for Poland’s national electricity system
As the installed capacity of solar and wind projects increases, so does the need for solutions that allow energy to be stored and used at the right time, as well as quickly adapting to variations in production and consumption in the grid. The Turośń Kościelna facility can adjust its operation mode according to the needs of the system, thus contributing to increasing its flexibility and reducing the risk that available energy from renewable sources cannot be taken into the grid.
The project reflects a broader transformation taking place in the Polish energy market, where energy storage is becoming one of the fastest growing segments of the capacity mechanism. In the main tender, for the delivery year 2028, 33 electrochemical energy storage plants were awarded contracts, with a cumulative capacity obligation of over 1.7 GW. According to the Polish Energy Regulatory Authority, energy storage plants accounted for a total of 15% of the contracted capacity.
“As energy systems become more electrified and rely more and more on renewables, flexibility is becoming an indispensable element of the energy transition. Poland is one of the markets where large-scale energy storage systems play a particularly important role, and the investment in Turośń Kościelna strengthens Greenvolt’s position in one of the fastest growing segments of the energy sector. Battery energy storage is one of our main growth drivers. We are actively developing projects in 13 countries and have a battery storage project portfolio with a total capacity of 5 GW in the pipeline, and achievements such as this reflect the breadth of our commitment to this technology,” said João Manso Neto, CEO of Greenvolt Group.
196 battery modules and 49 transformer stations
The facility consists of 196 containerized battery modules and 49 containerized transformer stations. It uses lithium iron phosphate (LFP) technology and can respond to signals from the system operator in just a few seconds, much faster than conventional power plants. The high durability of the cells, together with the efficiency of the charging and discharging processes, contribute to an estimated operating life of over 20 years.
The ancillary infrastructure includes monitoring and protection systems, fire safety solutions and acoustic barriers designed to limit the impact of the facility on surrounding areas. The project site covers an area of approximately 35,000 square meters. Over 25,000 square meters, representing more than 70% of the total area, are preserved as biologically active surface. The project has undergone a social and environmental assessment, in accordance with the standards of the International Finance Corporation (IFC), a member of the World Bank Group, and the European Bank for Reconstruction and Development (EBRD).
Both institutions’ standards cover the assessment of a project’s impact on the environment and local communities, as well as measures to mitigate the identified risks.
P&Q was the general contractor for the project, and BYD Energy Storage provided the battery storage technology used by the facility.
Greenvolt Power expands its portfolio of energy storage projects
Greenvolt Power is also nearing completion of a similar project in Ełk, located in the Warmian-Masurian Voivodeship, which has the same nominal power and storage capacity as the Turośń Kościelna facility, namely 200 MW and 800 MWh. The start of commercial operation is scheduled for the fourth quarter of 2026. Together, the two facilities will provide a total power of 400 MW and a storage capacity of 1.6 GWh. The company is also developing the Siedlce project, which will have a power of 600 MW and a storage capacity of 2.4 GWh, which will become the largest BESS project in Poland and one of the largest in Europe.
This important milestone follows the inauguration last month of the Buj battery energy storage system in Hungary, the largest system of its kind currently in operation in the country, with a power output of 99.8 MW and a storage capacity of 288.6 MWh. Together, the Buj and Turośń Kościelna projects highlight the growing scale and geographical expansion of Greenvolt Power’s energy storage activities in some of the most dynamic European markets for large-scale storage projects.
“The Turośń Kościelna project is particularly important for us, as it demonstrates that large-scale energy storage is becoming a concrete component of the Polish power system. Today we are officially presenting a completed and grid-connected 110 kV facility, while we are approaching the completion of a second project of the same size in Ełk and developing the Siedlce project with a planned capacity of 600 MW and a storage capacity of 2.4 GWh. In this way, we are constantly expanding the scope of Greenvolt Power’s activities in the field of BESS systems in Poland,” said Weronika Nowak, CEO of Greenvolt Power. Greenvolt Power has a diversified portfolio of 12.8 GW, which includes onshore wind, solar and battery energy storage projects. Battery energy storage remains one of the company’s main growth drivers, accounting for 5 GW of the total portfolio of projects under development. In Poland, at the end of June 2026, Greenvolt Power’s portfolio included energy storage projects with a capacity of 2,595 MW, solar photovoltaic projects of 657 MW and wind projects of 238 MW. Greenvolt estimates that it will invest approximately EUR 800 million in renewable energy assets in Poland by the end of 2026, reinforcing its long-term commitment to accelerating the country’s energy transition and strengthening energy security.
