BYD to supply battery systems for Greenvolt’s 600 MW / 2.4 GWh Polish project

Greenvolt Power, the Greenvolt Group's utility-scale renewable-energy platform, has begun construction of the Siedlce battery energy storage system in Poland. Rated at 600 MW / 2.4 GWh, it is expected to become Poland's largest battery-storage installation and one of Europe's leading large-scale projects when completed. Commercial operation is planned by the end of 2027.

The project extends BYD Energy Storage's partnership with Greenvolt Power following supply agreements signed in March 2025 for Turosn Koscielna and Nowa Wies Elcka, each rated at 200 MW / 800 MWh. Their combined storage cooperation in Poland therefore reaches 4 GWh.

BYD will supply the complete battery system. The design includes 210 battery containers and 105 transformer containers equipped with power conversion systems, providing bidirectional energy exchange between the batteries and the grid.

The project will use BYD's Haohan storage system, which the report describes as incorporating the world's largest dedicated storage blade cell, rated at 2,710 Ah. The smallest system unit is stated as 14.5 MWh, with energy density equivalent to 10 MWh in a 20-foot container. The system is intended to reduce the number of containers, site footprint and associated land and construction costs, an important consideration as suitable land becomes more constrained in Poland.

Engineering and construction companies P&Q and ONDE will deliver the project together. P&Q is responsible for connecting the storage system to the 400 kV network operated by Poland's transmission system operator PSE. ONDE will build the substation and undertake civil and electrical works. The report presents the division of responsibilities as an example of Chinese storage technology being combined with local European engineering capabilities.

The project has secured long-term revenue through Poland's capacity-market mechanism, supporting the financial basis for investment. Storage facilities can obtain fixed income by participating in capacity auctions, reducing investment risk. The report identifies this market framework as one of the factors attracting international capital to Polish storage.

Siedlce is an important part of Greenvolt's storage strategy. The company has a probability-weighted BESS pipeline of approximately 4.6 GW, including about 2.4 GW in Poland. Its 200 MW / 800 MWh Turosn Koscielna project entered operation in July 2026, while the 200 MW / 800 MWh Elk project is scheduled to begin commercial operation in the fourth quarter of 2026. With all three installations in service, the portfolio would provide 1 GW / 4 GWh. Greenvolt Group chief executive João Manso Neto described Poland as an important market where battery storage is increasingly a central engine of business growth.

The development comes as Europe accelerates storage deployment. In June 2026, 22 EU member states committed to adding 45 GW of storage by 2028 to improve grid flexibility and renewable integration. Poland's rapid growth in renewable capacity is increasing demand for flexible resources and large battery installations. Siedlce is expected to strengthen peak and frequency regulation while providing another large-scale European application for Chinese storage suppliers.

For BYD, continued progress in Poland strengthens its position in Europe's utility-storage market. Alongside its previously signed 11.275 GWh order with Masdar in the Middle East, the projects illustrate a model combining battery-system supply with local engineering. The company is extending its international business from equipment exports toward coordinated system delivery and deeper local participation.