Greenvolt and BYD to build Poland’s largest battery storage plant in Siedlce

Greenvolt Power, part of the Greenvolt Group, has signed a contract with BYD Energy Storage to supply its BYD Haohan battery system for the Siedlce Battery Energy Storage System (BESS) in Poland. The project will have a capacity of 600 MW and store 2.4 GWh, making it the biggest battery storage facility in the country and one of the largest in Europe.

Construction is scheduled to begin in the third quarter of 2026, with commercial operation targeted for the end of 2027. Revenue for the plant is already secured through Poland’s capacity‑market mechanism. Once operational, the storage unit is expected to enhance grid stability, increase flexibility, and aid the integration of growing renewable energy generation in Poland and Central‑Eastern Europe.

CEO João Manso Neto of Greenvolt Group highlighted the project as a “key milestone” in the EU’s energy transition, while BYD Energy Storage’s General Manager Yin Xueqin emphasized the trust placed in their technology for a project of this scale.