ContourGlobal has commissioned a 202 MW/500 MWh standalone battery energy storage system (BESS) in the Stara Zagora region of Bulgaria. The facility is fully operational and is participating in the country’s day-ahead and intraday electricity markets. Located on a 25,000 square metre site within the Maritsa East 3 coal-fired power plant complex, the project is funded through the European Union’s NextGeneration EU programme under Bulgaria’s National Recovery and Resilience Plan.
The project supports power system balancing, flexible dispatch, and integration of renewable energy, while contributing to grid stability and reliability. The remaining operational coal units at Maritsa East 3 continue to supply electricity during peak demand periods, supporting national energy security alongside the new storage facility. Construction and commissioning of the project were completed in seven months, with the project reaching commercial operation in less than nine months from final investment decision.
The plant incorporates advanced battery technology, including 110 battery skids supplied by BYD and 28 combined power conversion system and transformer units that convert direct current to alternating current for grid injection. Additionally, ContourGlobal is developing a second 202 MW BESS project at the same site as part of a broader plan to establish an integrated renewable energy hub.