Bulgaria has made significant progress in the field of battery energy storage. The country secures its electricity needs from a few very large units such as the Kozloduy Nuclear Power Plant and the Maritsa East 2 thermal power plant. Bulgaria lacks major watercourses (with the exception of the Danube) and does not have very large hydropower plants; therefore, energy storage represents a challenge. Bulgaria has over 5 GWh of battery storage, as well as a chain of pumped-storage hydropower plants such as Belmeken–Sestrimo–Chaira, with a capacity of 864 MW.
The 202 MW stand-alone BESS plant developed by ContourGlobal—one of the largest battery energy storage projects in Bulgaria and Eastern Europe, with a total storage capacity of 500 MWh—has recently commenced operations. The facility is actively participating in both the national day-ahead and intraday electricity markets, supporting optimized power dispatch, improved balancing between electricity generation and consumption, and the integration of renewable energy sources, while also contributing to increased overall stability and flexibility of the power system.
The advanced technical features of the BESS facility enable it to provide advanced grid services. It is equipped with the latest battery technology, including 110 battery skids supplied by BYD and 28 combined Power Conversion System (PCS) and transformer units, which convert the direct current (DC) from the batteries into alternating current (AC) for the grid. This is BYD’s largest project in Eastern Europe to date.
The new BESS facility in the country also stands out for its exceptional execution schedule, moving from the Final Investment Decision (FID) to Commercial Operation Date (COD) in less than nine months, with construction and commissioning completed in just seven months and full installation achieved in October 2025.
