IENE reported that Bulgaria’s operating battery fleet had reached 6.23 GW of power and more than 19 GWh of energy by late October. The reported scale puts storage at the centre of Bulgaria’s power system, rather than at the pilot stage.
Bulgaria’s solar capacity was reported at 7.3 GW, implying an unusually high ratio of battery power to photovoltaic capacity. Calculations for October 1 to 25 put battery supply at 18 GWh per day and absorption at 19.9 GWh per day; the year was not specified, and both the figures and their time aggregation need checking against the system size.
Tenevo project adds storage
The European Bank for Reconstruction and Development (EBRD) and Raiffeisen are providing €60 million of debt for a new battery at Bulgaria’s Tenevo complex. The project has a power capacity of 246 MW and an energy capacity of 512.5 MWh, and sits next to a 242 MWp solar plant.
Tenevo already has a 65 MW / 260 MWh battery, alongside the solar generation. The new project adds scale to a site that combines merchant solar generation and battery storage.
Market effects and data checks
More storage in Bulgaria could absorb midday solar generation, reduce the severity of negative prices, release energy during evening peaks and provide balancing services. Greater capacity could also alter cross-border power flows into Romania, Greece, Serbia and North Macedonia.
As storage penetration rises, arbitrage spreads are expected to compress, pushing developers toward more sophisticated revenue stacking. The reported fleet totals are exceptionally large for Bulgaria and should be checked against underlying ESO or market data before being treated as confirmed.
