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, as storage becomes a core operating asset in the country’s power system. The European Bank for Reconstruction and Development (EBRD) and Raiffeisen are providing 60 million euros of debt for a new battery at the Tenevo complex.
Fleet figures and verification
Bulgaria’s reported solar capacity is 7.3 GW, implying an unusually high ratio of battery power to photovoltaic capacity. The operating fleet figures are exceptionally large for the country and require checking against underlying ESO or market data before being treated as confirmed.
Calculations cited for October 1 to 25, with no year specified, put battery supply at 18 GWh per day and absorption at 19.9 GWh per day. The figures and their time aggregation were flagged for verification against the system size.
Tenevo project and market effects
The new Tenevo battery has 246 MW of power capacity and 512.5 MWh of energy capacity, alongside a 242 MWp solar plant. The complex also has an existing battery rated at 65 MW and 260 MWh. The project expands a site that already combines merchant solar generation and battery storage.
Additional storage could absorb midday solar generation, reduce the severity of negative prices, release energy during evening peaks and provide balancing services. Greater capacity could also change 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.