Bulgaria’s Net Power Exports Rise 62% as Green Output and Storage Surge

Bulgaria has substantially widened its electricity trade surplus this year, with net exports reaching 3.5 TWh from January through early October — a 62 percent increase over the 2.16 TWh recorded in the same period last year. The country has been supplying neighboring Balkan states during summer heat waves and regional capacity shortfalls, according to grid operator ESO and industry association APSTE.

The widening surplus reflects uneven growth on both sides of the ledger. Total generation rose 12.24 percent, while domestic demand expanded by a smaller 8.45 percent. Renewable output reached 11.5 TWh for the period, a 34 percent year-on-year gain.

Battery energy storage posted the most dramatic shift: industrial systems discharged 1,720 GWh into the grid, up from just 190 GWh in the year-earlier period — a ninefold increase. Installed BESS capacity now approaches 6 GW with 17 GWh of total storage, alongside solar capacity of nearly 7 GW.

A single day captures how the system operates under stress. On October 8, Kozloduy’s sixth reactor was offline for maintenance and the fifth was running at reduced output because of the Danube’s diminished flow. Even so, solar plants were generating 4,300 MW against afternoon consumption of 4,100 MW, while batteries simultaneously absorbed more than 4,000 MW to build an evening reserve.

APSTE head Nikola Gazdov highlighted the seasonal imbalance that remains: solar output falls sharply in winter, and the country’s active wind capacity is only 716 MW. The association estimates that stable regulation and streamlined permitting could attract more than €4 billion in wind and storage investment by 2030.

Source: Balkan Green Energy News