Bulgaria increased electricity production by 6.84% between 1 January and 2 August 2026, while output from its traditional coal and nuclear baseload fleet declined. Data from transmission system operator ESO show national generation reached 25.95 TWh. Electricity consumption rose by 6.55% to 24.29 TWh. The resulting gap left Bulgaria with net electricity exports of approximately 1.66 TWh.
Generation totals and shift in the power mix
The change in the generation structure was led by baseload plants, defined principally as coal and nuclear facilities. These units produced 16.27 TWh, down 13.4% year on year. Total production still increased as renewable generation and other sources offset part of the baseload contraction.
Renewable electricity connected to the transmission network climbed by 13.44% to 2,773.3 GWh. Renewable output in the distribution system increased by 5.08% to 2,598.2 GWh. Combined transmission- and distribution-connected renewable generation therefore exceeded 5.37 TWh.
Nuclear support at Kozloduy and complementary generation levels
Bulgaria’s electricity balance is supported by two operating units at the Kozloduy nuclear power plant. At the beginning of August, the plant supplied close to 1,890 MW on average. Nuclear output was complemented by coal generation of around 900 MW, solar output of approximately 1,349 MW, and smaller contributions from hydro, gas and wind.
The country exported an average of 1,425 MW on 4 August, with substantial flows towards Romania and Serbia. Bulgaria supplied approximately 1,536 MW to Romania and 366 MW to Serbia, while importing electricity from Greece during parts of the day.
Cross-border flows in eastern SEE market balancing
Bulgaria’s export position supports balancing across the eastern Southeast Europe market. Romania is managing nuclear and hydrological constraints, while Serbia faces weak hydro production alongside growing summer demand. Bulgarian exports help cover both markets while supporting transfers further north towards Hungary.
The decline in baseload generation remains commercially significant for power availability over time. Higher renewable output can lift annual energy production but cannot replicate the hourly availability of coal and nuclear generation without storage, flexible demand or additional cross-border capacity . Bulgaria’s summer export strength therefore depends on continued availability at Kozloduy, the operating condition of its coal fleet, and the timing of solar production .
