The share of RES in the transmission network for the period from the beginning of the year to September 7 grows by 20.71%
Electricity production and consumption in Bulgaria remain positive. The balance (export-import) of electricity is positive. The share of baseload power plants is increasing. Renewable energy sources (RES) demonstrate a higher participation in the transmission and distribution networks, while that of hydroelectric power plants (HPP) is shrinking. Good levels are also reported in battery energy storage systems (BES)/discharge. It is important that, despite the positive data, the change compared to earlier periods is already more tangible. This is clear from the operational data prepared by the Electricity System Operator (ESO) for the period from 01.01.2025 to 07.09.2025 compared to the same period last year.
Electricity production for the period from the beginning of January to the seventh of September this year amounted to 28,029,274 MWh. This represents an increase of 8.18% (for the reporting period until August 31 or a week earlier – plus 8.69%) compared to a year earlier. For comparison, then electricity production amounted to 25,910,866 MWh.
Electricity consumption for the specified period of the current year is about 26,096,516 MWh, which is an increase of 5.48% compared to the same period last year (a week ago – plus 5.58%). According to the data, a year earlier, electricity production reached 24,740,468 MWh.
The balance (export-import) of electricity for the period from the first day of January to the seventh day of September reached 1,932,758 MWh, which is an increase of 65.14% compared to a year earlier (a week before that – plus 83.17%). During the same period last year, the balance (export-import) of electricity was in the order of 1,170,398 MWh.
The participation of base power plants remains in the plus, reaching a volume of 19,992,008 MWh for the period from the beginning of the year to September 7, which is an increase of 7.28% compared to the same period in 2024 (plus 8.18% a week ago). At that time, the share of baseload power plants amounted to 18,635,291 MWh.
Against this background, the share of renewable energy sources (RES) in the transmission and distribution networks continues to increase.
According to the system operator, the share of RES in the transmission network for the period from the beginning of January to September 7 this year reached a volume of 2,917,412 MWh or an increase of 20.71% compared to a year earlier (a week before that – plus 20.42%). According to the operator, the share of RES in the transmission network last year amounted to 2,416,790 MWh. The positive data in the reporting period of 2025 are the result of the higher participation in the transmission network of photovoltaic plants (plus 29.37%), despite the decline in wind power (minus 11.59%) and biomass (minus 19.49%).
The share of RES in the distribution network for the comparable period of the current 2025 reaches a volume of 2,956,906 MWh, which is an increase of 25.23% compared to the same period a year earlier (for the reporting period until August 31 – plus 24.93%). At that time, the participation of RES in the distribution network was in the volume of 2,361,156 MWh. The positive results for the indicated period of 2025 are due to the rather high share of photovoltaic power plants in the distribution network (plus 33.19%) and biomass (plus 6.99%), despite the decline in wind power (minus 4.89%).
The participation of hydroelectric power plants (HPPs) for the period from January 1 to September 7 this year remains in the negative, but it cannot be ignored that an improvement is again observed compared to earlier periods. According to ESO data, for the compared period this year the share of HPPs is in the volume of 2,016,547 MWh, which is a decrease compared to the previous year by 19.12% (a week ago – minus 19.38%). For comparison, a year ago, hydroelectric power plants participated in the country's energy balance with a volume of about 2,493,331 MWh.
The share of battery energy storage systems – SSEB/discharge/ during the specified period of this year is estimated at a volume of 146,401 MWh. There is no calculation in percentage terms, but the very high difference in capacities remains, as according to data last year, SSEB/discharge/ amounted to a volume of 4,297 MWh.
