Bulgaria’s electricity sector has achieved a significant milestone in 2025, with renewable energy sources becoming the country’s second-largest electricity producer, trailing only nuclear power. For the first time, the combined output from solar, wind, hydropower, biomass, and waste has outstripped that of coal-fired plants, indicating a substantial shift in the energy landscape.
The Electricity System Operator (ESO) attributes this transition largely to the rapid growth of solar power capacity and advancements in battery storage technology. These developments have allowed for extended operational hours of photovoltaic systems. In contrast, coal generation has continued to decline, reaching its lowest recorded levels in Bulgaria.
As a net exporter of electricity, Bulgaria’s exports totaled 1,268 GWh—significantly lower than the strong export levels seen in 2022. This decrease highlights a changing role within the regional market. Since 2023, coal generation has decreased sharply, with output in 2025 approximately 60% lower than in 2022. This reduction exceeds the targets set under the Recovery and Resilience Plan, which aimed for a 40% decrease compared to 2019 levels; actual reductions now stand at nearly 49%.
Looking ahead to 2026, pressure on coal plants is anticipated to increase as the contract for AES Galabovo, a US-owned facility, expires. High carbon allowance prices around €85 per ton have diminished the competitiveness of coal-fired generation. Consequently, state-owned TPP Maritsa East 2 is shifting towards supplying regulated household consumption via a new exchange-based purchasing model while operating at a loss. Despite these challenges, coal is expected to remain Bulgaria’s third-largest source of electricity for several years due to limited natural gas utilization in power production.
Solar energy is experiencing rapid growth; approximately two-thirds of Bulgaria’s installed solar capacity—over 4.5 GW—was added within the last three years. Enhanced panel efficiency and battery systems have resulted in a fourfold increase in solar output since 2022. By 2025, solar power alone was generating around two-thirds of what coal-fired plants produced and could surpass 80% of coal generation as early as 2026. This year also anticipates record installations of battery storage systems that will help manage solar energy production and stabilize pricing fluctuations throughout the day.
However, wind energy development faces significant delays due to prolonged administrative and environmental approval processes that can take three to five years. This is particularly critical as wind generation typically peaks during nighttime and winter months when solar output is low. New wind farms with capacities between 70–100 MW are not expected to commence operations until late 2027.
Bulgaria’s role within the regional energy market is evolving; rather than primarily acting as an exporter, it increasingly serves as a balancing hub. Data from ENTSO-E indicates that Bulgaria has become a consistent net importer from Greece and Turkey—countries that have advanced more rapidly in their energy transitions by expanding renewables and replacing much of their coal generation with gas.
In the future, Bulgaria may position itself as a crucial flexibility provider within southeastern Europe. With ongoing expansions in battery storage capacity and plans for new pump-storage hydropower projects, Bulgaria holds potential as a large-scale energy buffer capable of delivering both commercial benefits and strategic advantages amid an evolving regional energy landscape.
