In the first quarter of 2026, Slovenia experienced a significant reduction in electricity generation from its hydropower resources, prompting a shift towards thermal and nuclear generation to meet demand. Hydropower facilities along the Drava, Sava, and Soča rivers collectively produced 718 GWh, reflecting a sharp decline of 23.1% compared to the same period in the previous year. This output also fell 10.5% short of long-term projections, primarily due to weaker-than-expected hydrological conditions affecting the region.
The decrease in hydropower generation was evident across all three river basins, with the Drava and upper Sava regions experiencing the most pronounced impacts. Data indicates that river flows remained low throughout winter, compounded by limited snow reserves in the Alps which further diminished expectations for spring inflows. This situation has led to persistently constrained hydropower availability, necessitating reliance on alternative energy sources.
In response to the hydropower shortfall, other energy generation sources ramped up their outputs significantly. The Krško Nuclear Power Plant reported an impressive production of 1,516 GWh during this period, while the Šoštanj Thermal Power Plant contributed 666.3 GWh. Notably, TE-TO Ljubljana saw a remarkable surge in output to 311.9 GWh—an increase of nearly 120% year-on-year—following the commissioning of a new gas-fired unit, underscoring rapidly rising thermal flexibility within Slovenia’s energy system.
Additional contributions came from the Brestanica thermal power plant, which increased its production by approximately 53% year-on-year to reach 14.8 GWh. Despite these gains in thermal and nuclear output, the overall balancing efforts reflect a broad shift towards conventional generation methods to stabilize supply conditions, as Slovenia adapts to changing resource availability.
Total electricity supplied from domestic sources amounted to 3,226.7 GWh from January to March 2026, marking a decrease of 5.5% compared to the previous year and falling short by 1.9% against planned levels. These figures highlight the system-wide implications of reduced hydropower output on national generation balance, emphasizing ongoing challenges within Slovenia’s energy landscape.
