Day-ahead electricity prices across Southeast Europe fell sharply for delivery on 11 June, as strong solar generation, cooler temperatures and improving regional supply conditions drove prices lower and widened the gap between renewable-rich eastern markets and premium-priced Italy. The session highlighted a growing structural divide between low-cost daytime renewable markets and higher-priced Central European hubs.
Serbia recorded the steepest decline among major exchanges, with SEEPEX falling by €37.4/MWh day-on-day to €78.37/MWh, marking the lowest price in the region. Slovenia’s BSP dropped to €94.71/MWh, while Croatia’s CROPEX settled at €96.01/MWh. Hungary’s HUPX and Romania’s OPCOM both remained close to the €100/MWh level, despite sharp declines of more than €24/MWh. Montenegro stood out on the upside at €104.74/MWh, while Italy continued to trade at a strong premium of €127.23/MWh.
The correction coincided with a noticeable cooling across Central and Southeast Europe. Average regional temperatures fell to 20.4°C, with Serbia experiencing one of the strongest drops, from 24.2°C to 18.3°C. Lower cooling demand eased system stress, while high solar availability ensured abundant daytime supply across most markets.
Total regional generation increased to around 29.1 GW, up nearly 1 GW day-on-day. Hydro output rose by 190 MW, coal by 316 MW, and gas by 317 MW, while solar remained exceptionally strong at 6.6 GW, accounting for roughly 23% of total generation. Hydropower also held a dominant position at about 24% of the mix, maintaining system flexibility despite strong renewable penetration.
As supply strengthened, regional import dependence fell sharply. Net imports dropped to just 70 MW, compared with 235 MW a day earlier, showing how domestic renewable output is increasingly displacing cross-border electricity needs during daylight hours.
Romania remained a key driver of regional renewable dynamics. Solar generation reached a new record of 2,634 MW, surpassing previous highs set only days earlier. At peak output, solar accounted for roughly 43% of Romanian generation, enabling exports of around 1,600 MW into neighbouring systems and reinforcing Romania’s role as a key renewable exporter.
This trend reflects broader structural change across Southeast Europe. Hungary has become one of the most solar-intensive power systems globally, with solar contributing around 27% of electricity generation in 2025. Rising photovoltaic penetration is increasingly reshaping price formation, suppressing midday values while amplifying evening ramp requirements.
Cross-border flows mirrored these developments. Romania and Bulgaria remained strong exporters, while Hungary, Greece, Croatia and Serbia relied on imports during parts of the day. The spread between Serbia and Italy widened to nearly €49/MWh, creating strong export incentives for generators connected to western European demand centres.
Forward markets, however, remained significantly firmer than spot prices. Hungarian Week 26 contracts traded at €117/MWh, July contracts at €121.5/MWh, while carbon allowances strengthened to €76.94/t and Austrian gas rose to €50.67/MWh. This divergence indicates that traders continue to price in weather uncertainty, hydro variability and potential summer demand spikes, despite current renewable strength.
Overall, the trading session reinforced a clear market evolution in Southeast Europe. Increasing solar penetration is now a dominant force in daytime price formation, reducing thermal influence during midday hours and reshaping dispatch patterns across Hungary, Romania, Bulgaria and Serbia. As flexibility becomes more valuable than base generation, the importance of balancing resources, storage and evening peak capacity continues to rise.
The emerging structure is increasingly defined by deep midday price compression, strong evening recovery and widening intraday spreads, creating growing arbitrage opportunities for battery operators, hydro generators and traders positioned between renewable-rich Southeast Europe and structurally tighter Western European markets.
