Power prices, trading conditions and cross-border constraints
Trading activity in Southeast Europe was shaped by wind variability and grid limitations during the week of September 14 to September 20, 2026. Hungary’s premium widened as weaker wind lifted SEE imports and spot prices on September 18. Grid constraints split regional power markets on September 17, with Serbian pricing falling while Hungary’s moved higher. CBAM-related changes also featured in market coverage, including a reduction in Western Balkan electricity trade with the EU on September 16.
Market reporting also highlighted scarcity dynamics despite demand shifts. SEE power prices retreated on September 15, but evening scarcity kept market risk elevated. A trading note dated September 16 pointed to a solar-driven correction in SEE power prices as Italy decoupled. Separate reporting on September 17 said reduced cross-border trading tightened Southeast European power markets.
Nuclear, hydropower and system availability
Nuclear generation updates included operational and planning developments across the region. Slovenia’s Krsko output fell 8.4% below its August plan on September 17. Romania’s Cernavodă shutdown removed 1.4 GW from the electricity system on September 16. Bulgaria also faced generation adjustments tied to river conditions, with low Danube levels forcing another cut at Kozloduy unit 5 on September 15.
Hydropower availability was also a focus in the period. Montenegro restored the Perucica hydropower plant to full 307 MW on September 17. Bosnia and Herzegovina reported that Visegrad hydropower output rose in August on September 15.
Renewables build-out: batteries, solar projects and wind expansion
Battery and hybridisation projects were among the most prominent renewables themes. Serbia’s 2 GW battery pipeline moved into grid contracts as power arbitrage changed on September 20. PPC advanced a 129 MWh Romanian wind battery as hybridisation spread to operating assets on September 20. In Greece, AKTOR moved for 51% of a €370 million DEPA hybrid portfolio as Greek storage consolidated on September 20.
Solar developments spanned multiple countries and included both new capacity and storage additions. Nofar brought 315 MW of Romanian solar capacity online on September 17, while OMV Petrom added a 20 MW battery to its Ișalnița solar project on September 14. Hungary’s MOL turned its Algyő oil-and-gas site into a hybrid energy hub with solar and battery storage on September 20, and E.ON added Hungarian batteries to manage solar growth and evening peaks on September 17.
Wind expansion was reported alongside permitting and financing updates. Čibuk 2 expanded Serbia’s largest wind power complex to 312 MW on September 16, while Serbia’s Vranje approved a planning framework for a 100-MW Poljanica wind farm on September 15. Bosnia and Herzegovina lines up funding for wind and grid rebuild with €103 million reported for diversification efforts on September 20, and DRI refinanced a €50.6 million facility for Romania’s Ruginoasa wind farm on September 14.
Electricity demand, price signals and winter preparation
Demand and price movements were tracked across several markets as winter risk approached forward curves. Romanian household power demand fell 11.9%, linked to shifts in the generation mix, according to reporting dated September 16. On the same date, Romanian power prices retreated from €238, while flexibility shortages remained in place. Romanian January power cleared above €205/MWh as winter risk moved into forwards on September 20.
Serbia’s winter preparations were described as being under pressure from oil, gas and weak hydrology on September 16. Reporting also covered Bosnia and Herzegovina’s regulator ERS ruling out a power-price increase while betting on new renewable capacity on September 14. Montenegro’s electricity system planning included grid connections for 3 GW, with renewable bottlenecks shifting toward networks on September 20.
Nuclear policy review, gas supply strategy and fuel support measures
Nuclear policy coverage included Hungary putting Paks II under year-end review as solar growth reshaped nuclear economics on September 20. Slovenia’s hydrogen plans were also noted as a controllable link between power and gas grids on September 16, alongside reporting that Montenegro laid groundwork for a two-tier flexibility market the same day.
The gas segment focused on supply routes and LNG positioning in the region. Hungary targeted an exit from Russian gas by October 2027, with southern supply routes gaining strategic value on September 20. Albania positioned a proposed LNG terminal as a Southeast European supply hub on September 14.
Oil-related measures included Bulgaria deploying a €300 million fuel-shock package as diesel costs hit industry on September 20. Bosnia and Herzegovina’s Republika Srpska extended a fuel subsidy as oil costs pressured the budget on September 17.
LNG corridors, grid links and regulatory developments
The period also included cross-regional energy corridor discussions involving multiple countries around green electricity trade routes. Turkey, Azerbaijan, Georgia and Bulgaria targeted a November deal on a green power corridor dated September 14. The Greece-Egypt GREGY power link advanced technical studies and financing talks on that same date.
[CBAM]-related policy changes were repeatedly referenced across market coverage during the week. CBAM redirected Western Balkan electricity trade towards Serbia and Ukraine on September 18, while revised CBAM rules could reopen EU markets to Balkan renewable electricity that same day. EU Parliament backing for CBAM electricity changes was reported for September 18 as well.
Civil infrastructure upgrades: refineries, transport disputes and storage projects
Croatia’s INA completed a €15 million efficiency upgrade at its Rijeka refinery on September 14, while Romania’s OMV Petrom completed a €115 million Petrobrazi power upgrade on September 15 . In Bosnia and Herzegovina, Energoinvest took a gas transport fee dispute to the RS Supreme Court dated September 14 . North Macedonia lined up €119 million for storage and grid upgrades as flexibility replaced coal capacity on September 20.
The week also included additional renewables permitting milestones in Slovenia and Montenegro. HSE secured a permit for a solar and battery project at a former Slovenian landfill on September 14 , while Montenegro’s EPCG unit advanced its 40-MW Kapino Polje solar project on September 15 . Montenegro also opened talks with Japan covering grids, LNG and energy technology during that same date window .
