South-east European day-ahead electricity markets opened September with Serbia showing a sharp price recovery and a tightly grouped Hungary-Romania-Bulgaria-Greece set of levels. The move coincided with stronger weekday demand, higher regional imports and sensitivity to the evening ramp. The market pricing also continued to reflect cross-border flow patterns between central Europe and the Balkans.
In the Hungary market, the HUPX base price settled at €176.74/MWh, up €3.3/MWh day on day. Romania was slightly higher at €177.28/MWh, while Bulgaria and Greece were close at €174.59/MWh and €174.68/MWh respectively. Albania traded at €174.42/MWh.
Serbia recorded the largest shift, with SEEPEX rising by €34/MWh to €166.25/MWh after Monday’s level of €132/MWh. Croatia settled at €170.05/MWh, Slovenia at €168.53/MWh, Montenegro at €158.50/MWh and North Macedonia at €148.46/MWh. Italy remained the premium market at €198.82/MWh, about €22.08/MWh above HUPX, while Germany traded at €143.80/MWh.
Price layers and cross-border flow incentives
The regional price map showed three layers, with Romania, Hungary, Bulgaria, Greece and Albania clustered around €174-177/MWh. Croatia and Serbia sat roughly €7-11/MWh below Hungary, while Montenegro and North Macedonia were discounted further. Germany remained significantly cheaper than the eastern cluster, while Italy was materially more expensive than all other referenced markets.
This structure supported a north-to-south and west-to-east transit pattern through central Europe and the Balkans. The balance change most directly tied to the pricing was demand, with regional consumption forecast at 33.27 GW, up about 2.40 GW day on day. Net imports increased by 614 MW to 2.87 GW, while inflows from the Austria-Slovakia direction rose by 708 MW to 3.58 GW.
Renewables output improved but did not fully offset the demand increase, according to forecasts for solar and wind generation. Solar was expected to rise by about 1.53 GW to 7.38 GW, while wind increased by roughly 369 MW to 1.46 GW. Incremental solar and wind covered most of the consumption rise but not all of it.
The region also continued exporting into Italy while importing from central Europe, with flows towards Italy around 1.10 GW, up from 1.03 GW the previous day . This combination left the system importing heavily through Austria and Slovakia while drawing volumes out of Slovenia, Montenegro and other western Balkan routes due to the Italian premium.
German-Hungarian spread narrows; Italy keeps exports above 1 GW
The German-Hungarian spread narrowed sharply as HUPX’s premium to Germany fell to €32.94/MWh from about €61.6/MWh a day earlier . The change followed a stronger rebound in the German day-ahead market relative to Hungary’s base price move.
Despite that narrowing, core imports into the SEE-Hungary area increased to 3.58 GW, indicating that demand recovery outweighed the reduced price differential for marginal power movements eastwards . Italy’s pricing provided a counter signal: its base price of almost €199/MWh maintained enough premium to keep SEE-to-Italy exports above 1 GW.
Evening re-pricing dominates hourly curves
The hourly curves showed wider intraday movement than daily averages for multiple markets . At HUPX, prices fell to around €80/MWh during hour 11 before rising to a maximum of €276.50/MWh at hour 20. Romania followed a similar profile, with its peak reaching about €283/MWh around hour 20.
Bulgaria, Greece, Croatia and Slovenia displayed a comparable shape, with a daytime trough followed by steep evening re-pricing as solar output declined . The charts indicated Hungarian, Romanian, Bulgarian and Greek curves moving almost synchronously through the evening ramp, while Germany stayed materially below eastern markets for much of the day.
This pattern kept an intraday challenge in place: additional solar reduced prices during daylight hours but did less after sunset when scarcity conditions tightened . As a result, traders focused on spreads between midday and evening values alongside national market differentials.
Serbia tightens; Romania nuclear output remains absent
Serbia showed a clear weekday reset in its balance as consumption rose to 3.87 GW from 3.57 GW . Domestic generation increased to 3.34 GW from 3.14 GW, leaving only part of the roughly 291 MW demand rise covered by generation growth . Serbian net imports rose to 521 MW from 434 MW.
On base-load average commercial schedules, Serbia received around 247 MW from Hungary, 218 MW from Bosnia and Herzegovina, 141 MW from Bulgaria and 136 MW from Croatia . Serbia exported about 120 MW to Montenegro and around 105 MW towards Romania . The tightening coincided with SEEPEX increasing by €34/MWh to around €166/MWh.
The Serbian market still traded about €10.5/MWh below HUPX, so prices moved higher without fully converging with Hungary . Serbia’s curve also showed an evening spike reaching around €253/MWh, consistent with tighter peak-hour conditions rather than only a higher flat baseload level .
Romania remained the key structural risk for eastern SEE balancing as its day-ahead price was €177.28/MWh, highest within the coupled Hungary-Romania-Bulgaria-Greece group . Romanian consumption was around 5.81 GW, compared with generation of only 4.79 GW, producing net imports of approximately 1.03 GW. The daily balance showed zero nuclear production.
The nuclear shortfall aligned with continuing loss of Cernavoda output as Romanian authorities extended emergency energy measures through September due to low Danube levels constraining the plant . Romania was receiving about 746 MW from Hungary and 314 MW from Bulgaria on a base-load flow basis while maintaining smaller exports towards Moldova .
Bulgaria exports; Hungary acts as transit hub; Montenegro remains discounted
Bulgaria provided part of that buffer with generation of about 4.97 GW against consumption of 4.02 GW, leaving net exports close to 954 MW. Base-load commercial schedules included approximately 314 MW towards Romania, 141 MW towards Serbia, 124 MW towards North Macedonia and 475 MW towards Greece . This helped explain why Bulgarian and Greek prices stayed almost exactly aligned despite substantial bilateral flows.
