Southeast European day-ahead electricity markets sharply diverged for delivery on Sept. 29, with prices rebounding across Hungary, Romania, Bulgaria and the northern Balkans while Serbia, Greece, Montenegro and North Macedonia remained at deep discounts, highlighting increasingly constrained north-south and east-west trading corridors.
Hungary’s HUPX base price rose €8.9/MWh to €170.11/MWh, while Romania climbed €15.6 to €169.92/MWh and Bulgaria gained €15.7 to €161.82/MWh. Croatia reached €172.76/MWh and Slovenia €174.01/MWh. By contrast, Serbia’s SEEPEX slipped to just €110.06/MWh, Greece fell to €121.97/MWh, Montenegro to €130.96/MWh and North Macedonia to €132.21/MWh.
The result was an unusually fragmented regional market. Serbia traded almost €60/MWh below Hungary, Greece was €48/MWh below HUPX, while Montenegro and North Macedonia were around €38-39/MWh cheaper. Albania, at €147.58/MWh, remained about €23 below Hungary. At the other end of the market, Italy averaged about €203/MWh, almost €93 above Serbia and €81 above Greece.
The strongest shift occurred between Hungary and Germany. German day-ahead prices fell to around €165.83/MWh, leaving Hungary about €4.3/MWh above Germany. Only a day earlier Hungary had traded roughly €34/MWh below Germany, representing a swing of nearly €39/MWh in the bilateral spread. Austria stood at €180.55/MWh, while Italy remained the region’s highest-priced major market at about €203/MWh.
That reversal coincided with a major change in the regional physical balance. Combined Hungary and SEE consumption increased to 29,105 MW, up around 740 MW day on day, while the region shifted from a net export position of 1,288 MW on Sept. 28 to net imports of 555 MW on Sept. 29 — a swing of more than 1.8 GW. Imports from the Austria-Slovakia/core direction reached about 1,367 MW, reversing the previous day’s 501 MW flow in the opposite direction.
The change helps explain the rebound in HUPX and nearby markets, but not the entire regional price structure. Hungary remained a net importer of roughly 1,007 MW, compared with 731 MW a day earlier, while its domestic consumption increased to 4,516 MW against generation of around 3,509 MW. Commercial flows showed particularly strong imports from Slovakia and Romania, while Hungary continued exporting towards Croatia and Slovenia.
Romania remained a net exporter, but its surplus dropped sharply to about 187 MW from 866 MW on Monday. Bulgaria’s exports also fell to 571 MW from 1,212 MW. These reductions tightened the northern and eastern SEE balance just as regional demand recovered from the lower weekend levels.
The southern markets told a different story.
Greece fell €13.1/MWh to €121.97/MWh, despite exporting more than 1 GW on average. Its hourly profile showed one of the clearest examples of renewable-driven price compression: the Greek peak-period average was only €55.7/MWh, compared with an off-peak average of €188.2/MWh, while the minimum hourly price reached zero. The shape points to very strong daytime renewable availability followed by a steep evening recovery.
Serbia was even cheaper on a baseload basis. SEEPEX averaged €110.1/MWh, with peak power at only €103.1/MWh and a daily minimum of €9.8/MWh. The maximum nevertheless reached €240.1/MWh, showing that the market remained highly volatile despite the low daily average. Montenegro fell by more than €34/MWh to €131/MWh, while North Macedonia dropped by about €18/MWh to €132.2/MWh.
The different timing of the low-price hours is important. Greece’s deepest price compression occurred during the solar-heavy daytime period, while Serbia’s minimum was recorded in the early hours. That suggests the Balkan discount was not driven by a single renewable factor but by a combination of local supply, hourly demand, cross-border capacity and transmission constraints.
Italy continued to provide the main high-price outlet for surplus SEE electricity. Regional exports towards Italy averaged about 1,245 MW, while Italy traded around €203/MWh. Montenegro’s interconnector flows illustrate the commercial pull: the country exported about 532 MW towards Italy on a baseload basis even while its overall system remained a small net importer, effectively drawing electricity from neighboring Balkan systems and sending power west through the submarine link.
Forward markets also pointed to continued firmness in Hungary. Hungarian Week 41 power rose to around €202/MWh, Week 42 to €205/MWh and October to €204.50/MWh. However, forward Hungary-Germany premiums narrowed, suggesting traders still see some scope for stronger central European supply relative to SEE. Gas remained expensive, with CEGH around €74.75/MWh, while EUA carbon allowances stood near €86.17/t.
The Sept. 29 session therefore showed less a uniformly tightening SEE market than a fragmented system in which transmission capacity increasingly determines value. Hungary and Romania responded to the shift back towards regional imports, Italy maintained a strong pull on Balkan electricity, yet Serbia and Greece remained isolated in much cheaper hourly structures.
For traders, the key signal is the spread rather than the regional average: a market stretching from roughly €110/MWh in Serbia to €203/MWh in Italy is offering substantial cross-border value, but the persistence of those gaps shows how much of that value remains trapped behind congestion and limited transfer capacity.
