South-east European day-ahead electricity prices rose sharply for delivery on Friday, 21 August, with Serbia recording the strongest increase in the region. Firmer German and Central European markets, together with tighter supply conditions in Hungary, pushed much of central Southeast Europe toward the €170-175/MWh range.
The regional increase was broad but uneven. HUPX rose by €12.7/MWh to €174.06/MWh, while SEEPEX Serbia surged by €35.8/MWh to €167.74/MWh, about a 27% gain in a single session. Bulgaria increased by €15.3/MWh to €169.08/MWh, Greece by €16.2/MWh to €162.73/MWh, Croatia by €12.5/MWh to €173.82/MWh and Slovenia by €11.3/MWh to €173.18/MWh.
Germany recorded an even stronger increase than Hungary, climbing €21.3/MWh to €169.56/MWh. This narrowed the Hungarian premium over Germany to just €4.50/MWh, compared with around €13/MWh a day earlier. Austria, Croatia and Slovenia also converged closely with HUPX, forming a tightly priced Central European-Adriatic block.
Price levels diverge between central Europe and southern Balkans
Further south, prices remained significantly lower than in central Europe. Albania settled at €160.54/MWh, Montenegro at €153.93/MWh and North Macedonia at €140.58/MWh. North Macedonia traded almost €33.5/MWh below Hungary and more than €40/MWh below Italy, which remained the most expensive market in the observed region at €180.91/MWh.
Friday’s trading again showed fragmentation across Southeast Europe’s electricity market. The region split into three price layers: Italy and the Hungary-Croatia-Slovenia-Austria cluster at roughly €173-181/MWh; Romania, Bulgaria and Serbia around €168-170/MWh; and southern Balkan markets below €163/MWh.
Serbia’s day-ahead curve jumps across peak and off-peak hours
The largest move came from Serbia. SEEPEX base-load prices increased from €132.0/MWh on Thursday to €167.7/MWh on Friday, with the rise extending across the full daily curve rather than being limited to evening hours.
The peak block rose from €127.3/MWh to €160.2/MWh, while off-peak prices increased from €136.7/MWh to €175.3/MWh. Serbia’s minimum hourly price climbed from €75.3/MWh to €130/MWh and its maximum increased from €200/MWh to €231/MWh.
The minimum occurred around hour 11, while the daily maximum was reached around hour 20. The change reflected a broad tightening of Serbia’s power balance, with the entire price floor moving higher rather than an isolated evening scarcity event.
Lower demand but weaker generation leaves Serbia importing
The increase occurred despite lower Serbian electricity consumption on Friday’s delivery day profile. Average demand fell to approximately 3.735 GW from 3.981 GW a day earlier, while generation declined more sharply from around 3.609 GW to 3.344 GW.
As a result, Serbia became a net importer of approximately 391 MW compared with around 372 MW the previous day. Scheduled commercial flows also reflected regional interconnections: Serbia imported about 349 MW from Bulgaria, 203 MW from North Macedonia and 110 MW from Hungary on a base-load basis.
At the same time, Serbia exported around 146 MW towards Croatia, 107 MW towards Romania and 75 MW towards Montenegro. The flows illustrated that cross-border schedules do not always align with straightforward day-ahead price differentials because legacy capacity rights, bilateral positions and uncoupled borders continue to limit full spot-market integration.
Hungary posts HUPX above €174 with Paks restart timeline in focus
HUPX base-load reached €174.1/MWh while the daily curve showed an unusual structure for peak versus off-peak pricing. The peak block averaged just €169.9/MWh compared with €178.3/MWh for off-peak hours.
The minimum hourly price remained relatively high at €135.7/MWh and the evening maximum reached €222.7/MWh. The inversion between peak and off-peak prices matched a summer pattern linked to high solar penetration, where photovoltaic output suppresses daytime peak prices and post-sunset ramps shift expensive periods into what is traditionally treated as off-peak time.
Hungary’s system balance stayed tight: consumption was around 4.137 GW while domestic generation reached only approximately 2.882 GW, leaving net imports of around 1.255 GW as dependency on external supply.
A key factor was restricted nuclear availability at Paks, following exceptionally low Danube water levels affecting cooling conditions after which Hungary expects affected units to restart gradually from 23 August and potentially reach full output by 27-28 August after emergency works aimed at increasing cooling-water levels.
Cross-border flows shift as German prices rise and imports increase
The stronger German market altered regional cross-border economics during Friday trading for delivery on 21 August. With German day-ahead prices reaching €169.56/MWh, the HU-DE spread narrowed to just €4.50/MWh.
Average imports from the Austria-Slovakia core into Hungary and Slovenia fell to around 1.051 GW, about 261 MW lower than the previous day. The wider Hungary and SEE system remained a net importer of around 923 MW versus 693 MW in the prior session.
Regional consumption increased by approximately 358 MW to around 32.49 GW despite higher forecast solar output of about 8.35 GW, nearly 0.95 GW higher than the previous day; wind generation stayed broadly unchanged at around 1.96 GW.
Northern corridor trades: Romania-Bulgaria convergence and transit role
Romania and Bulgaria nearly converged on price levels at €169.58/MWh and €169.08/MWh respectively on Friday’s delivery day profile for day-ahead trading data cited in the source material.
Romania’s national balance was close to neutral with demand of around 5.73 GW, generation of approximately 5.71 GW and net imports of only about 24 MW; however, it masked substantial cross-border activity including scheduled exports of about 1.06 GW to Hungary on a base-load basis alongside imports of approximately 1.01 GW from Bulgaria.
During peak hours exports towards Hungary rose to roughly 2.62 GW while imports from Bulgaria approached 1.79 GW, supporting Romania’s role as a transmission corridor moving electricity from the Balkans toward Hungary and Central Europe rather than only balancing its domestic market.
Bulgaria exports more while Kozloduy Unit 5 reduces output
Bulgaria remained one of the region’s largest exporters with generation of approximately 5.08 GW exceeding domestic consumption of around 3.95 GW for average net exports of roughly 1.13 GW.
Base-load commercial flows included about 1.01 GW towards Romania, 349 MW towards Serbia and 180 MW towards North Macedonia on Friday’s delivery schedule cited in the source material.
Bulgaria’s balance became more sensitive to hydrology conditions as Kozloduy Unit 5 was scheduled to reduce output by around 120 MW on 21 August, citing exceptionally low Danube water levels as its first weather-related reduction of this type in its operating history within the plant context provided.
Greece remains an exporter with large intraday solar-driven spreads
HENEX, Greece’s benchmark for day-ahead pricing referenced in the source material, increased by more than €16/MWh but settled relatively low at €162.73/MWh—around €11.3/MWh below HUPX and about €6.4/MWh below Bulgaria.
Greece also remained a significant exporter: average generation reached approximately 7..87 GW against demand of around 6..90 GW for net exports close to 968 MW.
The commercial schedule showed base-load flows of about 308 MW towards Bulgaria, 184 MW towards Albania, 354 MW towards North Macedonia and 171 MW towards Italy; during peak hours flows from Greece to Bulgaria increased to roughly 752 MW.
The hourly HENEX curve reflected solar impacts: the minimum price fell to just €76..7/MWh around hour 12, while the evening maximum reached €223..6/MWh around hour 19.
Macedonia stays cheapest among major markets while acting as transit hub
A similar intraday pattern appeared in North Macedonia where MEMO remained the cheapest market in the region at €140..58/MWh for Friday delivery data cited in the source material.
The midday minimum fell to only €50..3/MWh while the evening maximum reached €208./MWh.