Week 23 saw Southeast Europe’s cross-border electricity flows increase, with regional net imports up 9.1% week on week to 1.22 TWh. Higher demand and weaker renewables contributed to greater reliance on balancing across borders. The change coincided with continued price fragmentation across the region.
Regional import volumes broaden across key markets
Net import growth was spread across multiple countries. Hungary raised net imports by 64.7% to 179.75 GWh, Romania increased imports by 34.0%, and Croatia lifted net imports by 18.5%. Italy remained the largest net importer at 950.91 GWh, despite a 14.1% weekly decline in its import volume.
Greece and Türkiye stayed as net exporters during the week, but both reduced export volumes compared with the prior period. The shift in net positions contributed to a broader pattern of cross-border balancing needs across Southeast Europe. Interconnector flows therefore remained central to how power moved between zones.
Price spreads persist across Southeast Europe bidding zones
Despite higher regional imports, prices remained fragmented across SEE markets. Italy averaged €128.09/MWh, while Greece averaged €89.25/MWh. Serbia posted an average of €99.63/MWh, Bulgaria €100.83/MWh, Romania €102.23/MWh, Hungary €103.15/MWh, and Croatia €99.29/MWh.
The size of the spreads created theoretical arbitrage opportunities, though realized outcomes depend on interconnector availability, congestion, and scheduling rules. Transmission capacity determines whether power can be moved effectively between price zones under prevailing constraints. This link between prices and physical transfer capability shaped trading conditions during Week 23.
Transmission capacity and cross-border routes affect commercial outcomes
Interconnectors function as a financial asset when cross-zonal price differences persist alongside workable transfer conditions. Traders securing capacity across constrained borders can capture spreads, while generators with export access can improve realized pricing in receiving markets. Industrial buyers can structure cross-border supply to reduce procurement costs where routing is available.
Italy illustrated the interaction between pricing and flows, remaining the highest-priced SEE market and the largest net importer during Week 23. Lower-cost generation in Balkan markets has value when it can reach Italian or Central European demand centres, but persistent price differences indicate that interconnection alone does not fully equalise markets.
Hungary’s role as a Central SEE hub supports import demand
Hungary’s import increase was also tied to its position within the regional network of interconnections. As a Central SEE hub linked to Austria, Slovakia, Croatia, Serbia and Romania, Hungary can transmit price signals across multiple borders during periods of shifting net positions. Its weekly average price of €103.15/MWh kept it within the upper cluster of regional averages.
The same pattern aligns with cross-border trading interest as import demand rises in response to higher demand and weaker renewables elsewhere in the region during Week 23 . Capacity availability and scheduling continue to influence how quickly market participants can respond to those changes.
Renewables variability increases the need for flexible cross-border transfers
Wind and solar variability can rapidly change a country’s net position, affecting whether it needs imports or exports over short timeframes. A system with surplus solar at midday may require imports later in the day, while wind-heavy conditions can shift from export to import depending on weather patterns . Cross-border capacity therefore supports flexibility beyond day-ahead trading.
This flexibility role is reflected in how interconnector capacity interacts with changing generation profiles across national systems during periods like Week 23. The ability to move power between zones becomes relevant for balancing needs when domestic production swings faster than demand adjustments.
Policy focus on grid reinforcement and capacity allocation
For TSOs and regulators, Week 23 reinforced attention on grid reinforcement, market coupling, intraday liquidity, and transparent capacity allocation processes . These elements influence how transmission constraints are managed and how quickly market participants can access cross-border transfer capability when prices diverge.
The same considerations apply for investors evaluating generation projects alongside grid access and export optionality . A project located in a constrained node may have different value compared with an asset connected to more liquid cross-border routes under prevailing congestion patterns.
Southeast Europe is not yet one integrated price zone, but it operates increasingly as an interconnected balancing region where interconnector constraints are visible in market outcomes . As imports rise and price spreads persist, transmission capacity carries more strategic and financial value for participants managing flows between bidding zones.
