April trading patterns revealed a notable shift in cross-border electricity flows across Southeast Europe, with declining volumes and changing directional balances pointing to a gradual fragmentation of regional market integration.
Historically, SEE markets have relied on price arbitrage to drive cross-border exchanges, with lower-cost generation from the Western Balkans flowing toward higher-priced EU markets such as Italy, Austria and Hungary. In April, however, this mechanism weakened considerably. Despite persistent price spreads—averaging around €25–30/MWh between Western Balkan markets and neighboring EU zones—export flows did not respond proportionally.
One of the clearest signals was the reduction in exports toward Italy, where flows declined by approximately −333 MW on average, indicating weaker arbitrage efficiency. At the same time, exports toward Ukraine and Moldova increased modestly, reflecting a shift toward eastern demand centers rather than traditional EU-bound flows.
The key structural driver behind this shift is the introduction of carbon-related adjustments on cross-border electricity trade. The implementation of new carbon cost mechanisms has effectively altered the economics of exports by introducing additional charges on electricity entering EU markets. These costs are applied based on standardized emission assumptions rather than actual generation profiles, creating distortions in competitiveness.
As a result, electricity generated from low-cost but carbon-intensive sources in the Western Balkans faces reduced access to EU markets, even when price spreads remain favorable. More critically, the system does not fully differentiate between clean and fossil-based generation in neighboring countries, leading to unintended consequences for renewable exports as well.
The immediate effect has been a decline in overall cross-border trading activity, estimated at around −25% compared to previous periods, signaling a breakdown in traditional market coupling dynamics. This is particularly significant for export-oriented systems such as Montenegro and Bosnia and Herzegovina, where cross-border sales represent a key revenue stream.
At the same time, internal SEE flows have become more pronounced. Exchanges between Balkan markets—such as Serbia, Bosnia, North Macedonia and Albania—remain active, supported by geographical proximity and aligned regulatory frameworks. However, these flows are smaller in scale and less capable of absorbing surplus generation during high-output periods.
From a system perspective, this fragmentation introduces several risks. Reduced integration with EU markets limits the ability of SEE systems to export excess renewable generation, increasing the likelihood of curtailment. It also reduces access to cheaper imports during periods of tight supply, potentially increasing volatility.
Looking ahead, the trajectory of cross-border flows will depend heavily on regulatory alignment. Without mechanisms to recognize actual carbon intensity and integrate SEE markets more fully into EU frameworks, the region risks developing into a semi-isolated trading zone, characterized by lower liquidity and higher price volatility.