In the context of Southeast Europe (SEE), the electricity market faces significant challenges due to congestion, which has emerged as a critical factor influencing price volatility. This congestion affects the ability of neighboring markets to share resources effectively, leading to local price spikes instead of a more integrated regional response. As the region transitions towards increased reliance on renewable energy sources, the importance of cross-border capacity as a stabilizing mechanism becomes increasingly evident.
The European electricity market is fundamentally structured around the principle that trade can alleviate scarcity. However, this system relies heavily on the availability of interconnectors and effective market coupling. In many instances within SEE, while physical interconnectors exist, their operational and regulatory capacity often falls short of what is necessary during peak demand periods. This inadequacy results in significant price divergences that are not solely attributable to demand fluctuations or fuel price variations.
During the summer of 2024, SEE experienced severe price spikes driven by high temperatures and increased demand, compounded by a decline in solar generation after sunset. The inability to import lower-priced electricity from neighboring regions exacerbated the situation. According to ACER’s analysis, enhancing cross-zonal capacities in central Europe could have substantially reduced both the frequency and intensity of these price surges.
Quantitative assessments reveal that adhering to the legally mandated 70% capacity requirement could have mitigated around half of the most extreme price spikes observed. Moreover, implementing this rule could have led to an average reduction in peak prices by up to €78/MWh across central and southeast bidding zones. Such reductions represent a significant shift from “stress pricing” to “crisis pricing,” particularly impacting industrial consumers.
The strategic choices made by countries regarding energy scarcity directly affect their competitiveness. Instead of overbuilding domestic generation capacity—which can be costly and politically divisive—investing in interconnections and market integration presents a more sustainable solution. While overbuilding leads to underutilized assets, market integration fosters long-term economic efficiency through shared resources.
Persistent higher wholesale prices in SEE compared to Western European markets are partly due to structural factors, including generation mix disparities and limited nuclear or hydroelectric resources. However, the severity of price spikes is heavily influenced by cross-border constraints that isolate local markets from available regional surplus. This isolation not only hampers industrial competitiveness but also heightens political sensitivities surrounding electricity costs.
Effective management of capacity availability should be viewed as a fundamental policy tool rather than a mere technical consideration. In integrated markets, scarcity can be shared and moderated; conversely, fragmented markets impose local penalties for scarcity, leading to heightened volatility.
The discourse surrounding cross-zonal capacity must transcend compliance issues; it serves as a vital stability instrument. The 70% rule compels transmission system operators (TSOs) and regulators to prioritize interconnector capacity availability, thereby reducing the potential for structural bottlenecks that lead to market isolation. When implementation is lacking, volatility escalates; conversely, improved implementation fosters manageable volatility.
Furthermore, as renewable energy sources like wind and solar become more prevalent, net load volatility increases necessitating flexible imports and exports. Interconnectors act as essential balancing mechanisms; their constraints can lead to curtailment during surplus periods and price spikes during shortages. Conversely, when these connections are robust, renewables can be absorbed effectively across regions, alleviating both curtailment and high pricing pressures.
The early 2026 market dynamics illustrate this interaction clearly: prices initially dropped due to increased wind output but rebounded sharply when conditions tightened later in the month. The ability to transfer power across borders during critical periods will determine whether volatility remains manageable or escalates into crises.
As trading behavior shifts with increased liquidity and cross-border flows, traders capitalize on market volatility—a natural consequence of congestion economics where scarce interconnector capacity becomes highly valuable. Transparent market coupling and capacity allocation can ensure that congestion rents reflect genuine scarcity while incentivizing necessary investments; however, lack of transparency may lead to distortions and political friction.
Governance plays a crucial role in managing cross-border capacity as price insurance. TSOs must collaborate on calculating available capacity while regulators need to prevent excessive withholding under security pretexts. Effective market coupling must be operationalized rather than merely theoretical. Reports from the Energy Community indicate ongoing but uneven progress toward deeper integration and comprehensive market coupling—critical steps for reducing unnecessary exposure to volatility events in SEE.
Ultimately, if meeting the 70% requirement can yield peak pricing reductions of up to €78/MWh, then ensuring cross-border capacity availability emerges as one of the most impactful strategies for enhancing regional stability without necessitating new infrastructure investments. Connectivity serves as a vital component of price insurance within this evolving energy landscape.
The implications for policymakers in SEE are clear: addressing congestion management is not just about compliance but is integral to fostering industrial policy stability. Fluctuating electricity costs can significantly alter investment decisions for industries while affecting household economic conditions—placing cross-border capacity policy at the heart of economic resilience in the region.
