Electricity prices rose sharply across Southeastern Europe during the summer of 2024, exposing structural weaknesses in the regional power market. European regulators began considering new measures intended to reduce the risk of similar disruptions. The assessment was linked to concerns about prolonged price volatility.
In response to instability concerns, the European Commission asked ACER to investigate the causes and propose solutions. ACER prepared a detailed report for the Energy Union Task Force. The document set out recommendations covering electricity infrastructure, market integration and system flexibility.
Countries assessed after 2024 price spikes
The analysis focused on countries most affected by the 2024 price spikes, including Slovenia, Croatia, Hungary, Romania, Bulgaria and Greece. Austria and Slovakia were included as comparison markets reflecting central European electricity dynamics. This approach was used to contrast regional outcomes across different parts of Europe.
ACER identified evening peak-demand periods as a key point of stress in the regional system. The report cited a lack of flexibility in energy systems during those hours, particularly after solar power production declined. It also highlighted constraints affecting cross-border electricity movements.
Flexibility gaps and transmission limits during peak demand
ACER pointed to limited transmission capacity between countries as a factor that constrained imports of lower-cost electricity from other parts of Europe. Planned maintenance works on transmission networks were also described as adding pressure by reducing cross-border flows. Together, these elements contributed to conditions during the period when demand peaked in the evening.
While electricity prices became more stable in 2025 compared with the previous summer, ACER said price differences between Southeastern Europe and central Europe persisted into early 2026. The agency said this indicated ongoing market challenges rather than only temporary disruptions. The findings were presented as part of the broader review requested by the European Commission.
Recommendations for infrastructure, balancing and integration
ACER concluded that more efficient use of existing infrastructure could have helped ease pressure on regional electricity systems during the crisis. At the same time, it stressed that expanding interconnection capacity alone would not be sufficient without additional investments in flexible energy resources and modern balancing technologies. The report therefore linked resilience measures to both grid capability and operational flexibility.
To strengthen market resilience, ACER recommended faster deployment of network-enhancing technologies, including advanced transmission equipment and dynamic line rating systems. It also called for stronger regional cooperation for managing electricity networks, improved coordination of maintenance schedules and broader use of corrective operational measures. Additional proposals addressed strategic network investments across Southeastern Europe.
The report also urged removing barriers that prevent smaller market participants from entering the sector. It further supported technologies intended to increase system flexibility and efficiency. Alongside these steps, ACER emphasized continued efforts toward European electricity market integration.
ACER underlined the need to maintain cross-border transmission requirements and expand flow-based market mechanisms. It also called for strengthening electricity market coupling with neighboring non-EU countries. These measures were presented as part of efforts to support a more stable and interconnected regional energy system.
