Voltage Surge Caused North Macedonia Blackout, European Grid Operators Report

Skopje, North Macedonia – A comprehensive investigation by the European Network of Transmission System Operators for Electricity (ENTSO-E) has pinpointed the cause of the widespread blackout that crippled North Macedonia last May: the national transmission system operated above its designated voltage limit. The final report by an expert panel, comprising representatives from various European grid operators, concluded that this voltage surge was the direct trigger for the outage, which left the country without power for roughly ninety minutes.

This incident, occurring on May 18, 2025, affected nearly 100% of electricity consumption between 04:59 and 06:27 Central European Summer Time. Significantly, the report notes that the rest of the continental European grid remained largely unaffected, highlighting a localized failure within North Macedonia's infrastructure. The immediate cause was identified as the disconnection of all 400/110 kV transformers, effectively isolating the 400 kV grid from the 110 kV network.

From a Macedonian perspective, this report is crucial not only for understanding the technical failure but also for implementing preventative measures. The expert panel's recommendations focus on a regional action plan for managing high-voltage situations and enhancing coordination among transmission system operators. This emphasizes the need for stronger collaboration, not just within North Macedonia but across Southeast Europe, to bolster the resilience of the region's power infrastructure. The event serves as a stark reminder of the interconnectedness of energy systems and the critical importance of robust voltage management and inter-operator cooperation to prevent future disruptions.