Electricity grids and cross-border interconnectors

Electricity grids and cross-border interconnectors can transmit support, vulnerability and disruption across borders. The statecraft instrument is a government or authorised-operator decision concerning supply, synchronisation, infrastructure, cyber operations or physical attack. Interconnection itself normally supports trade, flexibility and mutual assistance. It creates leverage only where a state or operator controls a consequential and insufficiently replaceable function.

System layers and control

Transmission networks move bulk power; distribution networks deliver it to customers. Alternating-current systems sharing one synchronous area operate at a common frequency under coordinated rules. High-voltage direct-current links can connect systems without synchronising them. Commercial schedules, physical flows, ownership, dispatch, balancing and emergency assistance are separate layers.

Interconnector capability is also asymmetric in practice. Nameplate capacity does not establish how much power can move in either direction at a given time. Congestion, outages, reserve requirements, converter limits and domestic network constraints can reduce usable capacity. A claim of leverage therefore needs operational capacity, not merely a mapped connection.

Power systems must balance supply and demand continuously. Storage is increasingly available through batteries, pumped hydro and other technologies, but remains constrained by duration, location and power capacity. Demand response, dispatchable generation, reserves, storage and interconnection can each provide flexibility. It is therefore inaccurate to describe electricity as barely storable or every interconnector as an exploitable dependency.

Statecraft mechanisms

Provision and emergency support can preserve critical services or demonstrate coalition commitment. Export restriction can deny power where a state controls supply or an interconnector. Synchronisation can reconfigure long-term network alignment. Cyber operations can disrupt control systems, while physical attacks can degrade generation or transmission during war. Each pathway requires a different authority, operator and evidential test.

The 23 December 2015 cyber incident affected three Ukrainian distribution companies and approximately 225,000 customers, according to the United States incident alert. That alert establishes the incident facts. A later US government advisory attributed the 2015 and 2016 campaigns to Russian state-sponsored actors. Incident, attribution and strategic purpose must remain separate propositions.

On 16 March 2022, Ukraine and Moldova synchronised on a trial basis with Continental Europe following an emergency request and technical assessment. On 9 February 2025, Estonia, Latvia and Lithuania completed synchronisation with Continental Europe after disconnecting from the Russian and Belarusian frequency area. The Baltic project was a planned, EU-backed integration and resilience programme. Its completion does not prove that the prior arrangement had already produced a realised coercive cut-off.

Resilience and limits

Exposure depends on capacity, directionality, market rules, operator authority, redundancy and restoration capability. Interconnection may diversify supply and share reserves rather than create dependence. Storage, alternative generation, demand response, islanding, spare equipment and reciprocal assistance all alter leverage.

Physical attacks on electricity infrastructure require separate evidence for target, military purpose, civilian and economic effects, attribution and legal status. The label economic warfare cannot substitute for analysis under the applicable law of armed conflict.

See also

Cross-border electricity weaponisation · Critical-infrastructure cyber operations · Supply-chain resilience

Sources

1. International Energy Agency, Electricity Grids and Secure Energy Transitions (2023).
2. International Energy Agency, Secure Energy Transitions in the Power Sector (2021).
3. International Energy Agency, Batteries and Secure Energy Transitions (2024).
4. Cybersecurity and Infrastructure Security Agency, "Cyber-Attack Against Ukrainian Critical Infrastructure", ICS Alert IR-ALERT-H-16-056-01, 25 February 2016.
5. Cybersecurity and Infrastructure Security Agency, "Understanding and Mitigating Russian State-Sponsored Cyber Threats to U.S. Critical Infrastructure", 11 January 2022.
6. European Network of Transmission System Operators for Electricity, "Continental Europe Successful Synchronisation with Ukraine and Moldova Power Systems", 16 March 2022.
7. European Network of Transmission System Operators for Electricity, "Successful Synchronization of the Continental European Electricity System with the Systems of the Baltic Countries", 9 February 2025.
8. European Commission, "Baltic Energy Market Interconnection Plan", checked 29 July 2026.