1. Introduction

Energy resilience refers to the capacity of an energy system to anticipate, withstand, absorb, adapt to, and recover rapidly from disruptions. Such disruptions may arise from armed conflict, cyberattacks, terrorism, extreme weather, natural disasters, infrastructure failures, geopolitical disputes, supply-chain interruptions, market shocks, or failures of cross-border energy infrastructure.

International law does not contain one comprehensive treaty called an “International Energy Resilience Convention.” Instead, energy resilience is governed through a network of international treaties, customary international law, regional arrangements, investment law, trade law, environmental law, and institutional cooperation mechanisms.

The contemporary approach increasingly treats resilience as a component of energy security. The IEA distinguishes long-term energy security—adequate infrastructure and diversified supplies—from short-term resilience, which concerns the capacity of energy systems to cope with events exceeding ordinary planning assumptions and restore services rapidly. (IEA)

2. Major International Legal Frameworks

A. Energy Charter Treaty

The Energy Charter Treaty (ECT) 1994 is one of the most directly relevant international legal instruments for energy security and resilience. It establishes a framework for long-term international cooperation in energy and covers investment, trade, transit and dispute settlement. (Energy Charter)

Its resilience relevance arises particularly from:

protection of energy investments;

non-discrimination;

protection against certain non-commercial risks;

energy transit;

cross-border infrastructure;

dispute settlement;

cooperation concerning energy efficiency and environmental matters.

The ECT specifically addresses reliable international energy transit, which is important where electricity, gas or other energy resources cross several jurisdictions. (Energy Charter)

Legal significance

A resilient international energy system requires infrastructure that investors are willing to finance and maintain. Investment protection can therefore contribute indirectly to resilience by reducing political and regulatory risks.

At the same time, investment protection is not absolute. States retain regulatory powers, including measures concerning environmental protection and energy policy, subject to their applicable international obligations.

3. Cross-Border Electricity Cooperation

Modern electricity systems are increasingly interconnected. Consequently, resilience cannot always be achieved by individual states acting alone.

Cross-border electricity integration can provide:

emergency electricity imports;

shared reserve capacity;

balancing resources;

diversified generation;

mutual assistance;

access to renewable generation;

improved system flexibility.

The IEA identifies system operations, long-term planning and regional institutions as central components of effective cross-border electricity integration. (IEA)

International legal arrangements may therefore establish:

interconnector ownership;

operating responsibilities;

emergency assistance;

allocation of transmission capacity;

system-balancing rules;

information sharing;

cybersecurity cooperation;

liability arrangements;

dispute settlement.

The Energy Charter Secretariat has developed model agreements specifically for cross-border electricity projects, including intergovernmental and host-government electricity model agreements. (Energy Charter)

4. International Energy Agency Frameworks

The International Energy Agency (IEA) plays an important institutional role in energy security, although many of its resilience mechanisms operate through cooperation and policy coordination rather than conventional treaty obligations.

The traditional IEA emergency-response system focuses particularly on oil-security mechanisms and emergency stocks.

The broader resilience model now encompasses:

emergency reserves;

supply diversification;

infrastructure protection;

emergency planning;

cybersecurity;

physical security;

rapid restoration;

equipment stockpiling;

international assistance.

The IEA's 2026 analysis of Ukraine's energy-system resilience identifies ten practical lessons, including resilience-focused planning, physical hardening, emergency oil stocks, standardized critical equipment, continuity of data, cyber resilience and cross-border cooperation. (IEA)

Legal importance

These mechanisms demonstrate that energy resilience is increasingly moving from an exclusively national-security concept toward a cooperative international governance model.

5. International Environmental Law

Environmental law is another important pillar of energy resilience.

Energy infrastructure can create transboundary environmental risks. Examples include:

hydroelectric dams;

nuclear facilities;

oil pipelines;

gas pipelines;

offshore energy installations;

transmission infrastructure;

mining projects supplying energy systems.

International environmental law requires states to exercise due diligence where activities within their jurisdiction create risks of significant transboundary harm.

The Pulp Mills judgment is particularly important because the ICJ recognized the relevance of environmental impact assessment where proposed activities may cause significant transboundary environmental harm. (International Court of Justice)

Resilience connection

Environmental assessment contributes to resilience by identifying:

climate risks;

flood risks;

ecosystem vulnerabilities;

water-resource constraints;

cumulative infrastructure impacts;

transboundary consequences.

Thus, environmental assessment can operate as a preventive resilience mechanism.

6. Climate Change Law and Energy Resilience

The Paris Agreement and broader international climate regime are increasingly connected with energy resilience.

Climate change creates risks to:

electricity transmission;

generation facilities;

hydropower;

thermal power plants;

fuel infrastructure;

coastal energy facilities;

offshore infrastructure.

Resilience therefore has two dimensions:

Mitigation

Reducing greenhouse-gas emissions through:

renewable energy;

energy efficiency;

electrification;

low-carbon technologies.

Adaptation

Making energy infrastructure capable of surviving:

extreme heat;

floods;

droughts;

storms;

wildfires;

sea-level rise.

International climate law therefore complements conventional energy-security law by addressing the physical risks that climate change creates for energy systems.

7. WTO Law and Energy Resilience

International trade law also affects resilience.

Energy resilience frequently requires governments to procure:

transformers;

batteries;

solar panels;

wind turbines;

grid equipment;

semiconductors;

cables;

energy-storage technologies.

However, governments may face WTO disciplines when they impose discriminatory domestic-content requirements or subsidies.

An important case is Canada — Renewable Energy / Canada — Feed-in Tariff Program.

The dispute concerned Ontario's renewable-energy programme and domestic-content requirements associated with electricity-generation facilities using solar and wind technologies. (World Trade Organization)

The WTO proceedings are significant because they illustrate the legal tension between:

industrial policy + energy-security objectives

and

international trade obligations.

The WTO Appellate Body materials also discussed the relationship between government intervention and reliable electricity supply in the Ontario electricity market. (World Trade Organization)

Consequently, resilience-oriented procurement policies must be designed consistently with applicable trade obligations.

8. International Investment Law

Energy resilience requires substantial investment in:

power grids;

LNG terminals;

pipelines;

renewable generation;

batteries;

interconnectors;

nuclear facilities;

hydrogen infrastructure;

energy-storage systems.

International investment treaties can provide protections concerning:

expropriation;

fair and equitable treatment;

discrimination;

security and protection;

contractual rights.

However, investment law can also produce disputes where governments modify energy policy.

Case: Electrabel S.A. v. Hungary

In Electrabel S.A. v. Hungary, the dispute concerned a power purchase agreement involving the Dunamenti power plant and Hungary's restructuring of its electricity market in the context of EU state-aid requirements. The case arose under the Energy Charter Treaty. (Investment Policy Hub)

The tribunal ultimately decided in favour of Hungary in the proceedings identified by UNCTAD.

Resilience significance

The case demonstrates that energy resilience must coexist with:

regulatory change;

electricity-market reform;

competition law;

state-aid rules;

investor protection.

International energy law therefore seeks a balance between investment stability and legitimate regulatory adaptation.

9. International Law of Transboundary Infrastructure

Energy infrastructure often crosses national borders.

Examples include:

electricity interconnectors;

gas pipelines;

oil pipelines;

hydroelectric facilities;

offshore transmission systems;

hydrogen pipelines.

Such infrastructure creates a legal requirement for coordination between states.

International agreements can regulate:

construction;

ownership;

operation;

maintenance;

emergency procedures;

access;

tariffs;

environmental protection;

liability;

force majeure;

dispute settlement.

The Energy Charter framework specifically recognizes the importance of reliable cross-border energy transit. (Energy Charter)

10. Gabčíkovo-Nagymaros Project

One of the most important international cases involving energy infrastructure is:

Gabčíkovo-Nagymaros Project (Hungary/Slovakia), ICJ, 1997.

The dispute concerned a major hydroelectric project on the Danube established under a 1977 treaty between Hungary and Czechoslovakia. Hungary suspended and subsequently abandoned aspects of the project, while Czechoslovakia proceeded with a provisional solution. (International Court of Justice)

The ICJ considered:

treaty obligations;

necessity;

environmental concerns;

changed circumstances;

state responsibility;

sustainable development;

cooperation between states.

The Court concluded that Hungary was not entitled to suspend and abandon its treaty obligations in the manner it had done, while also finding legal problems with the conduct of Czechoslovakia. It required the parties to continue working through the treaty framework while taking account of changed factual circumstances and environmental considerations. (International Court of Justice)

Relevance to resilience

The case demonstrates an important principle:

Long-term energy infrastructure cannot be governed solely by short-term national interests; treaty commitments, environmental protection and continuing cooperation must be reconciled.

For modern interconnectors and regional electricity systems, this is highly relevant.

11. Pulp Mills and Preventive Resilience

Although Pulp Mills on the River Uruguay (Argentina v. Uruguay) was not an electricity case, its principles are highly relevant to energy infrastructure.

The ICJ dealt with a shared river and transboundary environmental risks. The Court emphasized procedural cooperation and environmental assessment for activities capable of causing transboundary harm. (International Court of Justice)

Application to energy

The principle can be applied to:

hydropower projects;

pipelines;

nuclear facilities;

offshore energy;

cross-border transmission lines.

A state planning infrastructure with significant transboundary effects should consider environmental risks and cooperate with affected states.

This represents preventive resilience: reducing the probability that infrastructure will produce cross-border disruption before the project becomes operational.

12. Trail Smelter Arbitration

The Trail Smelter Arbitration between the United States and Canada is a foundational authority concerning transboundary environmental harm.

The arbitration is widely associated with the principle that a state must not permit activities within its territory to cause serious environmental injury in another state. Modern scholarship identifies the case as an important foundation for international rules concerning prevention of transboundary harm. (Cambridge University Press)

Energy-resilience application

The principle is relevant to energy projects because infrastructure failures can produce consequences beyond national borders.

For example:

an accident at a cross-border energy facility;

pollution from an energy installation;

failure of a hydroelectric facility;

contamination from energy production;

damage to shared ecosystems.

International resilience therefore involves not merely protecting one's own energy system, but also preventing one's energy activities from creating risks for neighbouring states.

13. Cybersecurity and Energy Resilience

Modern energy systems are increasingly digital.

Critical infrastructure may depend on:

SCADA systems;

digital substations;

smart meters;

automated dispatch;

cloud infrastructure;

telecommunications;

artificial intelligence;

digital control systems.

Cyberattacks can therefore produce physical consequences, including electricity interruptions.

International cooperation increasingly focuses on:

cyber incident information sharing;

emergency communication;

technical standards;

attribution cooperation;

protection of critical infrastructure;

capacity building.

The IEA's recent resilience work expressly identifies cyber resilience and international threat-information sharing as important components of modern energy-system resilience. (IEA)

14. Regional Energy Governance

Regional organisations can provide more detailed resilience mechanisms than global treaties.

The European electricity system provides an important example of regional integration.

Cross-border integration can allow interconnected systems to:

share reserves;

import electricity during emergencies;

balance variable renewable generation;

diversify supply;

coordinate system operations.

At the same time, interconnectedness can transmit failures across borders. The IEA therefore identifies the need for coordinated reliability frameworks and real-time operational cooperation. (IEA)

This produces an important legal principle:

Interdependence creates both resilience and systemic risk.

International law must therefore regulate not merely access to interconnected infrastructure but also the responsibilities that accompany interconnection.

15. Emergency Energy Cooperation

A mature international resilience framework should provide mechanisms for emergencies before the emergency occurs.

Legal arrangements can establish:

Mutual assistance

States agree to provide electricity, fuel, equipment or technical personnel.

Emergency information sharing

States notify one another about:

supply disruptions;

cyber incidents;

infrastructure damage;

fuel shortages;

system instability.

Strategic reserves

States maintain:

oil reserves;

gas storage;

emergency electricity capacity;

spare transformers;

critical grid components.

Rapid restoration

Agreements can establish expedited customs and regulatory procedures for emergency equipment.

The IEA's 2026 resilience assessment specifically emphasizes pre-established mutual-assistance agreements with clear obligations and cost-sharing mechanisms. (IEA)

16. Energy Resilience and Armed Conflict

Armed conflict presents one of the most serious challenges to energy resilience.

Energy infrastructure may become a strategic target, including:

power plants;

substations;

transmission lines;

fuel storage;

pipelines;

refineries.

The experience of Ukraine has demonstrated the importance of physical hardening, decentralization, equipment stockpiles, rapid repair and international assistance. (IEA)

International humanitarian law also becomes relevant during armed conflict because the protection of civilian populations and civilian objects imposes legal constraints on military operations.

Thus, energy resilience intersects with:

international humanitarian law;

international security law;

state responsibility;

cybersecurity law;

investment law;

international cooperation.

17. Principles Underlying International Energy Resilience

Several principles can be identified across these frameworks.

1. Prevention

States should identify and reduce foreseeable risks before they cause major disruption.

2. Cooperation

Energy resilience increasingly requires cooperation between neighbouring states.

3. Information sharing

Early notification and technical information can reduce cascading failures.

4. Diversification

International law and policy can facilitate diversification of:

suppliers;

routes;

technologies;

generation sources.

5. Due diligence

States must exercise appropriate care where activities under their jurisdiction create foreseeable transboundary risks.

6. Regulatory flexibility

Energy regulation must be capable of adapting to technological, environmental and geopolitical changes.

7. Investment protection

Long-term resilience requires predictable investment conditions.

8. Environmental sustainability

Resilience cannot be separated from climate and environmental protection.

9. Mutual assistance

States should establish assistance mechanisms before crises occur.

10. Systemic responsibility

Interconnected states must consider how domestic energy decisions affect neighbouring systems.

18. Key Case Laws

The Vattenfall disputes are particularly useful when examining the interaction between environmental regulation, energy policy and investment protection, although the precise legal issues and outcomes differ between the proceedings.

19. Major Legal Challenges

Despite these frameworks, international energy resilience remains fragmented.

A. No universal resilience treaty

There is no single global treaty comprehensively establishing obligations for electricity, gas, oil, hydrogen and energy-storage resilience.

B. Fragmented jurisdiction

Energy infrastructure may simultaneously be subject to:

domestic energy law;

investment treaties;

environmental treaties;

WTO law;

regional electricity rules;

bilateral agreements.

C. Sovereignty concerns

States retain significant control over their energy resources and infrastructure. Consequently, international cooperation must coexist with national sovereignty.

D. Cybersecurity gaps

Cyber risks develop faster than many international legal regimes.

E. Climate uncertainty

Infrastructure designed according to historical climate conditions may become inadequate as extreme-weather patterns change.

F. Interdependence

Greater interconnection creates additional resilience through resource sharing but can also create cascading failures across borders. (IEA)

20. Future Development of International Energy Resilience Law

The future international framework is likely to develop around several areas:

Regional electricity-resilience agreements

Cross-border emergency electricity assistance

International cybersecurity standards

Strategic stockpiles of critical grid equipment

Common standards for interconnectors

Climate-resilient infrastructure requirements

International cooperation on battery and critical-mineral supply chains

Resilience requirements in international infrastructure financing

Mutual recognition of emergency technical personnel

International rules for offshore electricity networks

Hydrogen and renewable-energy corridor agreements

Improved international dispute-resolution mechanisms

The current direction of international practice is toward combining national resilience measures with regional and international cooperation, particularly for interconnected electricity and gas systems. (IEA)

21. Conclusion

International legal frameworks for energy resilience are multilayered rather than consolidated into a single legal instrument. The Energy Charter Treaty provides important rules concerning energy investment, trade and transit; international environmental law establishes preventive and transboundary obligations; WTO law regulates aspects of energy-related trade and procurement; investment law protects certain energy investments while permitting substantial regulatory space; and regional arrangements provide operational mechanisms for interconnected energy systems.

The jurisprudence of Gabčíkovo-Nagymaros, Pulp Mills, Trail Smelter, Electrabel, and WTO renewable-energy disputes demonstrates that resilience is not simply a question of maintaining physical infrastructure. It is also a question of treaty compliance, environmental due diligence, investment protection, regulatory flexibility, international cooperation and prevention of transboundary harm.

The emerging legal model can therefore be understood as a shift from traditional energy security, focused primarily on ensuring sufficient supply, toward systemic energy resilience, which asks whether energy systems can anticipate disruption, withstand shocks, maintain essential services, cooperate across borders and recover quickly after failure. The IEA's recent work, particularly its lessons from Ukraine, reinforces this broader conception of resilience. (IEA)

In legal terms, the central challenge for the future is to transform resilience from a policy objective into a structured system of international duties concerning prevention, cooperation, information sharing, emergency assistance, infrastructure protection and rapid recovery.