1. Introduction

Gas-network repurposing for hydrogen means converting existing natural-gas pipelines, compressor stations, metering facilities and associated infrastructure so that they can transport hydrogen instead of, or in some cases alongside, natural gas. It is becoming an important legal and regulatory issue because repurposing can reduce the need for entirely new hydrogen pipelines while also creating questions about safety, property rights, network access, costs, stranded gas assets and the future gas supply system.

The modern legal approach is increasingly based on integrated gas-and-hydrogen network planning, rather than treating hydrogen infrastructure as completely separate from the existing gas system. The EU's 2024 Hydrogen and Decarbonised Gas Market package establishes dedicated rules for hydrogen networks and the transition of natural-gas systems toward renewable and low-carbon gases. EU Member States were required to transpose the package by 5 August 2026. (EUR-Lex)

Germany provides one of the clearest examples of a statutory framework expressly facilitating conversion of existing gas infrastructure into hydrogen infrastructure. Its Energy Industry Act (EnWG) gives priority, where technically and economically possible, to converting existing pipeline infrastructure rather than constructing entirely new pipelines. (Gesetze im Internet)

2. Meaning of Gas Network Repurposing

Repurposing is different from simply adding hydrogen to natural gas.

It may involve:

Conversion of a natural-gas pipeline into a dedicated hydrogen pipeline;

conversion of sections of a gas transmission network;

modification or replacement of valves, compressors and seals;

modification of metering and control systems;

conversion of underground storage facilities;

conversion of distribution networks;

creation of hydrogen interconnections with existing gas infrastructure; and

eventual decommissioning of gas infrastructure that is no longer required.

The legal question is therefore not simply whether a pipeline can technically carry hydrogen. The central question is:

Under what legal conditions may an existing publicly regulated gas asset be withdrawn from natural-gas service and placed into hydrogen service?

That question involves energy regulation, property law, safety law, environmental law, planning law, tariff regulation and competition law.

3. Why Existing Gas Networks Are Legally Important

Existing gas networks represent substantial sunk infrastructure investment.

Repurposing can potentially:

reduce construction requirements;

reduce land acquisition;

use existing pipeline corridors;

accelerate hydrogen infrastructure development;

reduce duplication of infrastructure;

preserve the economic value of existing assets; and

connect hydrogen producers with industrial consumers.

However, repurposing also removes infrastructure from the natural-gas system.

This creates a legal balancing exercise:

Hydrogen infrastructure needs ↔ continuing natural-gas demand ↔ security of supply ↔ consumer protection.

Germany's EnWG expressly reflects this balancing principle. Existing transmission infrastructure can be converted to hydrogen, but the remaining gas network must continue to satisfy the applicable planning framework and remaining natural-gas transport requirements. (Gesetze im Internet)

4. EU Legal Framework

The principal European framework is the EU Hydrogen and Decarbonised Gas Market Package, consisting principally of:

Directive (EU) 2024/1788; and

Regulation (EU) 2024/1789.

The Directive establishes rules concerning the organisation, operation and access of hydrogen systems, including hydrogen transmission, distribution, supply and storage. It also addresses the transition of the natural-gas system toward renewable and low-carbon gases. (EUR-Lex)

The framework is significant because it moves hydrogen from a largely policy-driven area into a more structured network-regulation model.

Important legal principles include:

A. Third-party access

Hydrogen networks are increasingly treated as regulated infrastructure rather than private pipelines that can simply be operated without access obligations.

B. Non-discrimination

Network operators must provide access according to transparent and non-discriminatory rules.

C. Unbundling

Ownership and operation of networks must be separated, to an appropriate degree, from competitive production and supply activities.

D. Independent regulation

National regulatory authorities play an important role in network access, tariffs, certification and market regulation.

E. Integrated infrastructure planning

Gas and hydrogen infrastructure planning increasingly needs to consider the interaction between:

declining natural-gas demand;

hydrogen demand;

renewable-gas development;

storage;

cross-border infrastructure; and

security of supply.

5. German Legal Framework: EnWG

Germany is particularly important because the Energiewirtschaftsgesetz (EnWG) expressly addresses conversion of gas infrastructure.

Section 15a and related provisions establish a joint gas-and-hydrogen network-development planning system. The Bundesnetzagentur explains that gas transmission operators and regulated hydrogen transmission operators prepare a nationwide network-development plan covering a 10–15 year planning period. (Federal Network Agency)

The framework specifically provides that:

conversion of existing pipeline infrastructure to hydrogen should generally have priority over construction of new pipelines where conversion is technically and economically possible.

That is a major legal recognition of repurposing as a preferred infrastructure pathway. (Gesetze im Internet)

6. Hydrogen Core Network

Germany's EnWG also establishes a Hydrogen Core Network (Wasserstoff-Kernnetz).

Section 28q provides the legal basis for developing a nationwide hydrogen network connecting:

major hydrogen-production facilities;

import points;

hydrogen consumers;

storage facilities; and

major industrial demand centres.

The legislation specifically allows existing infrastructure capable of being converted for hydrogen transportation to form part of this development. (Gesetze im Internet)

This represents an important change in infrastructure law:

Old model

Natural-gas network → separate hydrogen network

Emerging model

Existing gas infrastructure → assessment → selected pipelines repurposed → integrated hydrogen network

Germany's government states that approximately 60% of the planned hydrogen core network involves conversion of existing natural-gas pipelines, demonstrating the practical importance of repurposing. (Economic Affairs Ministry)

7. Legal Test for Repurposing

A proper legal framework should normally require several assessments.

7.1 Technical feasibility

The operator must determine whether the particular pipeline is suitable for hydrogen.

Hydrogen can create technical problems involving:

hydrogen embrittlement;

leakage;

seals;

valves;

compressors;

welding;

pressure;

material compatibility;

measurement equipment.

Therefore, regulatory permission should not be based merely on the pipeline's existing gas certification.

7.2 Remaining gas-network capacity

This is one of the most important legal requirements.

A transmission pipeline cannot simply be removed from the gas network if doing so would threaten remaining consumers.

German law therefore requires the operator to demonstrate that the relevant gas infrastructure can be removed from the gas transmission system while the remaining system continues to meet the applicable requirements. (Gesetze im Internet)

This creates a legal principle of:

"No repurposing without adequate residual gas-system planning."

7.3 Economic efficiency

Regulators should compare:

repurposing an existing pipeline;

constructing a new hydrogen pipeline;

retaining the gas pipeline;

partially repurposing it;

constructing alternative hydrogen infrastructure.

The legally preferable option may therefore depend on the cost and system benefits of each alternative.

8. Safety Regulation

Hydrogen conversion creates a new regulatory risk because a pipeline originally authorised for natural gas is being used for a different substance.

Germany's federal government explains that conversion constitutes a significant change under its high-pressure gas pipeline safety framework because the transported medium changes. The operator must therefore develop an individual catalogue of technical measures with an expert and progressively implement those measures under supervision. (Economic Affairs Ministry)

A legal framework should consequently require:

technical inspection;

material compatibility assessment;

pressure testing;

leak detection;

emergency procedures;

compressor assessment;

valve replacement where necessary;

hydrogen-compatible metering;

inspection and maintenance procedures; and

certification before commercial operation.

9. Property and Wayleave Rights

One of the most interesting legal issues is whether an existing right to construct and operate a gas pipeline also permits hydrogen transportation.

Germany has expressly addressed this issue.

Section 113a EnWG provides that existing agreements, easements and other rights permitting construction and operation of gas-supply pipelines are, subject to the statutory conditions, interpreted to include pipelines transporting hydrogen. Existing gas wayleave agreements can therefore continue to support hydrogen infrastructure. (Gesetze im Internet)

This is legally significant because otherwise repurposing thousands of kilometres of pipelines could require extensive renegotiation of:

easements;

landowner agreements;

municipal wayleaves;

rights-of-way; and

planning permissions.

A statutory continuity rule can substantially reduce transaction costs.

10. Network Access and Competition Law

Repurposed hydrogen infrastructure can become a bottleneck.

Suppose one company owns the only hydrogen pipeline connecting:

Hydrogen producer → industrial consumer.

The owner could potentially discriminate against competing producers or consumers.

Consequently, hydrogen regulation needs:

third-party access;

transparent tariffs;

capacity-allocation rules;

non-discrimination;

balancing rules;

congestion management; and

regulatory supervision.

Germany's EnWG requires regulated hydrogen network operators to provide third parties with connection and network access under reasonable and non-discriminatory conditions. (Gesetze im Internet)

11. Case Law

There is still relatively limited case law specifically concerning natural-gas pipelines being converted into hydrogen pipelines, because large-scale hydrogen network regulation is relatively new.

Therefore, existing gas and energy-network cases are important because they establish general principles that apply to future hydrogen infrastructure.

Case 1: Commission v Germany, C-718/18

Court: Court of Justice of the European Union
Judgment: 2 September 2021
Subject: Gas and electricity network regulation and regulatory independence.

The Court held that EU energy law requires effective separation between network operation and competitive production/supply activities. It also emphasised the importance of independent national regulatory authorities. (InfoCuria)

Relevance to hydrogen

When existing gas infrastructure is converted into hydrogen infrastructure, the same competition concerns arise.

For example, a network operator should not be able to use control over a repurposed pipeline to favour its own hydrogen-production or hydrogen-supply activities.

Thus, unbundling principles remain important after repurposing.

Case 2: VEMW and Others, C-17/03

Court: CJEU
Judgment: 7 June 2005.

The case concerned discriminatory access to electricity transmission capacity. The Court interpreted EU network-access principles broadly and held that non-discrimination requirements are not restricted merely to technical rules. (curia)

Relevance to hydrogen

The principle has broader significance for hydrogen networks.

If hydrogen infrastructure becomes regulated infrastructure, access rules cannot be designed in a way that effectively favours:

incumbent producers;

affiliated suppliers;

particular industrial users; or

preferred market participants.

Repurposing therefore needs a fair-access framework, not merely technical conversion rules.

Case 3: Commission v Germany, C-718/18 — Regulatory Independence

A second important aspect of C-718/18 concerns the independence of national regulators.

The Court found that EU law requires national energy regulators to exercise their regulatory powers independently rather than being controlled through detailed governmental instructions concerning matters assigned to the regulator. (InfoCuria)

Application

For hydrogen repurposing, an independent regulator may need to determine:

whether a pipeline can be repurposed;

whether network access is discriminatory;

whether tariffs are justified;

whether investment is necessary;

whether capacity should be allocated;

whether an operator has complied with regulatory obligations.

This reduces the risk that infrastructure decisions are driven exclusively by the commercial interests of incumbent operators.

12. UK Legal Framework

The United Kingdom presents a somewhat different model.

The traditional gas network regulatory framework is based substantially on the Gas Act 1986, alongside Ofgem's regulatory powers and network licences.

The UK Government has been developing a specific economic regulatory framework for hydrogen pipeline networks. Its 2025 government response proposed legislation, licensing arrangements and a new hydrogen network code to create an economic regulatory framework for hydrogen pipeline infrastructure. (GOV.UK)

The important legal issue is therefore the transition from:

Gas Act-based regulation → dedicated hydrogen pipeline regulation.

The UK approach demonstrates that repurposing cannot be addressed only through engineering standards. A new regulatory architecture may be necessary concerning:

licensing;

network access;

investment;

tariffs;

network codes;

ownership;

safety; and

regulatory oversight.

13. Planning and Environmental Law

Repurposing can reduce environmental impacts because an existing pipeline corridor may be retained.

However, this does not automatically mean that all environmental approvals disappear.

A conversion may require consideration of:

environmental impact;

protected habitats;

construction works;

compressor modifications;

water impacts;

land disturbance;

emergency safety zones;

hazardous-substance regulation; and

planning consent.

The legal framework should distinguish between:

minor technical modifications

and

substantial physical or operational changes.

This allows regulators to avoid unnecessary duplication while retaining environmental safeguards.

14. Tariff and Cost Allocation

A major legal problem concerns who pays for conversion.

Possible approaches include:

A. User-pays model

Hydrogen users pay the costs of conversion.

B. Network-socialisation model

Costs are spread across network users.

C. Public funding

Government supports strategic infrastructure.

D. Hybrid model

Public funding supports initial conversion while users pay regulated network charges.

The choice affects:

electricity and gas consumers;

hydrogen producers;

industrial consumers;

network operators;

taxpayers; and

competing infrastructure providers.

Germany's framework uses regulatory planning and need assessment to determine which hydrogen infrastructure qualifies as necessary. For certain projects, a positive government hydrogen-support decision creates a presumption of network necessity. (Gesetze im Internet)

15. Decommissioning and Stranded Assets

Repurposing creates an unusual regulatory problem.

A gas pipeline may have originally been financed on the assumption that it would operate for several decades.

If it is converted to hydrogen earlier than anticipated:

Who bears the remaining unrecovered investment?

Possible legal mechanisms include:

accelerated depreciation;

stranded-asset compensation;

regulated asset-base adjustments;

transfer of assets;

government compensation;

hydrogen-network financing; or

cross-subsidisation.

The law must prevent consumers from paying twice:

once for the original gas infrastructure and again for unnecessary replacement gas infrastructure.

This is why integrated network planning is legally important.

16. Gas Security and Hydrogen Transition

Repurposing should also be connected with gas-security law.

If ten pipelines are converted to hydrogen, the regulator should assess whether the remaining network can:

satisfy peak demand;

maintain pressure;

supply essential consumers;

meet emergency requirements;

accommodate storage constraints; and

withstand infrastructure failures.

Germany's network-development framework specifically requires consideration of safe and reliable network operation and security of supply. (Federal Network Agency)

Thus:

Hydrogen transition law cannot operate independently of gas-security law.

17. Regulatory Model for India

For India, a comparable framework could be developed around the existing gas-pipeline regulatory structure while creating dedicated hydrogen provisions.

Relevant institutions would potentially include:

Ministry of Petroleum and Natural Gas;

PNGRB;

BIS;

PESO;

environmental authorities;

state authorities; and

relevant pipeline operators.

A future Indian framework could establish:

Stage 1 — Pipeline identification

Identify pipelines suitable for hydrogen conversion.

Stage 2 — Technical assessment

Assess metallurgy, pressure, valves, compressors and leakage.

Stage 3 — Gas-security assessment

Determine whether removing the pipeline from gas service affects existing consumers.

Stage 4 — Hydrogen-demand assessment

Identify industrial clusters, refineries, fertiliser plants, steel plants and hydrogen hubs.

Stage 5 — Regulatory approval

Create a dedicated conversion approval procedure.

Stage 6 — Safety certification

Require independent technical verification.

Stage 7 — Network access

Provide regulated third-party access where the infrastructure has public-network status.

Stage 8 — Tariff regulation

Establish transparent hydrogen transportation charges.

Stage 9 — Monitoring

Require periodic inspection and reporting.

Stage 10 — Decommissioning

Create rules for pipelines that eventually become unsuitable for either gas or hydrogen.

18. Key Legal Principles

A mature hydrogen repurposing framework should therefore contain at least ten principles:

19. Major Legal Challenges

The principal unresolved legal questions include:

1. Ownership

Who owns a repurposed pipeline after conversion?

2. Asset valuation

How should its regulated value change?

3. Consumer compensation

Should existing gas consumers receive protection from conversion-related costs?

4. Safety standards

What technical standards should determine hydrogen compatibility?

5. Access

Should hydrogen pipelines have mandatory third-party access?

6. Market power

How should dominant hydrogen pipeline owners be regulated?

7. Cross-border transport

How should hydrogen pipelines crossing national borders be regulated?

8. Existing easements

Does a gas pipeline right automatically extend to hydrogen?

9. Decommissioning

Who pays if the pipeline becomes unusable?

10. Regulatory uncertainty

How should law accommodate future hydrogen technologies without requiring repeated legislative amendments?

20. Conclusion

Gas-network repurposing for hydrogen is developing into a distinct field of energy infrastructure law. The central legal transformation is from a traditional natural-gas regulatory model toward a multi-gas and hydrogen infrastructure framework.

The European framework establishes common rules for hydrogen infrastructure, while Germany has gone further by expressly integrating gas and hydrogen network planning and providing legal mechanisms for converting existing gas infrastructure. (EUR-Lex)

Germany's approach is particularly significant because it addresses several practical legal obstacles simultaneously: network planning, conversion priority, residual gas demand, hydrogen-core-network development, third-party access and continuity of wayleave rights. (Gesetze im Internet)

The existing case law, especially Commission v Germany (C-718/18) and VEMW (C-17/03), provides broader principles concerning independent regulation, effective unbundling and non-discriminatory network access. (InfoCuria)

The emerging legal principle can therefore be stated as:

Repurposing a gas network for hydrogen should be legally permitted where it is technically safe, economically justified, compatible with remaining gas-system requirements, environmentally compliant, and subject to transparent and non-discriminatory network regulation.

This makes hydrogen pipeline repurposing not merely an engineering conversion, but a regulated legal transition of critical energy infrastructure.