QUEUE MANAGEMENT FOR CONSTRAINED CONNECTIONS

1. Introduction

Queue management for constrained connections refers to the legal, regulatory, and contractual mechanisms used to determine which electricity projects obtain access to limited transmission or distribution network capacity. The issue has become increasingly important as renewable generation, battery storage, data centres, electric-vehicle infrastructure, and other large loads seek grid connections faster than networks can accommodate them.

Great Britain provides a significant contemporary example. Historically, connections largely operated according to a first-come, first-served/first-ready principle, allowing projects already holding connection agreements to affect capacity available to later applicants. Ofgem identified stalled projects as a major cause of delay and approved stronger queue-management arrangements.

2. Purpose of Queue Management

A constrained electricity network cannot connect every proposed project immediately. Network operators must therefore allocate scarce capacity while maintaining system security, fairness, transparency, competition, and efficient network development.

Poor queue management can permit speculative or commercially unviable projects to reserve capacity for years. This may delay viable renewable-energy and storage developments and cause unnecessary network reinforcement.

Modern queue management consequently moves away from treating application date as the sole determinant of priority and increasingly considers whether projects are ready, progressing, and strategically required.

3. Great Britain Legal Framework

The principal transmission framework includes the Electricity Act 1989, transmission licences, the Connection and Use of System Code (CUSC), Ofgem regulation, and NESO connection procedures.

In November 2023, Ofgem approved CMP376, specifically WACM7, inserting a formal queue-management process into the CUSC framework. It applies milestones to new and relevant existing Construction Agreements and gives the system operator contractual termination powers where projects fail to satisfy required milestones.

The milestones require developers to demonstrate genuine progress. Failure can ultimately result in termination, releasing capacity for other projects. The government's Connections Action Plan expressly identified removal of stalled projects as necessary to prevent non-viable developments from delaying viable ones.

4. Gate 1 and Gate 2 Reform

The framework subsequently developed through TMO4+ connections reform. Ofgem approved the reforms in April 2025. Instead of preserving an unrestricted chronological queue, projects receiving firm Gate 2 treatment must satisfy readiness requirements and relevant strategic-alignment criteria. Projects failing those requirements may remain at Gate 1, without the same firm connection status.

The approach therefore represents movement toward “first ready and needed, first connected” allocation.

Legally, such prioritisation must nevertheless operate through published criteria, proper contractual and regulatory powers, consistent decision-making, and appropriate dispute mechanisms.

5. Case Law: R (Barstow and Others) v Green Generation Energy Networks Cymru Ltd [2026] EWHC 1698 (Admin)

Case Name/Citation: Barstow & Ors v Green Generation Energy Networks Cymru Ltd (Rev1) [2026] EWHC 1698 (Admin).

Facts: The proceedings concerned three proposed 132kV electricity connection projects linking renewable-energy developments with the National Electricity Transmission System. The claimants challenged aspects of the defendant's approach through judicial-review proceedings.

Legal Issue: The litigation concerned the legality of decisions and processes associated with major electricity connection infrastructure, including the proper public-law treatment of the projects.

Judgment: The High Court examined the challenged decisions against ordinary judicial-review principles and the relevant statutory and regulatory framework.

Legal Principle/Ratio: Electricity connection decisions made by bodies exercising relevant public or statutory functions may be scrutinised for lawfulness, procedural fairness, rationality, and compliance with governing powers.

Significance: Although not a CMP376 queue-termination case, it demonstrates the wider judicial-review environment within which constrained grid-connection decisions operate.

6. Disputes and Procedural Fairness

Queue removal can have major commercial consequences because developers may have invested heavily in land, planning, financing, and equipment based upon expected connection dates. Accordingly, termination decisions require clear milestone evidence and consistent application.

Under CMP376 arrangements, disputes concerning relevant milestone evidence or exceptions can ultimately proceed through the CUSC dispute framework and electricity arbitration. This provides an important mechanism for challenging contested queue-management decisions.

7. Regulatory Significance

Effective queue management prevents capacity hoarding, speculative applications, inefficient network investment, and excessive connection delays. NESO states that projects failing agreed progress milestones can be terminated so capacity becomes available to projects capable of progressing.

The continuing importance of the problem is illustrated by Ofgem's 2026 proposals addressing rapidly increasing data-centre connection applications through commitment fees and additional milestones.

8. Conclusion

Queue management for constrained connections has evolved from passive chronological allocation toward active regulatory prioritisation of viable, ready, and system-relevant projects. Its legitimacy depends upon transparent criteria, contractual authority, proportional termination powers, procedural fairness, and effective dispute resolution. Properly designed queue management therefore functions not merely as an administrative mechanism but as an important instrument of electricity-market efficiency, network security, investment governance, and the net-zero transition.