The UK's grid connection queue has been dramatically compressed through two mechanisms: a formal transmission-level amnesty (2022 to 2024) and the larger TMO4+ reform (from June 2025). Together they have cleared hundreds of gigawatts of stalled or speculative projects from the queue, beginning to free capacity at substations and transmission nodes across Great Britain. This tracker reports the current state of that clearing, what it means for sites that appeared constrained, and where to find the live data.
If a site you looked at a year ago was blocked because the grid connection queue was full, that picture may now have changed. For most of the last decade, the UK's grid connection queue was clogged with projects that had no realistic prospect of connecting: speculative applications holding positions without planning consent, viable land rights, or financing. The result was a queue that had grown to over 770 GW by early 2025, creating waiting times that stretched into the 2030s and beyond for many genuine developers (ENA Connections Data, 2025).
The response has come in two waves: a formal amnesty allowing transmission-connected projects to withdraw without penalty, followed by the structural TMO4+ reform that replaced the entire queue management framework. Understanding both, and the capacity they have returned to the system, is essential for any developer or community energy group screening sites in 2026.
What "connection amnesty" means
In the UK context, "connection amnesty" refers to a period during which a project holding a grid connection agreement can withdraw from the queue without incurring the cancellation charges that would otherwise apply. Ordinarily, withdrawing from a contracted connection position triggers financial penalties, which creates an incentive for developers to hold positions even on non-viable projects rather than release them.
An amnesty removes that financial barrier, giving developers a penalty-free window to surrender positions they no longer intend to use. The effect is to release the network capacity those positions were holding, making it available to new or more viable applicants.
The term is used both for the specific formal amnesty run by National Grid ESO at transmission level (window from autumn 2022 to April 2023, with processing into 2024) and informally to describe the effect of the broader TMO4+ reform, which achieved similar ends through a structural overhaul of the queue rather than a voluntary surrender window.
The formal TEC amnesty: results
National Grid ESO ran a formal Transmission Entry Capacity (TEC) amnesty that opened in October 2022 and closed in April 2023, with the withdrawal process for participating projects extending into 2024. Projects that expressed interest in leaving the queue during the initial window and supplied the required cost information were permitted to withdraw without cancellation fees.
Around 8 GW of capacity across roughly 50 generation projects expressed interest in withdrawing during the amnesty window (reNews, 2024). Industry commentary later suggested the volume actually removed may have been closer to half that, as some interested projects did not ultimately exit.
In the context of a queue that had grown to hundreds of gigawatts, this was a modest intervention, but it established the principle that penalty-free withdrawal was a legitimate tool for clearing the queue, and it informed the design of the more comprehensive TMO4+ reform that followed.
The TMO4+ reform: the bigger queue clear
The Target Model Option 4+ (TMO4+) reform is the structural response to a queue that the formal amnesty alone could not clear. Approved by Ofgem in April 2025 and live from 10 June 2025, it replaced the previous "first come, first served" framework with a "first ready, first connected" approach (Ofgem, 2025).
Under TMO4+, all projects in the queue underwent a Gate 2 readiness assessment. Projects that could demonstrate planning consent, land rights, and credible progress were designated as "protected" and retained their place in the reformed queue. Projects that could not were assigned to "Gate 1" status, effectively removing them from the active pipeline without their holding capacity any longer blocking viable projects behind them.
The results, published by NESO on 8 December 2025, were significant (NESO, 2025):
- Pre-reform queue: over 770 GW (transmission and distribution combined, including demand connections)
- Projects removed to Gate 1: approximately 217 GW
- Protected pipeline (generation and storage): 283 GW
- Of which prioritised for Clean Power 2030 (Phase 1): 132 GW
- Of which needed by 2035 (Phase 2): 151 GW
- Transmission demand connections protected: approximately 99 GW
Tracker: where capacity is being freed
Last updated: June 2026. This section is updated quarterly as new connection data and Gate 2 offer results become available.
By technology
The protected 283 GW pipeline is dominated by battery storage (83 GW protected, representing a significant overshoot of around 60 GW against system targets), with solar and onshore wind making up most of the remainder (NESO, 2025):
| Technology | Phase 1 (by 2030) | Phase 2 (by 2035) | Notes |
|---|---|---|---|
| Solar | ~30 GW | ~30 GW | Undersupply in most zones; oversupply in some northern and south-western zones |
| Onshore wind | ~12 GW | ~5 GW | Oversupply in Scotland; undersupply in England and Wales |
| Battery storage | ~83 GW combined | Overshoots 2030 target by ~60 GW |
By geography
NESO published a detailed results databook alongside the December 2025 announcement, providing zone-level capacity allocations. The headline patterns from published summaries are (NESO, 2025):
Solar is undersupplied against targets in most distribution zones, meaning substations in most of England, Wales, and Scotland have headroom for additional protected solar projects connecting by 2030. Northern England, South Wales and the Severn area, and South West England show some Phase 2 oversupply, which may indicate that additional projects in those zones face longer waits for firm connection dates.
Onshore wind is oversupplied in Scottish zones (more projects have protection than the zone targets suggest are needed by 2030) and undersupplied across England and Wales, where grid reinforcement is the primary constraint rather than queue length.
Battery storage is structurally oversupplied across most zones given the volume of protected projects. Projects that did not achieve Gate 2 protection in battery-heavy zones may face significant delays even after queue clearing.
At distribution level
The distribution-level queue is managed separately from the transmission queue. As of June 2025, around 145 GW of generation and storage remained contracted at distribution level, based on ENA connections data (Savills, 2025). The TMO4+ process is working through distribution projects on a rolling basis, with the following offer timeline for 2026:
- Gate 2 offers for protected distribution projects with 2026 or 2027 connection dates: due by end of Q1 2026
- Phase 1 distribution Gate 2 offers (all 2030 pathway projects): being issued between July and November 2026 Developers with projects at distribution level should not assume that non-protected status means permanent exclusion. Projects that did not qualify for Gate 2 protection may still connect under non-firm or flexible arrangements, or may qualify in future review windows if their readiness improves.
Connection milestone removals (ongoing)
In parallel with the formal TMO4+ process, all distribution network operators continue to use the ENA Connection Milestones framework to remove stalled projects from the distribution queue on a rolling basis. Projects that miss contractual milestones (for planning consent, land rights, construction commencement, or other agreed deadlines) can be removed by the DNO without a formal amnesty window (ENA Queue Management, 2025).
The ENA publishes aggregated queue data quarterly. Developers can track the distribution queue size and removal rates via the ENA connections data dashboard.
What freed capacity means for new applicants
The practical effect of both the formal amnesty and the TMO4+ reform is that a 'zombie' grid project (a stalled or non-viable scheme holding a queue position) no longer blocks a new applicant at the same substation. Where a substation appeared fully committed on an older heat map because of a long queue of contracted but non-progressing projects, that picture may have changed materially since December 2025.
This does not mean that all previously constrained substations are now open. Physical network constraints (thermal limits, voltage issues, fault level problems) remain. Substations in areas of genuine network scarcity still require reinforcement or flexible connection arrangements regardless of queue length. The difference is that the queue itself is no longer an artificial additional layer of constraint on top of the physical one.
Developers screening sites in 2026 should treat older constraint data with caution. A site dismissed in 2024 or early 2025 because of a heavily committed substation may now have a viable connection path. A current DNO heat map check, ideally alongside a query of the live NESO or ENA connections data, gives a more accurate picture than any static assessment from before the reform.
How to track the queue yourself
NESO connections reform dashboard: NESO maintains a live dashboard tracking the Gate 2 to Whole Queue (G2TWQ) process, showing connections data at 1 MVA and above at both transmission and distribution levels. Updated as Gate 2 offers are issued and accepted. Available at neso.energy/industry-information/connections-reform.
ENA connections data: The Energy Networks Association publishes a collated index of connection data from all distribution network operators, including queue size and status by network area. Updated quarterly. Available at energynetworks.org/industry/connecting-to-the-networks/connections-data.
Individual DNO portals: Each of the six DNO groups publishes its own connection queue data, heat maps, and capacity signals. Data formats and update frequencies vary. NGED, UK Power Networks, SP Energy Networks, SSEN, ENWL, and Northern Powergrid each maintain dedicated connections pages.
Feasibly: Feasibly aggregates live DNO capacity and constraint data alongside planning and geospatial datasets and makes all of it accessible via natural language, removing the need to check six portals individually. A query about a specific site or substation returns current constraint status in minutes rather than days.
Conclusion
The UK's grid connection queue has undergone the most significant structural change in its history over the past two years. The combination of the formal TEC amnesty (which cleared around 8 GW at transmission level) and the TMO4+ reform (which removed 217 GW from the active pipeline) has substantially reduced the artificial queue constraint that was blocking viable projects across Great Britain.
The effect is still working through the system in 2026, as Gate 2 offers are issued and accepted, and as distribution-level projects receive their revised connection dates. Developers and community energy groups screening sites now should treat the queue picture as dynamic rather than fixed, and should verify constraint data against sources updated after December 2025 before making go or no-go decisions on sites that appeared blocked.
This tracker will be updated quarterly as new ENA connection data and NESO Gate 2 offer results become available.