How an Electricity Project Gets a Grid Connection

Where the connections queue stands after Gate 2

The Gate 2 detailed results that NESO published in December 2025 are the first end-to-end picture of the reformed queue.¹³ Across generation and storage, 283 gigawatts have been progressed to firm offers; across demand connections, 99 gigawatts. The portfolio is sorted into two phases. Phase 1 covers projects that NESO and Ofgem judge are needed and able to energise by 2030 to meet the Clean Power 2030 target. Phase 2 covers projects that are needed but on a 2035 horizon. Offer windows run from March 2026 to November 2026 in sequenced tranches by technology and connection voltage, and the next application window opens in the second half of 2026.

That is a different world from eighteen months earlier. The Ofgem Connections Reform decision of April 2025 retired the legacy first come, first served model, and NESO then published three methodologies in quick succession: the Connections Network Design Methodology, the Gate 2 Criteria Methodology, and the Gate 2 to Whole Queue process.⁷ A project that lodged an application in 2022 used to receive an indicative date set only by its position in the contracted-queue order, often a date in the late 2030s. A project lodging now is assessed against eight criteria and, if it qualifies, receives a firm Phase 1 or Phase 2 date. Projects that did not progress through the Gate 2 to Whole Queue assessment have moved to a withdrawal track, returning the capacity their offers had locked against the network model.

Two further moves shape the connection route. The Ofgem connections end-to-end review, with next steps published in December 2025, looks beyond the queue mechanics at the whole connection experience: faster processes, clearer connection data, and connection service standards that hold network operators to defined response times.¹⁴ Those service standards are expected to be carried into the next distribution price control: Ofgem's RIIO-ED3 methodology, the price control proposed for 2028 to 2033, is consulting on connection service standards and output incentives for the network operators, and the detail remains minded-to rather than settled while the consultation runs.¹⁶ The Long Term Development Statement Stage 2 publication of 29 May 2026, under Ofgem's derogation letter of 13 May 2026, sets out the distribution assets and the headroom the queue is being placed against.¹

The journey from first enquiry to energisation

A project moves through seven stages from its first enquiry to the day it is switched on. The first stage belongs to the developer; the middle stages belong to NESO, which screens, places and scores the project; the later stages are the firm offer, the build, and the final switch-on. Each stage names who owns the next step and the rough time it takes. The two off-ramps matter as much as the main path: a legacy project that no longer fits the plan leaves through the orderly withdrawal route, and a project that cannot get firm capacity yet can take a flexible connection that accepts curtailment in exchange for an earlier date.

1. 1
   Initial enquiry and application

   The developer applies to NESO for a transmission connection at 132 kilovolts and above, or to the host distribution network operator for a smaller connection. The application names the site, the voltage and capacity wanted, the technology and the export profile, with early evidence against the eight criteria.

   Month 0 · the applicant
2. 2
   TM04+ readiness and data screen

   NESO checks the application against a baseline of data quality and project readiness. The screen is deliberately light: it sets aside applications that are not credible yet so the detailed assessment can focus on those that are. A project set aside is told which test it fell short on and invited back.

   Month 0 to 2 · NESO
3. 3
   Placement on the network design map

   NESO places the project on the Connections Network Design Methodology zonal map, against the Strategic Spatial Energy Plan and the Centralised Strategic Network Plan. This is where a marginal site is often made strong by a small change: shifting the connection point, or co-locating storage to absorb the voltage rise.

   Month 2 to 4 · NESO
4. 4
   Assessment against the eight Gate 2 criteria

   NESO scores the project against the eight criteria in the Gate 2 Criteria Methodology and produces a composite ranking with a phase recommendation: Phase 1 for 2030 delivery, Phase 2 for 2035, or a referral back with named evidence gaps. The scoring is documented criterion by criterion.

   Month 4 to 6 · NESO
5. 5
   Firm connection offer

   The firm offer is a Bilateral Connection Agreement naming the connection point, the voltage, the entry capacity, the energisation date, the milestone schedule and the charges. The applicant has two months to accept; an offer not accepted in the window lapses and the project returns to a later application window.

   Month 6 to 8 · NESO and the applicant
6. 6
   Construction against milestones

   The project builds under the agreement's milestone schedule, reporting at fixed intervals (typically 6, 12 and 24 months). The milestone tests catch a slipping project while there is still time to recover; missing two in a row triggers a cure-or-terminate notice with a short cure period.

   2 to 4 years for most generation and storage · the applicant
7. 7
   Energisation and switch-on

   The project proves it meets the technical rules, under the Grid Code for transmission or the Distribution Code and the ENA connection recommendations for distribution, and receives its Final Operational Notification.³⁴ It then operates under its capacity right, recorded in the public register that NESO updates each week.

   Phase 1 by 2030, Phase 2 by 2035 · the applicant and NESO

The two off-ramps sit beside this path. A legacy project that no longer fits the strategic plan leaves through the Gate 2 to Whole Queue withdrawal route, which returns its locked capacity to the model for projects that can use it. A project that cannot be given firm capacity at its chosen point, because the local network has no headroom yet, can instead take a flexible connection under Active Network Management: it connects sooner but accepts curtailment during the hours when the network is full, in exchange for a lower charge or an earlier date.

The reform chain from April 2025 to April 2026

The reform is a chain of instruments, not a single document. It starts with the Ofgem Connections Reform decision of April 2025, which approved the policy direction and authorised NESO to publish the methodologies that put it into effect.⁷ The decision sits under the Electricity Act 1989 licence regime and the queue-management duty that NESO inherited under Part 5 of the Energy Act 2023.¹¹ It did not change the duty to offer connection terms in section 16 of the Electricity Act; it changed the rules NESO follows when it frames the offer.

The Connections Network Design Methodology (30 April 2025)

The methodology is the spatial and engineering document of the reform. It sets out how NESO designs the network against a firm pipeline rather than against the whole contracted queue, using zonal capacity envelopes aligned to the Strategic Spatial Energy Plan and to the Centralised Strategic Network Plan, the methodology for which Ofgem approved in April 2026.¹² A project lodging after 30 April 2025 is placed against the zonal map and its capacity envelope, not against the older application-date order. Section 18 of the methodology names the eight criteria a project must meet to qualify for Gate 2, which the Gate 2 Criteria Methodology then sets out in full.

The Gate 2 Criteria Methodology

The Gate 2 Criteria Methodology is the procedural document. It defines how NESO assesses an application against the eight criteria, the evidence required for each, and the scoring and pass thresholds. It also sets the cadence of application windows and the offer windows that follow; the first offer window under the reform opened in March 2026 and runs to November 2026, sequenced by technology and voltage. A developer preparing a new application reads this document first, because it states what evidence the team must assemble and on what schedule.

The Gate 2 to Whole Queue process

The Gate 2 to Whole Queue process handles the legacy backlog. By the fourth quarter of 2024 the contracted transmission queue had reached roughly 722 gigawatts. The process applies the same eight criteria to projects lodged before April 2025, sorting which qualify for Phase 1 or Phase 2 and which are retired through an orderly withdrawal of the offer. Retiring those offers returns their locked entry capacity, which is the mechanism that brought the queue down from about 722 gigawatts to the structured 283 gigawatts of generation and storage plus 99 gigawatts of demand.¹³ The duty that holds NESO and the network operators to publishing the network model the reform runs against is Standard Licence Condition 25, which requires the Long Term Development Statement at intervals of no more than seven years; the Stage 2 publication of 29 May 2026 is the most recent step in that cycle.¹⁰

The queue before and after TM04+

Setting the old and new side by side makes the reform easy to read. The headline numbers are stark, but the more important change is in the mechanics. Before the TM04+ reform, the queue ordered applicants by the date their compliant application arrived. A 2 megawatt rooftop solar project sat ahead of a 2 gigawatt offshore wind farm with full development consent if the rooftop application landed first. The position carried a firm date and could be traded by selling the project company, and the date it implied was often more than a decade away even for small, ready, well-sited projects, because it depended on the speculative pipeline ahead of it that had no obligation to build.

After TM04+, the position depends on the readiness of the project against the eight criteria and its fit with the zonal capacity envelope. A ready 2 megawatt project that matches the local demand pattern lands in the same phase as a 2 gigawatt offshore wind farm of comparable readiness; an unready large project is moved to the legacy track and asked to return when the readiness gap is closed. What a developer trades is no longer a position date but a place in the network design, and the firm offer follows from the design rather than from the order of arrival.

The eight Gate 2 criteria from section 18 of the CNDM

Section 18 of the Connections Network Design Methodology is the heart of the reform for a developer reading it for the first time. It names the eight criteria a project must meet to qualify for Gate 2, the evidence each looks for, and how they are weighted. The criteria are broad rather than narrow: they cover land rights, planning, technology, finance, system need, locational fit, deliverability, and a data-quality test. A project that scores strongly across all eight lands in Phase 1 with a 2030 target; a project strong on system need and locational fit but earlier in its land or consent journey lands in Phase 2 with a 2035 target; a project that scores weakly is asked to return when the evidence is in place.

The eight are checked together as a composite ranking. The criteria also interlock: system need ties to the SSEP and Clean Power 2030, locational fit ties to the zonal map and the LTDS Stage 2 model, deliverability ties to the long-lead procurement schedule, and data quality ties to the same model-based exchange the network is being designed against. A team that maps the criteria onto its existing project documents at the start tends to find them straightforward; a team that prepares one criterion at a time tends to discover gaps late in the assessment.

Connections data: what is open, what is protected, and who decides

A reformed queue only works if everyone can see the same picture of where capacity is and where it is full. Connection decisions now rest on data, and that data falls into the three kinds the diagram above sets out. The first kind is open. Each distribution network operator publishes an Embedded Capacity Register, a public list of the generation and storage connected and contracted on its network, and headroom and constraint maps that show where capacity remains. NESO publishes the queue position and phase from the Gate 2 results, so a developer can see what has already been progressed in a given area.¹³ Open data is what lets a developer choose a sensible point to apply before spending money on an application.

The second kind is protected. Detailed protection settings, customer and site details, security and resilience information, and commercially sensitive contract terms are not published, because releasing them would harm a customer, a competitor position, or the security of the network. The judgement about what to open and what to protect follows Data Best Practice and a triage process that weighs five legitimate reasons to restrict access: privacy, security, negative consumer impact, commercial sensitivity, and law or regulation. The default is open; the burden is on the holder to justify keeping something closed.

The third kind sits between the two. The Data Sharing Infrastructure is a governed way for energy organisations to discover and share data that should not be fully public but does need to move between operators, for example the cross-operator planning data that whole-system network design depends on.¹⁵ A holder lists a dataset in a shared catalogue; a user finds it and requests access; the access is granted under set permissions, time-bound and audited. The infrastructure is being delivered by NESO and is governed under Ofgem's decision on the governance of data sharing infrastructure, which sets who can decide what is shared and on what terms.

The tooling that ties this together is co-ordinated through the ENA Open Networks programme, which keeps the registers and the connection-data formats consistent across the fourteen network operators and runs shared tools such as Connect Direct, which helps a developer find which operator and which part of the network to approach.¹⁷ The Ofgem connections end-to-end review is the policy push behind all of this: among its next steps is a commitment to make more of the queue, the headroom and the connection-status picture open and timely, so that the data a developer relies on to choose a connection point is as current as the model NESO designs against.¹⁴ Holding the network operators to that, through connection service standards now and through the proposed RIIO-ED3 incentives later, is how the data side of the reform is meant to be enforced.¹⁶

Worked example: a 100 megawatt battery through the queue

To make the assessment concrete, the example below walks a hypothetical 100 megawatt, two-hour battery from first enquiry to energisation. The site is in the East Midlands, near a 132 kilovolt substation with documented historic capacity to absorb storage exports during low-demand periods. The developer has three other batteries already operational in the Midlands. The figures are illustrative and the suppliers anonymised, but the steps and timescales match what a comparable project would face in the second-half-2026 application window.

How the queue connects to voltage, network and markets

The connections queue is one of three interlocking subjects a developer or planner reads together. The other two are the voltage and headroom limit the project must live inside, and the market revenue that pays for the project once it is built. Each is kept on its own page so the detail on one does not crowd out the others.

Connections and voltage: the rise limit that decides whether an offer can be firm

Locational fit, criterion 6 of the eight, is where the voltage limit does its work. A connection that exports at a substation where the local voltage is already near the top of the operating range cannot be firmed without one of three remedies: a smaller connection, a flexible connection that curtails during high-voltage hours, or a wait for the reinforcement that brings new headroom.⁵⁶ The voltage page sets out the per-unit arithmetic and a worked voltage-rise example; the journey above is where that estimate becomes a Phase 1, Phase 2 or referral-back decision.

Connections and network: the geography the queue is designed against

The placement step uses the network picture the Centralised Strategic Network Plan and the LTDS Stage 2 publication describe. The network page sets out the asset register, the regional layout and the planned reinforcements coming through the CSNP cycle. A developer who reads the network page first gets a sense of where headroom is and where it is closing, which is exactly what the placement step then tests.

Connections and markets: the revenue that underwrites construction

A project with a firm Phase 1 offer still has to finance the build. The markets page sets out the revenue stack: the Capacity Market for capacity, the wholesale market for energy, and the Balancing Mechanism for ancillary services. The T-4 auction for 2029/30 cleared 40.1 gigawatts at 27.10 pounds per kilowatt against a 39.4 gigawatt target, which gives a Phase 1 project a parallel revenue anchor as its connection offer comes through.⁸ The flexible-connection off-ramp is also a markets mechanism: a project that accepts curtailment in exchange for an earlier date is paid for the output it forgoes, priced through the operator's flexibility tender.