The UK government has set a clean power goal of generating at least 95 per cent of Great Britain’s electricity production from clean sources by 2030. This is necessary to accelerate to a net zero UK economy by 2050. To achieve this, it launched the Clean Power 2030 Action Plan (CPAP) in December 2024 to harbinger a new era of clean energy independence and a secure and affordable supply, by sprinting to a low-cost, domestically powered electricity system. This is driven by the UK’s desire to reduce its dependence on gas imports for electricity generation and heating (given its recent vulnerability to the unstable global energy prices in the wake of the Russia-Ukraine conflict), reduce greenhouse gas emissions, and create essential new energy industries (that will create more jobs and drive economic growth). It builds on the National Energy System Operator’s (NESO) Clean Power 2030 (CP2030) report, which outlines a path toward a cleaner, more resilient energy market, urging the government to prioritise speed over perfection and working together with the industry to meet the 2030 target.

Achieving this goal means focusing on fully harnessing domestic energy resources, cutting reliance on imported fossil fuels, and accelerating clean power to support the growing demand for electric vehicles, low-carbon heating, industrial electrification, and clean hydrogen. The CPAP defines the actions to be taken to accelerate the delivery of clean energy projects, electricity market reforms, strong supply chains, and new approaches to building grids. A flexible energy system, on both the supply and demand sides, will be essential to keep the system balanced and costs down. With a clear view of the future energy mix till 2030 and 2035, the UK government has clearly articulated that the fundamental reform of the connections process is critical and urgent, and without it, the projects needed to achieve CP2030 goals will not connect on time.

To address this, in April 2025, the UK’s energy regulator, Office of Gas and Electricity Markets (Ofgem), made changes to the regulatory framework to implement connection reforms, specifically by approving NESO’s Target Model Option 4 (TMO4+) connection reform package. This includes industry code modifications, connections methodologies established under the NESO licence (as amended), and Electricity Standard Licence Condition changes (introduced by Ofgem). Subsequently, in the same month, NESO published the final versions of the connection methodologies – Gate 2 Criteria, Connections Network Design Methodology (CNDM) and Project Designation (explained later). These contain minor amendments following Ofgem’s recommendations and will be used to implement the connection reforms.

These reforms seek to address long wait times of over 15 years and slow connection rates, which are misaligned with the system’s needs. In fact, the capacity waiting in the queue [756 GW as of January 2025, with renewable energy (350 GW) and storage (262 GW) dominating the queue] represents four times the capacity needed by 2030 and twice that needed by 2050. These challenges are resulting in inefficient network planning and weakening investor confidence, which will be addressed by the proposed reforms.

This article presents the key highlights of the CPAP and the TMO4+ reform package…

Clean Power 2030 Action Plan – key highlights

Great Britain (which encompasses England, Scotland and Wales) faces the considerable challenge of increasing the share of clean energy production to 95 per cent from over 60 per cent in 2024. This will be exacerbated by the need to accelerate overall supply to meet the electricity demand, which is expected to increase by around 11 per cent by 2030. This requires significant expansion in offshore wind (OSW), onshore wind, solar, and battery energy storage systems (BESS) to replace retiring plants and meet rising demand.

Under the Department for Energy Security and Net Zero (DESNZ) 2030 ‘Clean Power Capacity Range’, by 2030, the government aims to deploy 43-50 GW of OSW, 27-29 GW of onshore wind and 45-47 GW of solar to be complemented by a flexible capacity of 23-27 GW of BESS and 4-6 GW of long duration energy storage (LDES) as well as the development of flexibility technologies including gas carbon capture utilisation and storage, hydrogen, and substantial opportunity for consumer-led or demand flexibility. Further, the security of supply will be protected with the maintenance of 35 GW of unabated gas reserve capacity, which will be used only when needed.

In line with the NESO advice, the government has acknowledged that the planned new capacity must be underpinned by the rapid delivery of 80 network-and-enabling-infrastructure projects (excluding eight additional works which would be beneficial if accelerated), most of which are already at an advanced stage of planning and development. Of the total projects, nine have already been built, 68 are on track, and three require acceleration to meet timelines. The maturity of these projects varies across the development cycle: four projects are in Stage 1, (scoping), 24 are in Stage 2 (strategic optioneering), 16 are in Stage 3 (design, development, and consenting), 10 are in Stage 4 (planning and consenting), and 17 are in Stage 5 (construction). Three critical projects, which currently have delivery dates beyond 2030, are located in East Anglia and the southeast and are vital for connecting OSW in the North Sea and enabling the flow of clean power. Without these projects, the clean power target is expected to fall short by about 1.6 per cent in 2030, and consumers could incur an additional GBP4.2 billion in constraint costs.

The UK’s clean energy system will see once-in-a-generation levels of energy investment – an estimated GBP40 billion on average per year between 2025-2030, with GBP30 billion for generation assets and GBP10 billion for grid infrastructure being required to achieve the CPAP. Some of the key actions outlined in the CPAP, to be taken to accelerate delivery, are discussed here briefly.

The first and most significant among them are the electricity networks and connections reforms, for which Ofgem has been working with the transmission owners (TOs) and distribution network operators (DNOs) to prioritise projects needed for 2030, while maintaining a robust pipeline beyond 2030. The CPAP connections reform annex provides a detailed breakdown of the CPAP pathway and capacity ranges to help align NESO-led connection reform process with CP2030. This includes Great Britain-level capacity ranges for 2030, in line with the government’s 2030 pathway and technology capacity till 2035. These are mainly derived from NESO’s net zero-aligned Future Energy Scenarios (FES) 2024. NESO is expected to use the top-end of the government’s 2030 pathway (DESNZ Clean Power Capacity Range) to underpin connection offers for projects in and before 2030, and 2035 FES-derived ranges to underpin connection offers till 2035. Notably, these FES-derived ranges do not constitute a government pathway but an established public basis to provide longer-term certainty on connections, ahead of the Strategic Spatial Energy Plan (SSEP), due to be published in 2026.

NESO has estimated in its CP2030 that around twice as much new transmission network infrastructure will be needed in the nation’s grid by 2030 as has been built in the past decade. This would require regulatory reforms to ensure investments can be made ahead of need, and time taken to build networks can be reduced. This includes DESNZ working with Ofgem to explore the appropriateness of tightening the incentives and penalties on TOs and DNOs to drive accelerated network delivery. The Scottish and Welsh governments are also considering how their planning and consenting regimes would integrate with CP2030. The key idea is that with a prioritised grid queue, planning and consenting processes for key clean power projects can be speeded up across Britain. Then, the system can prioritise 2030-critical projects.

To aid this, DESNZ has brought onshore wind back into the Nationally Significant Infrastructure Project (NSIP) regime. DESNZ has brought forward a Planning and Infrastructure Bill with measures to streamline the delivery of critical infrastructure in the planning process, and convene community, nature, and industry groups on complex projects to stress-test them prior to application. In line with Lord Banner’s recommendations after a review of legal challenges to NSIPs in October 2024, the UK government is working on reforms to expedite major infrastructure projects. The government is also committed to ensuring that a reformed planning system enhances nature restoration by delivering the Marine Recovery Fund for Offshore Wind, besides considering strategic mitigation approaches for onshore infrastructure in England. The UK government and the Scottish government are working together to establish a similar Marine Recovery Fund for projects in Scotland in addition to reforms to deliver a streamlined and efficient legislative framework for infrastructure consenting. In Wales, the Infrastructure (Wales) Act 2024 sets out the new consenting process for significant infrastructure projects, replacing multiple consenting processes in Wales with a single process.

To accelerate delivery of clean energy, the government plans to address specific issues related to the contracts for difference (CfD) allocation process for renewable energy and implement a package of targeted reforms particularly for OSW, which will play a role as the backbone of the clean power system. The latter includes a better budget for fixed-bottom OSW, an auction schedule to improve predictability, and review of auction parameters. Separately, the plan is to leverage Great British Energy (set up by the UK government in July 2024 to drive up clean energy) and wider policy measures to support local and community-led renewable capacity, including for homes, businesses, public buildings and land, and shared spaces. The UK government is also committed to nuclear power, while recognising the Scottish government’s policy of supporting new nuclear developments in Scotland.

Market reforms are equally essential to ensure that the market works in tandem with support schemes to deliver the right investment and operational signals, and that sector-specific barriers to deployment are addressed. The Review of Electricity Market Arrangements (REMA) programme is considering the reforms needed to ensure that the market arrangements remain fit for the renewables-dominated power system of the future. The policy development phase of this programme will conclude in mid-2025.

To deal with the intermittency of renewable energy sources, a Low Carbon Flexibility Roadmap will be published in 2026, with new actions to drive clean power flexibility by 2030. New market reforms will also be introduced to provide batteries and demand flexibility with appropriate and fair access to relevant markets, and there will be consultation on how grid-scale batteries could be referenced in future planning reforms, and on including grid-scale batteries within the environmental permitting regulations.

To build a strong domestic supply chain, the upcoming Industrial Strategy will include a sector plan for clean energy industries. Further, the Clean Industry Bonus (increased recently from an initial GBP200 million to GBP544 million for the upcoming seventh round of the CfD scheme) will support manufacturing in coastal and energy communities, and cleaner, more sustainable supply chains. Further, the UK’s sovereign wealth fund, National Wealth Fund (NWF), will focus at least GBP5.8 billion of its capital on green hydrogen, carbon capture, ports, gigafactories, and green steel while Great British Energy will support the growth of clean power supply chains around the UK.

The UK government will establish a Clean Power 2030 Unit to monitor the delivery of the key 2030 projects. This unit will work closely with those involved in practical delivery, including the devolved governments (particularly the Scottish and Welsh governments), to cut through issues quickly and to build a comprehensive view of the power infrastructure currently in development.

TMO4+ connection reform package: Key highlights

Ofgem decision package

The TMO4+ reform package replaces the “first come, first served” basis with the “first ready and needed, first connected” principle. The approved Ofgem’s decision package includes the Connection and User System Code (CUSC) modifications CMP434 (new projects) and CMP435 (existing projects), along with the modification of the System Operator-Transmission Owner Code (STC) CM095 to enable the CMP434 implementation. Next, it includes the three connection methodologies:

  • The Gate 2 Criteria methodology outlines the criteria for prioritising new and existing projects seeking to connect to the transmission system, making a new Gate 2 queue of prioritised projects.
  • CNDM outlines the process that NESO and network companies will follow to establish the new Gate 2 queue, assess the enabling infrastructure required to make connections, design a coordinated network and prepare connection offers.
  • The Project Designation methodology contains the process for enabling the connection of projects that are critical to the security of supply; are critical to system operation; materially reduce system/network constraints; and are highly innovative or have particularly long lead times. Effectively, these are projects that can deliver significant net zero, system or consumer benefits.

Finally, Ofgem has made changes to the licences of NESO and transmission and distribution operators to implement the new TM04+ proposals. It also published the impact assessment of the effects of the proposed changes across different areas.

The “gated” connection process 

The package enables a new gated connection process that reforms the existing queue to prioritise those projects that are ready and needed (that is, meet the readiness and strategic alignment criteria respectively) under the CPAP, in a firm connections queue with Gate 2 offers (with confirmed connection date and location). Further, it deprioritises those that do not meet the criteria to an indicative Gate 1 with offers for transmission connections only, with an indicative connection date and point. These projects can, however, reapply in the future once they meet the criteria to be able to move to Gate 2. This process applies to new projects as well, which have to meet both readiness and strategic alignment criteria to be able to join the Gate 2 connection queue.

The three key features of this approach are viability, need and efficiency. The Gate 2 queue comprises projects that are demonstrably viable and progressed – having land rights or sufficiently progressed their planning status and those that best meet the current and future system need, in alignment with CPAP or any other strategic alignment criteria set by the government. The mix of ready and needed projects is maintained as projects that drop out will be replaced by others with the same technology.

TMO4+ will apply to all transmission-connected projects and certain distribution-connected schemes that have a material impact on the transmission system and qualify for the transmission impact assessment (TIA). Notably, the threshold for TIA is currently fixed at 200 kW in Scotland and 1 MW in England and Wales, with a live code modification CMP446 seeking to increase the threshold to 5 MW. Demand-side connections are automatically deemed needed, but must show project readiness to progress. However, smaller generation and storage projects and all demand projects connecting at the distribution are out of scope. Certain “protected” or “significantly progressed” projects in the existing queue will be prioritised for Gate 2 connection offers. These include schemes scheduled to connect in 2026 or 2027 while the evidence of significantly progressed covers projects with planning consent; holders of contracts for difference (CfDs); holders of capacity market agreements; long-duration electricity storage, interconnector or offshore hybrid asset (OHA) cap and floor agreement or merchant interconnector approval; and live contract with NESO awarded through their network services’ processes. These projects will retain their current connection rights. Others will be reassessed under the new framework, issued varied connection contracts, and required to reapply once they meet Gate 2 criteria. Separately, DNOs will implement a process replicating TMO4+ at the distribution level for new and existing projects.

Expected outcomes for existing projects

The TMO4+ reforms are expected to result in around 296 GW (medium scenario of three scenarios considered and includes 123 GW of already built capacity) of confirmed connection queue (Gate 2) that is largely aligned with the CPAP capacities up to 2035, but potentially with some technologies under-supplied. Particularly, Ofgem anticipates an undersupply of onshore wind (10 GW), OSW (22 GW), low carbon dispatchable technologies (19 GW) and interconnectors (2 GW) compared to the CPAP 2035 permitted capacities, and solar (4 GW) when applying the amalgamated permitted capacities.

Further, an estimated 482 GW of projects are expected to receive Gate 1 offers. This includes an estimated 360 GW of projects that do not meet the readiness criteria and 122 GW of projects that do meet the readiness criteria but do not meet strategic alignment criteria. The latter are predominantly battery storage projects and some solar projects in specific geographical locations. The assessment further estimates that the overall funds spent by developers of projects that will receive a Gate 1 offer could be around GBP1-GBP3 billion. Further, there is 42 GW of demand in the queue (17 GW at the transmission level and 25 GW at the distribution level), including projects such as large industrial demand and data centres. The transmission level projects are deemed needed, as already mentioned, and hence would only have to demonstrate readiness to receive a Gate 2 offer.

The next steps

Ofgem has identified the following implementation timeline for the TMO4+ reform, with all 2030 Gate 2 offers to be issued by early 2026.

  • May 2025: Gate 2 evidence window opens for distribution-connected customers.
  • June 10, 2025: Commencement of the new process following a standstill period of 56 days to allow for relevant licence changes, followed by a notice period of four weeks as required by the new CUSC requirements.
  • July 2025: Gate 2 evidence window opens for transmission-connected customers.
  • September 2025: NESO to confirm Gate 2 outcomes and prioritised queue positions.
  • Autumn 2025: Issuance of revised connection offers, starting with 2026-27 projects.
  • Late 2025: New application window opens for future projects under the TMO4+ framework.

The way forward

Given that the opening of application windows to create Gate 2 is very close, project developers that have existing agreements and wish to enter Gate 2 must begin preparations to submit evidence to show their projects meet the readiness criteria. To support developers in this task, on April 11, 2025, NESO published three updates – a draft of the Readiness Declaration template, updated guidance for letters of authority (LOA) (to show that the land for their projects meets minimum acreage requirements), and updated information on queue management guidelines. NESO is expected to release further guidance and host webinars to help developers with the new connection process.

Overall, the reforms will prioritise projects and businesses in the UK that can deliver clean energy at affordable prices (in line with CPAP-permitted capacities for 2030 and 2035 and enable the realisation of net zero by 2050), drive growth and provide energy security.