Accelerating Deployment of Renewables in the UK: The Grid Connection Queue⚡
The difference between offered and requested connection date: 59 months.
The UK’s energy transition is at full force while we are approaching the final days of 2024. The nation’s commitment to a low-carbon energy system has led to significant milestones, including the closure of its last coal-fired power station, Ratcliffe-on-Soar. In addition, 2024 is expected to be a historic year, with share of renewables in electricity generation surpassing fossil fuels first time for the full year.
Looking forward, the share of clean power in the UK is expected to increase further with a combination of market forces (i.e., decreasing equipment and installation costs) and policy support. The UK Government’s Clean Power 2030 Action Plan has set ambitious targets for clean energy by 2030 across different technologies as shown below:
One question as to whether we can achieve these ambitious targets is how quickly we can process the so called connection queue - the backlog capacity waiting to connect to the grid at the transmission or distribution level. At its core, the connection queue reflects both the success of the energy transition in driving demand for new projects and the challenges inherent in aligning infrastructure capacity with that demand. Between 2019 - 2023, the applications for connection to the grid have tripled. In order to address the significant growth of the queue, in December 2023, the Energy System Operator (ESO) introduced a new initiative on a “first ready, first connected” approach (also known as TMO4), that prioritises projects that can deliver at speed and avoids ‘zombie projects’ stalling the queue. Earlier this year, the ESO introduced an updated version of this proposal to make the new rules also applicable for existing projects in the queue - while the original one was to cover new applications only from January 2025. With the enactment of this proposal, the ESO expects to halve the connection queue and enable earlier connection dates for viable projects. What is the state of the queue?
The State of the Queue 📊
As of October 2024, the combined connection queue across transmission and distribution networks in the UK has reached 739GW, comprising 698GW of export (i.e. generation) and storage projects and 41GW of demand projects. Renewables dominate the queue, accounting for 47% 🌞, while storage projects represent 34% 🔋. This pipeline far exceeds the energy needs for achieving the UK’s net-zero targets, highlighting the sheer scale of interest in renewable energy and storage development.
However, the scale of the queue brings both opportunities and challenges:
Opportunities: Accelerating the deployment of clean energy to meet decarbonisation goals ✅. However, it is worth caveating that the total new installed capacity to reach net zero by 2050 is estimated at approx. 275 GW.
Challenges: Managing delays in connection timelines and addressing the dependence of distribution connections on transmission reinforcements⚡.
Key Challenges in the Connection Queue 🚧
Connection Delays ⏳
Only 31% of transmission offers in October met requested connection dates, with an average delay of 59 months. These delays are driven by constraints in grid capacity, the complexity of reinforcement works, and overlapping dependencies between distribution and transmission systems.
Dependence on Transmission Reinforcements 🔗
A significant portion (70%) of contracted distribution capacity is dependent on (38%) or being assessed for (32%) transmission reinforcements. This creates a bottleneck, as projects at the distribution level often face delays due to broader grid upgrade requirements.“Zombie Projects” 🧟♂️
A notable issue in queue management is the presence of stalled or inactive “zombie projects.” To address this, network operators have removed 11.4GW of such projects from the queue, helping free up capacity for viable projects. But we know from past experience that, the capacity of projects that will eventually not go ahead is much higher than this.Mismatch Between Capacity and Deployment 📉
While over 53GW of distribution-connected projects and 56GW of transmission-connected projects could potentially connect without delay, actual deployment remains subject to customer timelines, supply chain constraints, and regulatory approvals.
Steps Taken to Accelerate Connections 🚀
The UK’s energy networks and regulatory bodies are actively implementing measures to reduce delays and accelerate project connections:
Connections Action Plan 📅: This initiative has accelerated connections by 10.4GW, cutting six years from connection timelines. Key solutions include offering non-firm interim connections for storage and leveraging technical limits to fast-track approvals.
Capacity Released 🔓: Changes in access rights for storage projects have freed up over 60GW of capacity, allowing for more efficient grid utilization.
Queue Management 🗂️: Robust queue management practices are ensuring that inactive projects are removed, while active projects receive timely updates on connection milestones. They are now adding another “milestone” in the process (Gate #2) to assess the progress more frequently. Those that fail to complete a milestone will be dropped off the queue.
Next Steps
The UK stands at a critical moment in its energy transition. While significant milestones have been achieved, including the closure of coal-fired power plants and a growing share of renewables, the road ahead demands sustained effort, innovation, and collaboration. Achieving the Clean Power 2030 targets and addressing the challenges posed by the connection queue will require concerted efforts across different dimensions. A few ideas are as follows:
Strengthening the grid infrastructure: modernising and reinforcing the grid will reduce the additional works needed for connection of renewables and storage assets
Expand the “first ready, first connected” approach: the success of this initiative will depend on an effective implementation. Regular monitoring (which is interlinked with the next point) is critical to ensure the projects with the highest readiness are connected without delay
Enhance queue transparency: transparent updates for developers on project status and timelines will increase confidence in the system
Address supply chain and workforce constraints: robust supply chain and skilled workforce is a big driver of accelerated deployment of renewables
Incentivise demand-side flexibility: consumer-led flexibility can alleviate pressure on the grid while increasing system resilience. Large-scale adoption of flexibility is driven by a combination of increasing the robustness of the technology (e.g., vehicle-to-grid), supportive market mechanisms (e.g., dynamic pricing) and policy support (e.g., participation in capacity markets).