The UK’s electricity grid is undergoing a significant transformation. With the Government’s Clean Power 2030 target in sight, reforming how energy projects connect to the grid is now a national priority.
In April 2025, Ofgem approved the Target Model Option 4 (TMO4+) package of reforms, marking a major shift in how grid access is managed. TMO4+ aims to reduce delays, prioritise projects that are ‘ready’, and support the transition to net zero.
At the heart of the reform is a move away from the traditional "first come, first connected" process which has resulted in delays due to ‘zombie projects’ (essentially projects that are in the queue but are not ready for connection, and may not be progressing at all). Instead, the new model led by the National Energy System Operator (NESO) prioritises projects that are first ready and needed, shifting to a "first ready, first connected" process. This means developers must demonstrate that the project meets defined readiness criteria to secure a connection offer. For most projects this will include planning consent, land rights and strategic alignment with national energy goals (amongst other criteria).
Ofgem’s role
Ofgem is actively working with NESO to ensure the reform delivers a strong and fair outcome, specifically, that connection offers are issued correctly and reflect a project’s readiness and strategic value rather than timing alone.
A key update from Ofgem’s October blog is its role in handling disputes. While NESO and Distribution Network Operators (DNOs) will manage most complaints through their own procedures, Ofgem will step in where complaints cannot be resolved through these channels. This provides an important safeguard for developers and reinforces the regulator’s commitment to fairness.
Ofgem is also reviewing its determinations policy and plans to consult on dedicated guidance for disputes arising from the reform. Notably, it has clarified that it will not revisit the core TMO4+ decisions but will focus on cases where procedural fairness is in question. It is also considering a cost recovery mechanism for handling determination requests, an important detail for developers to factor into their planning.
Implications for stakeholders
For developers, the message is clear: securing a grid connection now requires more than early registration. Legal teams will need to ensure that planning permissions, land agreements and funding structures are robust and well-documented. The reforms introduce new milestones and governance requirements that demand careful management.
Local authorities and infrastructure planners should also take note. NESO’s roadmap encourages closer coordination with planning bodies, creating opportunities to fast-track clean energy projects that support regional growth and decarbonisation.
Looking ahead
Ofgem’s active involvement in implementation and dispute resolution adds a layer of confidence to the reform process. By supporting a fair and strategic queue formation, the regulator is helping to unlock billions in private investment and accelerate the delivery of clean energy infrastructure.
Mills & Reeve advise clients across the energy, infrastructure and public sectors on how to navigate these changes. Whether you’re seeking grid access, assessing project viability or responding to new regulatory obligations, early engagement and strategic planning will be key.
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