The United Kingdom has launched a transformative initiative in its clean energy transition with the approval of the TMO4+ connection reforms, marking the end of the long-criticised first-come, first-served grid connection model. For years, this outdated system allowed speculative projects to occupy capacity, creating a bottleneck that stalled genuine, shovel-ready renewable developments.
With a backlog of approximately 756 GW—more than five times the UK’s peak electricity demand—the need for reform was undeniable. The new framework is designed to fast-track viable wind, solar, and battery storage (BESS) projects, but while it promises efficiency, it also introduces complex legal and financial challenges.
“The removal of the first-come, first-served system creates uncertainty for projects already in the queue that lack readiness, such as land rights or planning consents,” explains Harshita Khurana, Senior Energy Lawyer in the UK, to Strategic Energy Europe. Developers must now reassess contractual assumptions, manage shifting risk allocations, and prepare for potential renegotiations if they fail to meet the newly established readiness criteria.
Legal risks behind efficiency gains
A key component of TMO4+ is the elimination of “zombie projects”, which, while beneficial for grid efficiency, raises concerns over developer losses. “It could expose developers to sunk cost losses, particularly where no fault-based termination mechanisms exist,” warns Khurana.
She anticipates a wave of legal scrutiny focusing on procedural fairness, transparency, and the potential breach of legitimate expectations under existing agreements.
Moreover, the reordering of the queue—while necessary to prioritise projects with planning consent and realistic timelines—may lead to claims from developers feeling disadvantaged by retroactive changes.
“Seamless implementation will be key to realising this vision,” Khurana stresses, noting that legal advisors are playing a critical role in helping clients navigate this evolving landscape and identify opportunities amidst regulatory uncertainty.
A £40 billion bet on grid modernisation
Central to the success of TMO4+ is the UK’s commitment of 40 billion pounds to upgrade its grid infrastructure. This investment aims to create a more agile and responsive network capable of supporting the country’s ambitious renewable energy targets.
The reforms introduce clear timelines: evidence windows for transmission and distribution will open in May and July 2025, revised offers will begin in Autumn 2025, and priority will be given to projects connecting between 2026 and 2027. All connection offers up to 2030 are set to be addressed under the new criteria, ensuring long-term clarity for developers.
Additionally, the current pause on new applications—implemented in January 2025—will be lifted once TMO4+ is fully operational, with all pending applications assessed under the revised framework.
Investor focus and supply chain implications
For investors, grid access has now become a premium asset. “Investors will zero in on projects with secured or near-term grid connections, as power availability directly impacts valuations and project economics,” says Khurana.
This shift is likely to fuel the emergence of secondary markets where grid connection rights are traded, adding a new dynamic to renewable project financing.
The acceleration of grid connections will also place immediate pressure on the global supply chain for renewable technologies. With heightened demand for solar panels, wind turbines, and BESS components, manufacturers will be challenged to scale production rapidly. Khurana notes, “While short-term supply constraints are expected, the long-term outlook points to increased manufacturing investment and regional supply chain resilience.”
A global trend with local nuances
The UK’s reforms align with international efforts to streamline grid access. In Australia, similar reforms tie grid priority to financial readiness, while Germany adopts a technology-specific approach through tailored auctions. “The UK’s strategy is broader and bolder, focusing on overall viability rather than specific technologies,” Khurana observes.
This proactive stance could inspire other European nations to adopt comparable measures, especially as they seek to meet the EU’s Green Deal objectives. The UK, despite its departure from the EU, positions itself as a leader in regulatory innovation for renewable energy integration.
Khurana welcomes Ofgem’s approval of these groundbreaking reforms but remains cautious: “Reordering the queue may raise fairness concerns and lead to legal challenges, but it also offers a significant opportunity for more equitable access.”
As the sector adapts, legal advisors will be essential in guiding developers and investors through compliance complexities and unlocking the potential of this bold reform.
“We’re closely monitoring how this shift unfolds, supporting clients to navigate compliance and seize the opportunities it presents,” Khurana concludes.
