UK government demands no more connection offer delays, mulls BESS oversupply options

Further delays to grid connection offers in the United Kingdom will not be accepted, according to an open letter to the energy industry from the UK government. New measures to tackle continued oversupply of BESS are also being considered, with proposals including a new fee for oversubscribed technologies.

The overhaul of Great Britain’s connections queue has faced significant delays in a process that has frustrated developers and sparked a reaction from the Department of Energy Security and Net Zero (DESNZ).

In the letter signed by DESNZ and regulator Ofgem, the government described the ongoing connections reform process as critical to achieving clean power deployment targets. DESNZ claimed data errors in historic connection agreements had contributed to significant delays, but warned “further slippage is not acceptable,” adding that expectations have been set for a “firm, coordinated response.”

Grid operator NESO started implementing connections reform in late 2025, in response to unsustainable growth in Great Britain’s connections queue – a tenfold increase over a five-year period resulted in a queue of more than 700 GW of generation and energy storage projects, with some shovel-ready projects facing a 10-year wait to connect.

NESO updated its connections methodology, switching from a first-come, first-served basis to a system based on project readiness. The process followed multiple rounds of industry consultation and was successful in removing 221 GW of projects from the queue, including 153 GW of BESS.

Projects remaining in the queue are now prioritized based on new readiness criteria, such as securing planning consent and land rights, with shovel-ready projects assigned a “Gate 2” offer – the faster stream for grid connections.

Despite reform, the Gate 2 offer process has faced delays, and there remains a significant oversupply of eligible BESS projects. The government’s open letter described the high volume of battery storage projects advancing to Gate 2 relative to 2030 deployment targets as an “emerging risk.”

The UK government wants to see 23 GW to 27 GW of deployed grid-scale BESS capacity by 2030. Connections reform may have succeeded in removing a high volume of non-viable projects, but there remains 14.8 GW more BESS capacity in the queue than is needed for the 2030 target, and 61.7 GW more than the projected battery system need in 2035.

There are multiple factors behind this, according to the government, including measures in the new connection methodology that protect projects with planning consent, capacity market agreements, or near-term connection expectations. These protections in combination with the speed at which a BESS project can typically secure planning consent compared to other types of installation has led to more batteries securing Gate 2 status than was expected, according to the government.

Options are now under consideration to tackle the oversupply, although the government also expects a level of attrition as projects drop out of the queue for normal market competition reasons.

Industry proposals that have been brought forward include introducing a “commitment fee” for oversubscribed technologies – such as BESS – relative to the government’s 2030 targets. The CMP470 modification to Great Britain’s grid connection code was proposed in March 2026 by developer Field and has been subject to industry debate.

Other proposals floated by industry include introducing an amnesty for developers who wish to reconfigure their existing Gate 2 application without losing queue position, and a mechanism allowing developers to trade surrendered capacity for earlier connection dates on stronger assets.

DESNZ said that as a first step, it has been engaging with networking companies on practical mitigations, such as expanding the use of shared grid connections (known as bay-sharing in Britain), and it remains “supportive of steps that can help manage the effects of the surplus while maintaining a fair and efficient process.”

While affected by delays, new connection offers are being distributed. NESO confirmed on April 8 that around 88% of the total Gate 2 protected offers had been issued, with the remaining in the final stages of processing. Distribution network operators have also begun issuing revised offers to customers.

The full open letter to industry can be found on the UK government’s website.