Britain's battery queue is becoming a capital test

Ofgem's proposed Oversubscribed Technologies Commitment Fee (OTCF) would introduce a minimum financial commitment for projects in technologies whose connection queue materially exceeds the government's capacity target. For battery energy storage systems, the immediate commercial implication is clear: a Gate 2 position should no longer be treated as equivalent to a bankable project or a probable equipment order.

A large queue is not the same as a large addressable market

Ofgem estimates that Britain has approximately 7GW of operational BESS and 83GW with Gate 2 status, compared with a Clean Power 2030 requirement of 23–27GW by 2030 and a Future Energy Scenarios-derived requirement of 24–29GW by 2035. The regulator's concern is not simply that some projects will fail. It is that they may exit too late, after networks have planned around connection positions that do not become operating assets. Ofgem's consultation remains open until 1 October 2026.

Britain still needs substantially more storage. The government's July 2026 Clean Flexibility Roadmap reports that grid-scale battery capacity reached 7.5GW at the end of 2025, after a record 2.3GW was energised during that year. The policy problem is therefore not “too many batteries” in operation; it is too many connection claims relative to the projects the system is likely to need and finance.

The proposed fee changes liquidity before it changes capex

Under Ofgem's minded-to position, the OTCF would activate when a technology's contracted capacity exceeds its target requirement by more than 50%. It would start at £3,000/MW, rise to £5,000/MW after six months if still active, and then increase by £5,000/MW every six months to a maximum of £25,000/MW. It would switch off once oversubscription falls below 25%. The full design is set out in the CMP470 minded-to consultation.

For illustration, a 100MW project would face a minimum security floor of £300,000 initially and £2.5 million at the maximum level. That is not necessarily an equivalent increase in project expenditure: projects already posting security above the floor would be unaffected, and Ofgem says the OTCF would be returned when a project energises. The nearer-term effect is therefore on liquidity, guarantee capacity and portfolio prioritisation.

This distinction matters. A well-capitalised developer may retain several projects while a smaller developer concentrates resources on one. A project with planning consent, credible land rights, a defined connection programme and an investable revenue case is better placed to justify the commitment. A project held mainly for optionality becomes more expensive to keep alive.

Why Asian suppliers should care

China accounts for more than 80% of global lithium-ion battery manufacturing capacity, while Chinese, Korean and Japanese producers supply nearly all battery cells used worldwide, according to the IEA's Global EV Outlook 2026. Asian manufacturers are therefore central to the UK supply chain, even when a project developer, investor or EPC contractor is British or European.

The commercial risk is that equipment suppliers mistake the connection queue for future procurement demand. If CMP470 accelerates attrition, some prospective orders may disappear earlier — but the remaining pipeline should become more credible. Suppliers should value that improvement. A smaller set of financeable projects can be more commercially useful than a larger set of speculative enquiries.

The response should not be to offer indiscriminate vendor financing or weaker terms. Instead, suppliers should qualify counterparties more rigorously. Before allocating engineering time, pricing support or warranty capacity, they should ask for evidence of Gate 2 terms, existing cancellation securities, planning status, land control, energisation milestones, revenue assumptions, financing strategy and the treatment of any co-located generation.

Bankability will extend beyond the connection agreement

The proposed fee is only one part of the credibility test. Developers still need a viable route through planning, safety, insurance, procurement, construction and market participation. The UK Health and Safety Executive's BESS guidance highlights legal responsibilities covering worker and public safety, fire and explosion risk, electrical safety and notification obligations. Those requirements affect technology selection, system design, warranties, emergency planning and the evidence expected by lenders and insurers.

For manufacturers entering Britain, a competitive data room should therefore go beyond cell price and cycle life. It should include independently supportable performance assumptions, degradation methodology, fire-safety architecture, certification, warranty exclusions, augmentation strategy, cybersecurity controls, spare-parts arrangements and a credible UK service model. Local execution capability becomes part of the product.

Co-location deserves separate attention. Ofgem's original proposal contains a targeted exemption for certain projects where the oversubscribed technology connects after another technology, does not increase Transmission Entry Capacity and requires less than £250,000 of additional attributable works and connection costs. The final treatment is not yet settled, so solar-plus-storage developers should not assume exemption without checking the detailed conditions.

What decision-makers should do now

Developers should run a project-by-project liquidity test at £3,000, £5,000 and £25,000 per MW, while recognising any existing security already above those floors. Investors and lenders should separate connection status from delivery probability and ask which milestones create the next cash or security requirement. Equipment suppliers should rank opportunities by evidence of execution rather than headline megawatts.

For Asian market entrants, the strategic opportunity remains attractive but narrower than the queue suggests. The winning proposition is unlikely to be “lowest-cost battery hardware” alone. It is a bankable package combining technology, documentation, safety, service and credible counterparties.

Ofgem has not made a final decision, and alternative designs remain under consideration. But the direction of travel is already informative: Britain wants storage projects that are not merely connected on paper, but capable of carrying the financial and operational obligations required to reach energisation.

Methodology and caveat

This commentary is based on public information available on 27 September 2026. CMP470 is a consultation, not a final rule; fee levels, exemptions and implementation may change. Illustrative calculations are simple applications of the proposed £/MW floors and do not model financing costs, existing securities or project-specific contractual terms. This is general market commentary, not legal, financial, tax or investment advice.