Why does CMP470 make sense?
Ofgem’s minded-to consultation on CMP470 closes on Thursday 1 October. It proposes an Oversubscribed Technologies Commitment Fee, a charge on battery storage projects for holding a queue position in a technology the system already has too much of. I’ve submitted a response supporting it. This piece sets out why, and what I’ve suggested alongside it. Read the full piece
The problem in two numbers
Around 90 GW of battery storage is either operating or holds Gate 2 status: roughly 7 GW of the first and 83 GW of the second. Estimated need by 2035 is around 29 GW. Some surplus is useful, because projects drop out and others need to be ready to replace them. Three times the requirement is well past that point, and network companies still have to plan for all of it.
Holding a place has cost very little. Ofgem’s impact assessment shows that 26% of the battery capacity at Gate 2 or already energised has posted no securities or liabilities at all. Counted by project, half have posted less than £800/MW in securities. Projects commissioning in 2027, where Ofgem presumes the full user commitment regime already applies, have posted £5,600/MW on average. At the low end, a queue position is close to free.
Why the fee works
The fee starts at £3,000/MW. If the oversubscription doesn’t fall, it rises to £5,000/MW after six months and then by £5,000/MW every six months to a ceiling of £25,000/MW. None of that bites straight away: the fee first appears in the July 2027 securities statement and is payable from October 2027.
Ofgem puts the ceiling at more than 25% of build cost for a short-duration battery and more than 7% for a four-hour one. The £3,000/MW start is 12% of the ceiling, which on the same basis works out at roughly 3% and under 1%. A developer who intends to build can carry that. One holding a position as an option has a reason to think again, and plenty of notice to do it.
That’s the job a commitment fee does. Ofgem has no direct read on whether a developer means to build, so the fee asks for money and lets the answer sort the queue.
Seeing who holds the queue
The impact assessment looks at the response to the fee mainly as a choice between staying and leaving. There’s a third option, which is to sell.
A developer that would rather not fund a rising security can sell the project company to someone better placed to. The capacity stays in the queue and the new owner posts the fee. Ofgem has seen the pressure coming. Stakeholders told it that stronger fees fall hardest on smaller, less well-capitalised developers, and the impact assessment accepts that a liquidity requirement may favour larger balance sheets. What neither document goes on to consider is a change of ownership.
Ofgem prices the interest cost of the fee at a single real rate of 4.08%, taken from BBB-rated utility bonds, and applies it to every developer. The index behind that rate only admits bonds rated BBB- or better. A smaller developer without an investment-grade rating is likely to borrow above it, so its cost may be somewhat higher than the headline figure suggests.
Changes of ownership are already hard to see, whatever the reason for them. In July 2026 Alpiq bought 90% of Harmony Energy, with co-founder Peter Kavanagh keeping 10% and staying on as chief executive; brand, team and operating model all carried over. On 9 July, as the deal completed, Companies House stopped naming anyone as controlling the company. Kavanagh’s 10% sits below the reporting threshold, and the company filed a statement that it has no registrable person or registrable legal entity. The TEC Register lists project companies and carries no ownership field, so nothing on it records the change. There’s nothing to suggest the sale had anything to do with the fee, which isn’t active yet. It’s simply an example of how little a change of control shows up.
Exits can be just as hard to read. Between the register snapshots of 14 and 25 August 2026, seven projects totalling 4.2 GW left the TEC Register. All seven sit in companies of one joint venture between Elmya Energy and Renewable Power Capital. At Companies House, the seven and a related development company were all reorganised on the same day, 31 March 2026, with identical changes of registered office, directors and company secretary. Nothing was filed around the August exit, and the companies remain active. Anyone reading the register line by line would log seven separate exits; it takes the company names, and a look at Companies House, to see a single owner’s decision behind them.
Gate 2 status is also now a deal term. In May, Gresham House agreed to buy a 480 MW battery project near Rayleigh, conditional on the project receiving a favourable Gate 2 offer.
None of this counts against the fee. If a project passes to an owner who can post the security and build it, the queue is better used for it. Ofgem concludes that competition effects are likely to be limited, and that may well prove right. Ownership data would allow it to be tested, and would show changes in the structure of the battery pipeline that the register on its own can’t.
The data centre door
The impact assessment notes that some battery projects are trying to modify their Gate 2 offers to connect as data centres instead, citing up to 9 GW. Demand is outside the fee, so conversion looks like a way out. NESO’s guidance closes most of it. A full change from battery storage to a data centre is treated with a later queue position, because a data centre imports at close to full load for far more hours. Converting costs the place in the queue.
Two things are still unclear: what happens to fee already posted when a project converts, and how a converting project sits against the separate commitment fee proposed for data centres under Curate. I’ve asked Ofgem to confirm both.
What would help
I’ve suggested two things, both modest. NESO could collect the ultimate controlling party of each fee-liable project when securities statements are issued, starting with the first one in July 2027. It needn’t be published project by project. An aggregate figure, such as the share of liable capacity held by the largest owners, would do. Then a review after the first two escalations, comparing ownership at activation with ownership at review and setting exits against sales.
With that data in hand, Ofgem could track who ends up holding the queue once the fee starts to bite.
If the fee works and the queue shrinks, how would anyone know whether the capacity that remains is held by more owners or fewer?
Sources
Ofgem, CMP470 minded-to consultation, September 2026 (paras 2.5, 3.18, 3.23, 3.24, 5.13, 5.14)
NESO, Guidance on Material Technology Changes (section 4.1)
Fasken, Harmony Energy completes sale of a majority stake to Alpiq, July 2026
Companies House, Harmony Energy Limited (10141078), persons with significant control
Companies House, RPC Elmya Carnation company filings
NESO TEC Register, snapshots of 14 and 25 August 2026
Energy-Storage.news, UK BESS M&A rebounds, 9 June 2026 (Gresham House, Rayleigh)