Welkin Mill
20 MW, about 20 MWh (1 hour, from the capacity market de-rating class) in North Midlands and North Wales. Everything on this page is read from published data for the 364 days to 22 September 2026, or is labelled as an estimate.
What it is
| Registered power | 20 MW response and reserve auction registration |
| Storage duration | 1.0 hours capacity market de-rating class |
| Charging zone | North Midlands and North Wales |
| Connection site | Stockport |
| Postcode | SK6 2BH |
| Balancing mechanism unit | none found under the codes we search |
| Reserve auction codes | EDFE-21 until 9 February 2026; AG-GEDF05 from 10 February 2026 the same battery under a new code, usually a new company trading it; its money here is both codes together |
Who owns it and who trades it
| Traded by | EDF ENERGY CUSTOMERS LIMITEDruns several sitesauction results, unchecked |
| Owned by | EQUINOR WELKIN MILL LIMITED |
| Owner established from | capacity market registered holder |
| Ultimately | Equinor (Noriker Power develops and operates) confirmed source |
How we know. Equinor's own announcements for Blandford Road and Welkin Mill.
Market registers name the party that sells into the market, which for a battery is usually an optimiser under contract rather than the owner. This unit is registered only in the response and reserve auctions, so the seller is the participant NESO's auction results name, and Elexon's register carries no entry to check it against. How we tell them apart
What it earned
| Line | 364 days to 22 September 2026 |
|---|---|
| Balancing mechanism | not published |
| Response and reserve auctions auction implied | £106k |
| Capacity market | £189k |
| Three lines together | £295k |
Balancing is offer revenue and does not net off the cost of the power. The response and reserve figure is the value implied by the published auction results, award quantity times clearing price times the length of the delivery window, and not a settled payment. Capacity market income is at the price the agreement cleared at, before inflation uprating, so it is a floor. Method
Outside the balancing mechanism, estimated from metered peers
Elexon publishes no metered output for this registration, an auction unit rather than a balancing mechanism unit, so nothing can be derived for it. What can be said is what its peers did: 15 units of about 1 hour in England and Wales, metered, earned between £-0.22 and £26.99 per kilowatt a year with the balancing legs and the position outside the balancing mechanism together, £5.99 at the median. Applied to this unit's 20 MW that is £120k, in a range of −£4k to £540k. An estimate from other batteries, never this one's figure. Method
Where it stands
| All three measured lineswhole fleet, £/kW/yr | 31st percentile199 units |
Percentiles, so 90 means better than nine in ten of the cohort named beside it, on that measure alone, over the same 364 days. Rates are pounds per kilowatt per year, annualised over the days the unit has been on the system, the same figures the performance league ranks on. A high position in the taken-in table is not a fault: a constraint asset is paid to charge, and charging is its job.
The nearest comparables
The five nearest in size in England and Wales, and this battery among them, ranked by what each was paid for every kilowatt it holds over the 364 days to the same date. They run for about the same length of time. Same market, same rules, same weather.
| Battery | MW | Hours | Measured, per kW |
|---|---|---|---|
| Willoughby | 20 | 1h | £63.0/kW/yr |
| Gerrards Cross BESS | 20 | 1h | £36.3/kW/yr |
| Ernesettle | 19 | 1h | £16.3/kW/yr |
| Pulse Clean (HAB12-FFR) | 21 | 1h | £15.9/kW/yr |
| Welkin Millthis battery | 20 | 1h | £14.8/kW/yr |
| Pulse Clean (HAB13-FFR) | 21 | 1h | £11.3/kW/yr |
See it on the map
Every figure on this page traces to a published file. If something here is wrong about your asset, the methods section says how to tell us.