Tesla Motors Limited
Sells into the markets for 15 units at 13 sites, 541 MW together, over the 364 days to 27 September 2026. Everything here is measured from published settlement and auction results; wholesale trading is invisible for every optimiser, not just this one. Elexon's balancing mechanism register names it on every one of them.
The book
| Balancing mechanism, paid to discharge | £25.8m |
| Balancing mechanism, paid out to charge | −£25.4m |
| Response and reserve auctions | £5.3m |
| Capacity market | £5.1m |
| Income across the book, per kilowatt | £67.02/kW/yr fleet 42.17 |
| Median unit, all three lines | £76.74/kW/yr |
| Hours at full power, sent out | 419 h/yr |
| Hours at full power, taken in | 660 h/yr |
What the book is made of
Performance follows portfolio shape as much as skill: a Scottish, long duration book does a different job from an English one hour book, so the mix belongs beside the money, not in a footnote.
Duration, by megawatt
Region, by megawatt
Whose batteries it sells
None of the book is its own. The 4 owners behind it are established from control filings, on the owner pages. A battery that re-registered under a new code is counted once.
| Owner | Batteries | MW |
|---|---|---|
| Harmony Energy Income Trust (assets under Foresight Group) | 5 | 180 |
| TagEnergy | 5 | 169 |
| FRV (Abdul Latif Jameel) | 4 | 142 |
| Amber Energy | 1 | 50 |
Every unit it sells for
| Unit | MW | Balancing | Standing ready | CM | £/kW/yr |
|---|---|---|---|---|---|
| Chapel Farm BESS Mid Wales and The Midlands | 50 | £3.3m | £637k | £562k | 89.21 |
| Little Raith BESS Stirlingshire and Fife | 50 | £934k | £721k | £562k | 44.47 |
| Roaring Hill BESS Stirlingshire and Fife | 50 | £1.1m | £355k | £518k | 38.56 |
| Skelmersdale Battery South Lancashire, Yorkshire and Humber | 50 | £3.1m | £473k | £232k | 76.74 |
| Ilmer Lane BESS Oxfordshire, Surrey and Sussex | 50 | £3.3m | £403k | £509k | 85.90 |
| Thame Road BESS Oxfordshire, Surrey and Sussex | 50 | £3.0m | £215k | — | 65.19 |
| Clay Tye Farm 2 Battery Storage Essex and Kent | 50 | £2.8m | £628k | £1.1m | 90.87 |
| Clay Tye Farm 1 Battery Storage Essex and Kent | 50 | £2.6m | £544k | — | 63.17 |
| Contego Battery Oxfordshire, Surrey and Sussex | 36 | £1.2m | £527k | £372k | 58.40 |
| Jamesfield 1 Battery Storage Eastern Grampian and Tayside | 30 | £300k | £300k | £556k | 38.64 |
| Farnham BESS Oxfordshire, Surrey and Sussex | 20 | £1.5m | £140k | £219k | 95.14 |
| Hawkers Hill Battery Somerset and Wessex | 20 | £1.4m | — | £227k | 82.29 |
| Jamesfield 2 Battery Storage Eastern Grampian and Tayside | 19 | £208k | £239k | — | 23.59 |
| Broadditch Battery Essex and Kent | 11 | £663k | £60k | £120k | 76.88 |
| Holes Bay Battery Somerset and Wessex | 7 | £411k | £79k | £113k | 85.16 |
What the documents say
The register names who sells; these are the arrangements behind that, from owner and optimiser announcements, each with its kind, because an optimisation agreement, a route to market, a toll, a floor and self-trading are different products with different risk.
| Site | MW | Party and arrangement |
|---|---|---|
| Clay Tye | 99 | Tesla (Autobidder), optimisation, seller and optimiser the same, from 2023 confirmed source |
Attribution. A unit belongs to whoever the market registers as its seller today, so a book that changed hands mid year credits the whole year to the current seller. The exception is a battery that re-registered under a new code: it is counted once, under the code it runs on today, and where the earlier code sold through somebody else that seller keeps what it earned. We have recorded optimiser switches since 27 August 2026 and the record deepens from here. Corporate families are not joined: a platform selling through several registered entities appears as several rows on the optimiser list.