Harmony Energy Income Trust (assets under Foresight Group)
Owns 10 batteries at 9 sites, 398 MW, which is 5 per cent of everything operating in Great Britain. It sells none of that power itself. The register names 3 other companies as the sellers: BP Gas Marketing Limited, Tesla Motors Limited and BGI Trading Limited.
Who sells its power
The balancing mechanism register names the company allowed to sell each unit's power. That company is usually an optimiser or a supplier working under contract, which is why the registers cannot answer the ownership question on their own. Where the seller is one of the owner's own companies, the row says so.
| Seller | Batteries | MW | Of this fleet |
|---|---|---|---|
| BP Gas Marketing Limited | 4 | 183 | 46% |
| Tesla Motors Limited | 5 | 180 | 45% |
| BGI Trading Limited | 1 | 35 | 9% |
What it was paid
The three published lines, added up across the fleet for the 364 days to 16 October 2026. Wholesale trading income is invisible for every owner, not just this one, and nothing here nets the cost of charging. The rate is per kilowatt of current capacity.
| Balancing mechanism, paid to discharge | £23.7m |
| Balancing mechanism, paid out to charge | −£19.4m |
| Response and reserve auctions | £5.4m |
| Capacity market | £3.4m |
| Income across the fleet, per kilowatt | £81.87/kW/yr fleet 46.47 |
| Median battery, all three lines | £88.17/kW/yr |
| Hours at full power, sent out | 495 h/yr |
| Hours at full power, taken in | 602 h/yr |
What the fleet is made of
Duration, by megawatt
Region, by megawatt
Every battery it owns
| Battery | MW | Sold by | Grade | £/kW/yr |
|---|---|---|---|---|
| Little Raith BESS Stirlingshire and Fife | 50 | Tesla Motors Limited | probable | 43.32 |
| Pillswood 2 Battery Storage South Lancashire, Yorkshire and Humber | 50 | BP Gas Marketing Limited | probable | 98.39 |
| Pillswood 1 Battery Storage South Lancashire, Yorkshire and Humber | 50 | BP Gas Marketing Limited | probable | 98.21 |
| Hawthorn Pit BESS North East England | 50 | BP Gas Marketing Limited | probable | 74.79 |
| Ilmer Lane BESS Oxfordshire, Surrey and Sussex | 50 | Tesla Motors Limited | probable | 87.74 |
| Thame Road BESS Oxfordshire, Surrey and Sussex | 50 | Tesla Motors Limited | confirmed | 62.13 |
| Rusholme South Lancashire, Yorkshire and Humber | 35 | BGI Trading Limited | probable | 88.70 |
| Wormald Green BESS South Lancashire, Yorkshire and Humber | 33 | BP Gas Marketing Limited | probable | 113.69 |
| Farnham BESS Oxfordshire, Surrey and Sussex | 20 | Tesla Motors Limited | probable | 88.17 |
| Broadditch Battery Essex and Kent | 11 | Tesla Motors Limited | probable | 73.96 |
How we know
Confirmed means a control filing at Companies House, or the owner's own published statement, names the company. Probable means the evidence is strong and indirect. Named means the register leaves the owner blank, the balancing code carries the owner's initials, and a sibling unit at the same site is already settled. Each chain below is printed once, with the batteries it settles.
Confirmed Thame Road BESS
The register names no owner. The capacity market holds a site called Bumpers belonging to HEIT Holdings Ltd 890 metres away, and Harmony Energy's own community fund announcement names Bumpers as one of the three sites the trust owns. Source
Probable Little Raith BESS, Pillswood 2 Battery Storage, Pillswood 1 Battery Storage, Hawthorn Pit BESS, Ilmer Lane BESS, Rusholme, Wormald Green BESS, Farnham BESS, Broadditch Battery
The HEIT SPV naming; the trust sold its assets to Foresight. Source
Attribution. A battery belongs to whoever the documents name today, so a fleet that changed hands during the year credits the whole year to the current owner. Groups are joined only where a filing joins them; a company that holds through several vehicles appears once, under the name at the top of the chain. Directors and registered offices are never used as evidence on their own. Why the registers cannot answer this question