Vitreous LabsEnergy transparency

Harmony Energy Income Trust (assets under Foresight Group)

Owns 11 batteries at 10 sites, 474 MW, which is 6.1 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.

11batteries, counting a re-registered battery once
474 MWof the 7,779 MW operating fleet
£64/kW/yrpaid across the three measured lines, against £42 for the whole fleet
2 of 11confirmed on a control filing or the owner's own statement, the rest 9 probable

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.

BP Gas Marketing Limited 259 MW · Tesla Motors Limited 180 MW · BGI Trading Limited 35 MW
SellerBatteriesMWOf this fleet
BP Gas Marketing Limited525955%
Tesla Motors Limited518038%
BGI Trading Limited1357%

What it was paid

The three published lines, added up across the fleet for the 364 days to 27 September 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£20.9m
Balancing mechanism, paid out to charge−£16.6m
Response and reserve auctions£6.2m
Capacity market£3.4m
Income across the fleet, per kilowatt£64.47/kW/yr fleet 42.17
Median battery, all three lines£76.88/kW/yr
Hours at full power, sent out485 h/yr
Hours at full power, taken in584 h/yr

What the fleet is made of

Duration, by megawatt

2 hours and up 415 MW · not published 59 MW

Region, by megawatt

Scotland 50 MW · England and Wales 424 MW

Every battery it owns

BatteryMWSold byGrade£/kW/yr
Hawthorn Pit BESS
North East England
60BP Gas Marketing Limitedprobable40.11
County Durham (FBPG02)
North East England
59BP Gas Marketing Limitedconfirmed23.82
Little Raith BESS
Stirlingshire and Fife
50Tesla Motors Limitedprobable44.47
Pillswood 2 Battery Storage
South Lancashire, Yorkshire and Humber
50BP Gas Marketing Limitedprobable98.35
Pillswood 1 Battery Storage
South Lancashire, Yorkshire and Humber
50BP Gas Marketing Limitedprobable98.53
Ilmer Lane BESS
Oxfordshire, Surrey and Sussex
50Tesla Motors Limitedprobable85.90
Thame Road BESS
Oxfordshire, Surrey and Sussex
50Tesla Motors Limitedconfirmed65.19
Wormald Green BESS
South Lancashire, Yorkshire and Humber
40BP Gas Marketing Limitedprobable93.47
Rusholme
South Lancashire, Yorkshire and Humber
35BGI Trading Limitedprobable20.51
Farnham BESS
Oxfordshire, Surrey and Sussex
20Tesla Motors Limitedprobable95.14
Broadditch Battery
Essex and Kent
11Tesla Motors Limitedprobable76.88

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 County Durham (FBPG02)
The register names no owner. The capacity market holds Hawthorn Pit BESS belonging to HEIT Holdings Ltd 720 metres away, and the site already carries another unit confirmed to the trust. Source

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 Hawthorn Pit BESS, Little Raith BESS, Pillswood 2 Battery Storage, Pillswood 1 Battery Storage, Ilmer Lane BESS, Wormald Green BESS, Rusholme, 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

All owners