Swangate
49 MW, about 98 MWh (2 hours, 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 27 September 2026, or is labelled as an estimate.
What it is
| Registered power | 49 MW response and reserve auction registration |
| Storage duration | 2 hours capacity market de-rating class |
| Charging zone | North Midlands and North Wales |
| Connection site | Rotherham |
| Postcode | S63 6AG |
| Balancing mechanism unit | none found under the codes we search |
Who owns it and who trades it
| Traded by | BGI Trading Limitedruns several sitesconfirmed, Elexon's register |
| Owned by | SWANGATE ENERGY STORAGE LIMITED |
| Owner established from | capacity market registered holder |
| Ultimately | Econergy confirmed source |
How we know. The control filing gives Swangate Energy Storage Limited to Econergy International Limited at three quarters or more with the right to appoint directors, since December 2021. Yoogen 1 LLP and Rockhaus Ltd held it before that. The capacity market points elsewhere, holding a Low Carbon site 570 metres away, which is why the filing rather than the neighbour decides it.
Market registers name the party that sells into the market, which for a battery is usually an optimiser under contract rather than the owner. Elexon's balancing mechanism unit register names the seller here and the name is checked against it on every build. How we tell them apart
What it is built from
| Battery system | Trina Storage, Elementa LFP (supply and EPC) |
| Engineering and construction | Trina Storage with G2 Energy (delivery consortium) |
| Entered operation | early 2024 (expected at announcement) |
From published documents, not from any register: supplier and contractor project pages, owner announcements and the trade press. Confidence: confirmed. Checked 2026-08-30. source 1. Fields not shown are not published anywhere we have found, and we do not guess them.
What it earned
| Line | 364 days to 27 September 2026 |
|---|---|
| Balancing mechanism | not published |
| Response and reserve auctions auction implied | £216k |
| Capacity market | £249k |
| Three lines together | £465k |
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 the cleared price raised for inflation where the auction set a base period, split by month on EMRS's weights. Method
Outside the balancing mechanism, derived from the meter
Elexon publishes what this unit's meter recorded every half hour. Take away the balancing volumes NESO accepted and what is left is the position the unit ran outside the balancing mechanism: its wholesale trading, its frequency response delivery, and its losses, together. This unit held a frequency response contract in 2,518 of those half hours. The energy the contract asked of it, contracted megawatts times NESO's published delivery curve at the measured grid frequency, is taken out of the position and valued at the imbalance price, because it sits outside the unit's declared position and that is the price Elexon settles it at. What remains is the traded position, valued at the market index. In 2 half hours a contract was held but the grid frequency is not yet held, so those are left in the traded position. The volumes are measured. The prices are public benchmarks, not this unit's trades. The product is derived, and is shown apart from the three measured lines above. 346 days to 12 September 2026, 33 of them still provisional in Elexon's settlement runs. Method and caveats
| Line | MWh or £ |
|---|---|
| Metered export, what crossed the meter out | 24,097 MWh |
| Metered import, what crossed the meter in | 26,687 MWh |
| Equivalent full cycles, everything sent out over one full charge | 246 over 346 days, 259 a year at that rate |
| Apparent meter to meter efficiency | 90%, an ordinary battery: round trip losses alone |
| Balancing offers accepted | 0 MWh |
| Balancing bids accepted | 0 MWh |
| Position outside balancing, export | 24,097 MWh |
| Position outside balancing, import | 26,687 MWh |
| Of which expected response delivery, net | −2,389 MWh 1,954 out, 4,343 in |
| Traded position, net | −202 MWh 24,601 out, 24,803 in |
| Traded position at the market index, sold | £2.3m |
| Traded position at the market index, bought | £1.9m |
| Traded position, net, at the index | £403k |
| Response delivery, net, at the imbalance price | −£238k −£220k at the index |
| Balancing and outside balancing together | £165k £3.55/kW/yr |
When it moved, against when power was dear
Across every half hour this unit was metered the market index averaged £93.43. What it sent out was worth £91.90 a megawatt hour at that same index, 0.98 times the average. What it took in was worth £74.89, 0.80 times. Selling above one and buying below one is a unit positioned into the dear half hours and out of the cheap ones. It measures the half hours it chose, not the price anyone paid it, which is not published.
Physical checks passed: the meter never exceeded the registered power by more than fifteen per cent, and the year's exports against imports are what a battery does.
Where it stands
| All three measured lineswhole fleet, £/kW/yr | 21st percentile229 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 |
|---|---|---|---|
| Melksham East | 49 | 2h | £107.3/kW/yr |
| York | 49 | 2h | £53.0/kW/yr |
| Melksham West | 49 | 2h | £37.3/kW/yr |
| Ilmer Lane BESS | 50 | 2h | £35.7/kW/yr |
| SSE Salisbury | 49 | 2h | £24.9/kW/yr |
| Swangatethis battery | 49 | 2h | £9.5/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.