Holes Bay Battery
7 MW in Somerset and Wessex. Everything on this page is read from published data for the 364 days to 19 August 2026, or is labelled as an estimate.
What it is
| Registered power | 7 MW balancing mechanism registration |
| Storage duration | 2.0 hours capacity market de-rating class |
| Charging zone | Somerset and Wessex |
| Connection site | Holes Bay, Poole |
| Postcode | BH15 |
| Balancing mechanism unit | E_BHOLB-1 |
Who owns it and who trades it
| Traded by | Tesla Motors Limitedruns several sites |
| Owned by | HARMONY HB LIMITED |
| Owner established from | capacity market registered holder |
Market registers name the party that sells into the market, which for a battery is usually an optimiser under contract rather than the owner. How we tell them apart
What it earned
| Line | 364 days to 19 August 2026 |
|---|---|
| Balancing mechanism | £412k |
| Response and reserve auctions auction implied | £81k |
| Capacity market | £88k |
| Three lines together | £580k |
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
What it might have earned trading, estimated
| At our middle assumption | £114k |
| Across the range | £87k to £140k |
| Energy cycled in the year | 5,183 MWh |
This one is a model, not a measurement. Nobody publishes what any site traded. It is never added to the measured lines. How it is worked out and what is wrong with it
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.