Methods / source ledger
What the numbers mean.
Live data, published statistics and model outputs are different kinds of evidence. This page explains how each is handled and where the dashboard stops making claims.
Core rule
A missing live value is shown as unavailable, never converted to zero. Forecasts and proxies are labelled where they appear.
What updates automatically
The 60-second briefing is generated from the latest successful feeds; its wording changes when the underlying thresholds change.
| Dataset | Refresh | Source |
|---|---|---|
| Balancing prices and accepted actions | 5 minutes | Elexon |
| National demand | 15 minutes | NESO |
| Carbon intensity and generation mix | 30 minutes | Carbon Intensity API |
| Recent capture-rate proxy | 30 minutes | Elexon + NESO |
| BM Unit reference register | 6 hours | Elexon |
| Gas and power forward settlements | 1 hour | EEX |
C&I 2030 prototype
A decision aid built from illustrative business archetypes, not a tariff quote or price forecast.
What the controls change
Choosing an example site changes the archetype. Annual consumption scales its cost components linearly. Contracted share and contract end drive only the exposure panel. Low, base and high are sensitivities around the example.
What is not modelled yet
Postcode, network region, meter data, load shape, supplier contract, exemptions and site constraints are not applied. Flexibility values exclude capex and are illustrative potential, so none of these figures should drive procurement or investment decisions.
Capture-rate proxy
A useful current indicator, deliberately narrower than generator revenue.
output-weighted price
÷ average market-index price
× 100
The dashboard aligns half-hourly Elexon Market Index Data with Elexon metered wind and NESO embedded wind and solar estimates. It uses the latest seven complete dates shared by all sources.
It does not include imbalance exposure, curtailment, subsidies, Contracts for Difference, power-purchase agreements or trading fees. It is therefore described as a market-index proxy, not the price a generator actually received.
Battery identification
Names from the register replace the previous guessed list of unit codes.
What is matched
The Elexon BM Unit register is searched for battery, BESS and energy-storage names. National Grid and Elexon identifiers then join those units to the latest accepted actions.
What the total is not
A BM Unit is not necessarily a unique site, and non-BM batteries are absent. Registered capacity is therefore a visible subset of the fleet, not a GB market total.
Published statistics and models
These update when their publishers release new editions, not continuously.
Solar
DESNZ deployment series through May 2026. The latest months are provisional and combine several administrative sources.
Domestic batteries
MCS-certified UK retrofit installations through March 2026. Commercial, new-build and non-MCS systems are outside scope.
Heat pumps
UK retrofit hydronic systems up to 45 kW through Q1 2026. New-build and non-domestic systems are outside scope.
Bills and forward capture
electricitybills.uk / Ben James model assumptions. These are forecasts in real 2025 pounds, not live tariffs or guarantees.
Forward prices
Settlement prices for future delivery. A settlement is not a forecast and not a quote.
1 therm = 0.0293071 MWh
£/MWh = pence per therm ÷ 2.93071
clean spark spread
= power − (gas ÷ efficiency)
− (0.184 ÷ efficiency × UKA)
Prices come from the public market-data endpoint behind EEX’s own website widgets. It publishes one end-of-day settlement per contract, stamped around 19:00 UTC, so the page refetches hourly and dates itself from the exchange’s trade date rather than from the clock.
The clean spark spread is the only calculated number. It assumes a 50% efficient gas plant and 0.184 tonnes of CO₂ per thermal MWh of gas. Both are assumptions about a notional plant, not measurements of a real one. Where no UK Allowance contract has settled for the month, the carbon term is shown as absent rather than as zero.
GB power on EEX is thin, and some longer-dated GB contracts have no open interest, meaning the exchange quoted the settlement rather than deriving it from trades. Open interest is shown next to every price so this is visible. ICE Futures Europe is the liquidity benchmark for UK gas and UK baseload power, so these figures are described as EEX settlements, never as the UK forward price.
Requests to the exchange are capped at five at a time with one retry, because firing every contract at once gets a share of them refused. Where contracts are missing, the page says how many returned a price rather than presenting a shorter curve as though it were complete.
Primary sources
The shortest path from the dashboard back to the underlying publishers.