Methodology and sources
How the UK AI Energy Index is compiled, classified, reviewed and corrected.
The UK AI Energy Index distinguishes between official figures, calculated figures, industry estimates, AI Energy Intelligence estimates and forecasts. Data-centre electricity consumption is not presented as AI-specific consumption unless reliable evidence supports that distinction.
Methodology version 1.0.
What each sub-index measures
- AI Electricity Demand Index
- Electricity consumed by UK data-centre and AI activity: annual consumption, share of national demand, AI-specific consumption where it can be isolated, quarterly and annual growth, published 2030 and 2035 forecasts, and estimated peak-power requirements.
- Data Centre Growth Index
- Physical infrastructure: operational facilities, facilities under construction, approved and proposed developments, new capacity in megawatts, regional concentration, hyperscale developments, and planning approvals and refusals.
- Grid Pressure Index
- Network capability: connection requests, average connection waiting time, projects delayed by insufficient capacity, available regional capacity, substation and transmission constraints, planned network investment, flexible connection agreements, and the risk of local congestion.
How data is classified
Every value carries one of the following classifications, shown next to the figure itself:
- Official figure — published by the originating organisation and checked against the primary document.
- Calculated from official figures — derived from official figures. The inputs, units, sources and formula are retained with the record, and the figure cannot be published without them.
- Industry estimate — an estimate published by a third party, reproduced with its source.
- AI Energy Intelligence estimate — our own estimate, with the method, assumptions and limitations stated.
- Forecast — a projection of a future period, kept separate from observations.
- Not disclosed — the figure exists but has not been made public.
- Insufficient evidence — the available evidence does not support a defensible figure or rating.
- Data not yet available — no figure has been entered yet. The cell stays empty rather than being filled, and zero is never used in its place.
Estimates and forecasts
Forecasts are never mixed into current observations. On the AI Electricity Demand Index they appear in a separate table, and charts plot only recorded readings for periods that have already occurred. No sub-index carries a headline score until enough sourced readings exist to support one; until then each reads “Baseline in development”.
Preventing duplicate developments
Each development is held once, as a unique record with its own project name, operator, location, status, capacity, planning authority and planning reference. The database enforces a single record per planning authority and reference, so a project reported by several outlets cannot be counted twice. Where a project appears under different names, the earlier record is amended rather than a second one created.
Regional definitions
Both the growth and grid-pressure sub-indices use the same nine regions. Slough and the Thames Valley is separated from the wider South East because of its concentration of existing capacity.
- London
- Slough and the Thames Valley
- South East England
- Midlands
- North West England
- North East and Yorkshire
- Scotland
- Wales
- Northern Ireland
How grid-pressure ratings are assigned
A region receives one of five ratings: Low pressure, Moderate pressure, High pressure, Severe pressure, Insufficient evidence. A rating is only recorded when there is a written explanation and a stated evidence-confidence level. A rating of low, moderate, high or severe cannot be published unless at least two published evidence records are attached to the assessment; the database rejects the attempt and the region stays at “Insufficient evidence”. A rating is never assigned automatically from a single data point. Ratings reflect recorded evidence about connection demand, delays, constraints and planned investment — not opinion, and not the number of projects alone.
Two documents repeating one underlying claim are not independent corroboration. Evidence must concern the same geography and the same assessment period, and network licence areas do not necessarily match these regions: a figure covering a grid supply point or a whole licence area is recorded at that geography and is never treated as a figure for a region. Demand headroom is kept separate from generation headroom, and planned reinforcement is kept separate from capacity already available.
Current limitation. This methodology does not yet define the criteria that separate low, moderate, high and severe pressure. Until those thresholds are published, every region remains at “Insufficient evidence” even where evidence has been collected. Defining them is the next stage of work; we will not invent thresholds or assign ratings to fill the table. Publishing individual national indicators does not complete the rating baseline.
National figures — such as the Great Britain connection queue — describe the country as a whole and are never apportioned to a region or used to justify a regional rating. Northern Ireland is assessed only from Northern Irish sources, as it sits on a separate electricity system. An average connection waiting time is never inferred from individual delayed projects.
Review frequency and corrections
Every indicator carries its own update schedule and a “last reviewed” date, and the index as a whole is reviewed quarterly. Corrections supersede rather than erase: the previous record is retained and the change is logged. To request a correction, use our corrections policy or contact us with the indicator, the figure in question and the source you believe is correct.
Limitations of UK data
There is no single official register of UK data centres, their capacity or their electricity consumption. Operators are not required to disclose site-level load, planning records are held by individual authorities in inconsistent formats, and connection-queue data is published at network rather than facility level. AI-specific consumption is rarely separable from general compute. The index reflects those gaps openly instead of closing them with estimates.
Geographic definitions
Every figure records the geography it covers, because UK, Great Britain and single-nation statistics are not interchangeable. The available coverages are: United Kingdom, Great Britain, England, Scotland, Wales, Northern Ireland, UK region, Local authority, Individual facility, Other. Northern Ireland is assessed separately from Great Britain throughout the Grid Pressure Index.
Confidence ratings
Each figure and each regional assessment carries a confidence rating of High, Medium, Low, Not assessed. Confidence describes the strength of the underlying evidence, not the precision of the number.
Counting projects, campuses and capacity
One record represents one facility or development. Where several buildings share a campus, each building is recorded separately and the campus name links them, so campus capacity is never added to the individual building figures. Totals are reported by development status and are never combined: proposed developments are not added to operational facilities.
Capacity figures always state what they describe: IT load, Total facility load, Grid-connection capacity, Campus capacity, Capacity definition unclear, Not disclosed. IT load, total facility load and grid-connection capacity measure different things and are never treated as equivalent or summed together.
Forecasting rules
Forecasts are recorded against the year they describe, are labelled as forecasts wherever they appear, and are shown in their own table rather than alongside recorded consumption. A chart is only drawn when at least two genuine reporting periods have been entered and approved. We do not extrapolate a trend from a single observation.
Update process
- Sources are checked monthly; the whole index is reviewed quarterly.
- Every record stores the date it was last checked and the date it is next due.
- A replacement value never overwrites history: the earlier reporting period is kept, the superseded figure is marked as such, and the change is logged with who made it, when, why and against which source.
- Superseded sources are retained and marked superseded rather than deleted.
Source categories monitored
The index draws on publications from the organisations below. Listing an organisation does not imply a figure has been taken from it: a source only appears in the register once its document title, URL and publication date have been entered and verified.
- Department for Energy Security and Net Zero
- Department for Science, Innovation and Technology
- National Energy System Operator
- Ofgem
- National Grid Electricity Transmission
- UK Power Networks
- National Grid Electricity Distribution
- Scottish and Southern Electricity Networks
- Electricity North West
- Northern Powergrid
- SP Energy Networks
- SONI
- NIE Networks
- Utility Regulator Northern Ireland
- Local-authority planning portals
- Planning Data service
- House of Commons Library
Change history
dc_project — developer
Applicant/developer is named in published sources but was missing from the record.
Previously: — · Now: Digital Land & Development with Peel Waters
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — developer
Applicant/developer is named in published sources but was missing from the record.
Previously: — · Now: QuestPit Limited
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — developer
Applicant/developer is named in published sources but was missing from the record.
Previously: — · Now: Apatura
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — capacity_mw
Kao Data publishes a 40 MW figure for Kenwood Point without a stated definition. Shown on the profile and excluded from totals.
Previously: — · Now: 40 (definition not published)
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — developer
Applicant/developer is named in published sources but was missing from the record.
Previously: — · Now: Segro and Pure Data Centres Group
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — summary
The government announcement gives 3,450 jobs for the North Wales AI Growth Zone.
Previously: more than 3,400 new jobs · Now: 3,450 jobs
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — summary
The summary cited 213 MW while the record showed 212.42 MW. Both now reflect the range of reported figures; the definition is still unstated.
Previously: 213 MW · Now: 212.42 MW (reported range 210–213 MW)
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — summary
The summary still described an application awaiting a decision, although the record's status is approved. Summary updated to the October 2025 committee approval.
Previously: Hybrid planning application submitted · Now: Approved October 2025
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — stated_electricity_demand_mw
The Hillingdon committee report (2 October 2025) states the development requires 250 MW of power through two National Grid connections. Recorded as stated electrical demand; it is kept separate from IT-load totals.
Previously: — · Now: 250
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — status
Latos Data Centres stated in December 2024 that the Cardiff data centre at Rover Way was under construction (Nation.Cymru).
Previously: approved · Now: under_construction
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — summary
The summary said no capacity was recorded while the record showed 4.3 MW of IT load. The summary now names the operator's specification sheet as the source.
Previously: No electrical capacity is stated, so none is recorded · Now: 4.3 MW IT load explained
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — status
DataVita's c.£300m debt facility (August 2026) funds construction of DV3, and trade press reported it under construction in September 2026. The status now matches the record's own summary.
Previously: approved · Now: under_construction
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — summary
The summary said no capacity was recorded while the record showed 31 MW of IT load. The summary now names Colt's London 4 page as the source.
Previously: states no floorspace or electrical capacity, so none is recorded · Now: 31 MW IT load explained
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — status
Construction of Colt London 4 started in February 2023 (Colt DCS via PR Newswire) and the operator describes it as under construction.
Previously: approved · Now: under_construction
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — summary
The summary said the decision letter gives no capacity figure, but the decision letter and Inspector's Report state 72 MW of IT capacity, which the record already shows. Summary corrected.
Previously: no capacity figure is given · Now: 72 MW IT load explained
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — status
Enabling works and earthworks began in October 2025 and phase 1 reserved matters were approved in December 2025 (BBC; Ridge).
Previously: approved · Now: under_construction
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — summary
The summary said no electrical capacity was recorded while the record showed 720 MW of IT load from the committee report. The summary now matches the figure.
Previously: no electrical capacity figure recorded · Now: 720 MW IT load explained
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — summary
The summary said no capacity was disclosed while the record showed 100 MW of grid-connection capacity. The summary now explains that the figure comes from the operator, not the planning register.
Previously: No capacity figure is disclosed · Now: 100 MW grid-connection capacity explained
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — operator
DC01UK announced the sale of the South Mimms site to Equinix on 30 October 2025, confirmed by BNP Paribas Real Estate. Operator updated; the summary no longer describes the sale as unverified.
Previously: — · Now: Equinix
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — region
Amazon Web Services, Plot 3 Maylands Avenue is in Dacorum, Hertfordshire, which is in the East of England region, not the South East. Region corrected; the project now counts under East of England in the area table and regional hubs.
Previously: South East · Now: East of England
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — region
45 Maylands Avenue, Hemel Hempstead is in Dacorum, Hertfordshire, which is in the East of England region, not the South East. Region corrected; the project now counts under East of England in the area table and regional hubs.
Previously: South East · Now: East of England
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — region
Kao Data Harlow, Plot F is in Harlow, Essex, which is in the East of England region, not the South East. Region corrected; the project now counts under East of England in the area table and regional hubs.
Previously: South East · Now: East of England
27 Sep 2026 · AI Energy Intelligence editorial team
dc_project — region
DC01UK, South Mimms is in Hertsmere, Hertfordshire, which is in the East of England region, not the South East. Region corrected; the project now counts under East of England in the area table and regional hubs.
Previously: South East · Now: East of England
27 Sep 2026 · AI Energy Intelligence editorial team
grid_assessment — Slough and Thames Valley evidence
Regional evidence collection began with Slough and the Thames Valley, using SSEN Distribution's Iver 132kV grid supply point plan. The area covered is wider than Slough and no Slough-only figure is published, so the evidence is recorded at grid-supply-point level and no rating was assigned.
Previously: — · Now: Two evidence records added; rating remains Insufficient evidence
11 Sep 2026 · AI Energy Intelligence editorial team · Methodology v1.0
grid_assessment — London evidence
Regional evidence collection began with London. Substation-level constraint records were added from UK Power Networks' DNOA Outcomes Report. No rating was assigned: the methodology does not yet define the thresholds separating Low, Moderate, High and Severe, and both records come from one publisher.
Previously: — · Now: Two evidence records added; rating remains Insufficient evidence
11 Sep 2026 · AI Energy Intelligence editorial team · Methodology v1.0
datapoint — Reporting period
The 125 GW connection-queue figure was labelled with the publication date of the NESO Grid Code Development Forum slidepack that restated it. Ofgem's consultation document establishes that the figure describes the demand queue as at June 2025. The reading itself is unchanged; only its reporting period, source and supporting notes were corrected.
Previously: As at November 2025 · Now: June 2025
11 Sep 2026 · AI Energy Intelligence editorial team · Methodology v1.0
indicator — Data-centre share of the queue
Ofgem's press release states data centres account for at least 80 GW of the demand queue; Ofgem's consultation document states approximately 73 GW. Neither states the date the subtotal describes. The discrepancy is recorded and the indicator left unavailable rather than one figure being chosen.
Previously: — · Now: Insufficient evidence — sources conflict
11 Sep 2026 · AI Energy Intelligence editorial team · Methodology v1.0
datapoint — New reading
Added the November 2024 observation of the same indicator from Ofgem's consultation document, so the June 2025 figure can be compared against a reading of matching definition and coverage. The change between them is growth in contracted connection offers, not growth in electricity use or in physical grid pressure.
Previously: — · Now: 41 GW, November 2024
11 Sep 2026 · AI Energy Intelligence editorial team · Methodology v1.0
subindex — status_label
DSIT "Estimate of Data Centre Capacity: Great Britain 2024" (published 1 May 2025) re-checked at source on 11 September 2026. GB total 1.6 GW and all eleven regional IT power figures confirmed unchanged; Autumn 2024 reporting period retained. Data Centre Growth Index status moved from "Baseline in development" to "Initial baseline published — coverage expanding".
11 Sep 2026 · AI Energy Intelligence editorial review
indicator — value
The NESO Clean Power 2030 modelling input is no longer presented as the principal baseline. It is retained as historical context with its original classification.
Previously: 5 TWh per year (NESO modelling input) · Now: Superseded by DESNZ 2024 estimate of 4.5 TWh
15 Aug 2026 · AI Energy Intelligence editorial
indicator — value
The official DESNZ share for 2024 replaces an internal calculation whose reporting periods did not match.
Previously: 1.9 per cent (internally calculated) · Now: Superseded by DESNZ 2024 official share of 1.8 per cent
15 Aug 2026 · AI Energy Intelligence editorial
subindex — status_label
Published the first evidence-based baseline for the AI Electricity Demand Index using the DESNZ Energy Trends June 2026 special feature article and its accompanying workbook.
Previously: Baseline in development · Now: 2024 baseline
15 Aug 2026 · AI Energy Intelligence editorial
dc_project — record
New record added following primary-source verification on the London Borough of Hillingdon planning register: hybrid application 78343/APP/2025/719, status Approval, decided 29 October 2025.
Previously: — · Now: published
12 Aug 2026 · Editorial team
dc_project — record
New record added on the basis of Environment Agency permit EPR/TP3530DV and its decision document, issued 27 February 2018. The 214MWth figure is generator thermal input and is excluded from capacity reporting.
Previously: — · Now: published
12 Aug 2026 · Editorial team
dc_project — record
New record added on the basis of Environment Agency permit EPR/PP3225SX, issued 13 September 2023 and recorded as effective on the public register.
Previously: — · Now: published
12 Aug 2026 · Editorial team
dc_project — record
New record added on the basis of Environment Agency permit EPR/QP3533ED and its decision document for Carlton Park Data Centre 1 & 2, operated by Santander UK Plc.
Previously: — · Now: published
12 Aug 2026 · Editorial team
dc_project — record
New record added following primary-source verification on the London Borough of Hillingdon planning register: application 38421/APP/2021/4045, status Approval, decided 26 April 2022.
Previously: — · Now: published
12 Aug 2026 · Editorial team
dc_project — record
New record added following primary-source verification on the Salford City Council planning register: application PA/2024/1810, approved with conditions, decision date 23 July 2025.
Previously: — · Now: published
12 Aug 2026 · Editorial team
dc_project — record
New record added following primary-source verification on the Cardiff Council planning register: application 24/00624/FUL, permission granted, decision issued 15 April 2025.
Previously: — · Now: published
12 Aug 2026 · Editorial team
dc_project — status_publication
Primary-source verification completed on the Northumberland County Council planning register: outline application 24/04112/OUTES permitted, decision issued 8 May 2025, for up to ten data centre buildings totalling 540,000 sqm GIA.
Previously: draft · Now: published
12 Aug 2026 · Editorial team
dc_project — status_publication
Primary-source verification completed on the South Lanarkshire Council planning register. Recorded as proposed: P/25/0490 is an EIA screening opinion (EIA required, issued 25 June 2025), not a planning permission for the campus.
Previously: draft · Now: published
12 Aug 2026 · Editorial team
dc_project — status_publication
Primary-source verification completed on the Northern Ireland Planning Portal: reserved matters application LA11/2023/1729/RM determined and granted on 9 October 2024. Application reference, decision, decision date, applicant and site address corrected against the statutory register.
Previously: draft · Now: published
12 Aug 2026 · Editorial team
dc_project — duplicate_reviewed
Assessed as the same scheme as the Atlantic Hub record at Maydown Road, Derry. No separate planning application exists under the GreenScale name. Held unpublished to prevent double-counting.
Previously: false · Now: true
12 Aug 2026 · Editorial team
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: GreenScale, Foyle Port - proposed (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Haspielaw Farm, Hamilton - proposed (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Next Generation Data Newport campus - operational (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Teledata Wythenshawe - approved (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: AtlasEdge Colombus Way, Salford - approved (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Deep Green Bradford, Listerhills Road - approved (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Skelton Grange, Leeds - proposed (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Cambois data centre campus - proposed (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Cobalt Data Centre Campus (Stellium) - approved (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Kao Data Kenwood Point, Stockport - approved (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Ratcliffe-on-Soar power station site - proposed (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Northtree conversion, Hemel Hempstead - approved (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Amazon Web Services, Plot 3 Maylands Avenue - proposed (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Premier Park data centre, Park Royal - approved (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Kao Data Harlow, Plot F (KLON-07 and KLON-08) - proposed (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Data Centre Campus, Ampthill Road, Bedford - proposed (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Equinix Wexham Road (former AkzoNobel site) - approved (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added and published; primary source from the planning or permitting authority verified.
Previously: — · Now: 1 Redheughs Avenue data centre, South Gyle - refused (published)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added and published; primary source from the planning or permitting authority verified.
Previously: — · Now: Vantage Bridgend campus (former Ford engine plant) - proposed (published)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added and published; primary source from the planning or permitting authority verified.
Previously: — · Now: DC01UK, South Mimms - approved (published)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added and published; primary source from the planning or permitting authority verified.
Previously: — · Now: Manor Farm and land north of Wraysbury Reservoir - approved (published)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added and published; primary source from the planning or permitting authority verified.
Previously: — · Now: VIRTUS Stockley Park campus - operational (published)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added and published; primary source from the planning or permitting authority verified.
Previously: — · Now: Equinix LD8 - operational (published)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added and published; primary source from the planning or permitting authority verified.
Previously: — · Now: Digital Realty Crawley - operational (published)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added and published; primary source from the planning or permitting authority verified.
Previously: — · Now: Global Switch London - operational (published)
12 Aug 2026 · Editorial team · Methodology v1.0
dc_project — record
New project record added as a private draft; evidence insufficient for publication.
Previously: — · Now: Atlantic Hub, Foyle Port - approved (draft)
12 Aug 2026 · Editorial team · Methodology v1.0
datapoint — gb-data-centre-electricity-consumption.limitations
Phase 1 audit: a newer NESO estimate exists. The historical record is retained, not overwritten.
Previously: No limitation recorded · Now: Flagged as superseded by NESO FES 2025 (7.6 TWh); retained as the published November 2024 position.
12 Aug 2026 · AI Energy Intelligence editorial · Methodology 1.0
datapoint — Grid Pressure Index
Phase 4 expansion from the NESO Grid Code Development Forum pack.
Previously: No record · Now: Added total contracted connection demand in the GB queue: 125 GW (November 2025), recorded as an all-technology figure.
12 Aug 2026 · AI Energy Intelligence editorial · Methodology 1.0
datapoint — Data Centre Growth Index
Phase 3 expansion from the DSIT regional capacity table.
Previously: No record · Now: Added colocation data-centre IT capacity for eleven Great Britain regions (autumn 2024), totalling 1.6 GW.
12 Aug 2026 · AI Energy Intelligence editorial · Methodology 1.0
datapoint — Electricity Demand Index
Phase 2 expansion from NESO primary documents opened and read in full.
Previously: No record · Now: Added: GB data-centre demand 7.6 TWh (FES 2025); connected capacity 2.4 GW; GB total demand 263 TWh (2023); GB peak demand 58 GW (2023); GB total demand 287 TWh (2030 forecast); calculated data-centre share 1.9%; 2035 demand 30-41 TWh; 2050 demand 51-71 TWh plus the earlier 62 TWh figure.
12 Aug 2026 · AI Energy Intelligence editorial · Methodology 1.0
indicator — ai-attributable-electricity-demand.caveats
Phase 1 audit: data-gap note required by the methodology.
Previously: No caveat recorded · Now: Recorded why this indicator remains "Insufficient evidence": no reviewed UK source separates AI workloads from wider data-centre consumption.
12 Aug 2026 · AI Energy Intelligence editorial · Methodology 1.0
datapoint — uk-ai-capable-capacity-requirement-2030.value_text
Phase 1 audit: the UK Compute Roadmap says "at least 6GW". The published wording was more precise than the source.
Previously: 6 GW · Now: At least 6 GW
12 Aug 2026 · AI Energy Intelligence editorial · Methodology 1.0
datapoint — gb-data-centre-electricity-consumption-2030.limitations
Phase 1 audit: FES 2025 replaces the Clean Power 2030 demand trajectory. The historical forecast is retained.
Previously: No limitation recorded · Now: Flagged as superseded for forecasting purposes by FES 2025 (30-41 TWh by 2035).
12 Aug 2026 · AI Energy Intelligence editorial · Methodology 1.0
datapoint — gb-colocation-data-centre-capacity.publication_date
Phase 1 audit: the DSIT research and analysis page was published on 1 May 2025; 11 March 2025 is the date the underlying Parliamentary Question answer was first published. Both dates are now recorded.
Previously: 2025-03-11 · Now: 2025-05-01
12 Aug 2026 · AI Energy Intelligence editorial · Methodology 1.0
datapoint — value
First evidence-based baseline entry, verified against the original source document and approved for publication.
Previously: — · Now: 5
11 Aug 2026 · Editorial review
datapoint — value
First evidence-based baseline entry, verified against the original source document and approved for publication.
Previously: — · Now: 6
11 Aug 2026 · Editorial review
datapoint — value
First evidence-based baseline entry, verified against the original source document and approved for publication.
Previously: — · Now: 1.6
11 Aug 2026 · Editorial review
datapoint — value
First evidence-based baseline entry, verified against the original source document and approved for publication.
Previously: — · Now: 22
11 Aug 2026 · Editorial review
Submit a correction
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Source register
| Organisation | Publication or dataset | Published | Indicators supported | Type | Accessed | Notes |
|---|---|---|---|---|---|---|
| Environment Agency | Environmental permit decision document EPR/QP3533ED - Carlton Park Data Centre 1 & 2, Santander UK Plc, Narborough | — | Data Centre Growth Index - project register | official | 12 Aug 2026 | EA decision document: "We have decided to grant the permit for Carlton Park Data Centre 1 & 2 operated by Santander UK Plc." Permit covers standby diesel/DRUPS backup generation only, not IT load. |
| National Energy System Operator (NESO) | Options for optimising GB Data Centres (NIA2_NESO098) | — | Grid pressure — qualitative context only | official | 11 Aug 2026 | Innovation project page. Identifies grid connection availability and power cost among the drivers of data-centre siting and recommends a single consolidated annual view of the GB data-centre estate. Qualitative only: the page publishes no regional constraint figures, so it cannot on its own support a regional grid pressure rating. |
| National Energy System Operator (NESO) | Written evidence to the Environmental Audit Committee (DCU0081) | — | GB data-centre electricity consumption (2030 projection) | operator | 6 Oct 2026 | NESO states that its FES 2025 analysis explored data-centre capacities of 3.7 to 6.3 GW in 2030, with the ten-year forecast at 5.2 GW, giving annual electricity consumption in 2030 of just over 20 TWh. Published by the Committee in 2026; exact publication date not confirmed. NESO adds that its next ten-year forecast (summer 2026) could show higher connected capacity but lower annual demand. |
| Bridgend County Borough Council | Officers' Report, application P/25/247/HYB, former Ford Engine Plant, Bridgend | — | — | official | 12 Aug 2026 | Hybrid application; committee decision not confirmed in the document reviewed. |
| Scottish Government, Planning and Environmental Appeals Division | Case PPA-230-2794, 1 Redheughs Avenue, Edinburgh | — | — | official | 12 Aug 2026 | Appeal following refusal by City of Edinburgh Council. |
| Ofgem | Proposed data centre connection reforms: Curate consultation document | 29 Jul 2026 | Total contracted demand in the GB connection queue; data-centre share of the demand connection queue | regulator | 11 Sep 2026 | Paragraph 2.6 states that between November 2024 and June 2025 total contracted offers in the demand queue rose from 41 GW (17 GW transmission, 24 GW distribution) to 125 GW (97 GW transmission, 29 GW distribution). Paragraph 2.7 states that approximately 73 GW of the total demand queue are data centres, across around 315 projects with contracted capacities from 1 MW to 1,500 MW. Consultation open until 16 September 2026: its reform proposals are proposals, not rules in force. |
| Ofgem | Press release: Ofgem acts to free up grid capacity by tackling speculative data centre projects | 29 Jul 2026 | Data-centre share of the demand connection queue (conflicting figure) | regulator | 11 Sep 2026 | Restates the 41 GW to 125 GW increase between November 2024 and June 2025. Also states data centre projects account for "at least 80GWs" while separately citing "around 73GW referenced in Ofgem's consultation". The two figures are not reconciled in the release, so no data-centre-specific reading is published from it. |
| Department for Energy Security and Net Zero (DESNZ) | Energy Trends, June 2026 - special feature article: Data centre electricity consumption in Great Britain, 2020 to 2024 | 30 Jun 2026 | Great Britain data-centre electricity consumption 2020-2024; data-centre share of grid electricity consumption; regional and local-authority breakdowns | official | 15 Aug 2026 | Accompanying official workbook: Data_centre_electricity_consumption_in_Great_Britain__2020_to_2024.xlsx (https://assets.publishing.service.gov.uk/media/6a3e9f32eaee00074150f678/Data_centre_electricity_consumption_in_Great_Britain__2020_to_2024.xlsx). Worksheets used: Table_1 (consumption, GWh), Table_2 (consumption, TWh, including the percentage change 2020 to 2024), Table_3 (data-centre share of electricity consumed from the grid). The figures are DESNZ statistical estimates of electricity consumed from the public grid by data centres; they are not directly metered totals and are not separated by workload type. |
| Ministry of Housing, Communities and Local Government | Data Centre Campus, Ampthill Road, Bedford in Central Bedfordshire: Section 35 Direction, Planning Act 2008 | 15 Jun 2026 | — | official | 12 Aug 2026 | Direction only; no substantive planning decision. |
| Ministry of Housing, Communities and Local Government | Recovered appeal decision: Manor Farm and land north of Wraysbury Reservoir, Poyle Road, Slough (APP/J0350/W/25/3366043) | 10 Jun 2026 | — | official | 12 Aug 2026 | Secretary of State allowed the appeal subject to conditions. |
| Harworth Group plc | Harworth and Microsoft receive resolution to grant planning consent for hyperscale data centre at Skelton Grange, Leeds | 27 Apr 2026 | — | operator | 12 Aug 2026 | A resolution to grant is not an issued decision notice. |
| Rushcliffe Borough Council | Ratcliffe on Soar Power Station Local Development Order - Proposed Revisions, Cabinet report | 14 Apr 2026 | — | official | 12 Aug 2026 | Order revision only; no specific data-centre scheme, operator or capacity. |
| Old Oak and Park Royal Development Corporation | Planning Committee report, Unit F, 6 Premier Park Road, London NW10 7NZ (25/0196/FUMOPDC) | 26 Feb 2026 | — | official | 12 Aug 2026 | Decision date conflicts with a third-party record; not used for publication pending the decision notice. |
| National Energy System Operator (NESO) | Future Energy Scenarios 2025: Data Workbook (version 6) | 28 Nov 2025 | GB data-centre electricity demand by FES 2025 pathway, 2023 to 2050 | operator | 6 Oct 2026 | Figure F.47 (TWh) and data table ED1 (GWh, "Data Centre Demand", annual, fiscal-year basis). Version 6 uploaded 28 November 2025; first published 14 July 2025. 2050 values: Electric Engagement 70,562 GWh; Holistic Transition 65,317; Hydrogen Evolution 51,242; Falling Behind 30,334. The Ten Year Forecast ends in 2035. |
| National Energy System Operator (NESO) | Grid Code Development Forum, 5 November 2025 - Large Demand Technical Requirements | 5 Nov 2025 | GB data-centre demand and connected capacity; FES 2025 pathway demand for 2035 and 2050; contracted connection demand in the queue | operator | 12 Aug 2026 | NESO industry forum pack. Slide 10 states current GB data-centre demand, connected capacity and pathway figures, citing FES 2025 and Energy Networks Association connections data. |
| National Energy System Operator (NESO) | Grid Code Development Forum slidepack, 5 November 2025 — Large Demand Technical Requirements | 5 Nov 2025 | Total contracted demand in the GB connection queue (restatement) | operator | 11 Sep 2026 | Slide 10 states "Total Contracted Connection Demand in the queue: 125 GW", footnoted to Energy Networks Association connections data. The slidepack does not state the date the 125 GW figure describes. Retained as supporting evidence only; the reporting date is taken from the Ofgem consultation, which states the figure is as at June 2025. |
| London Borough of Hillingdon | Planning application 78343/APP/2025/719 - Hybrid four-phase data centre campus, Hayes Bridge Retail Park and Heathrow Interchange, Uxbridge Road, Hayes | 29 Oct 2025 | Data Centre Growth Index - project register | official | 12 Aug 2026 | Statutory register: Status "Approval", Decided 29-10-25. Hybrid application: Phase 1 full, Phases 2-4 outline. No capacity stated. |
| Department for Energy Security and Net Zero (DESNZ) / Europe Economics | Impact of growth of data centres on energy consumption | 14 Aug 2025 | Context and methodology only — supports no national total | official | 11 Aug 2026 | Reviewed and found to contain no UK data-centre electricity consumption or capacity total. The study compares digital service delivery with physical alternatives across individual use cases (video streaming, eBooks, AI translation, and ten further cases in the follow-up study). Registered for methodological context only; no index value is derived from it. |
| Salford City Council | Planning application PA/2024/1810 - Data centre and ancillary office, former White's Reclamation Site, Liverpool Road, Eccles | 23 Jul 2025 | Data Centre Growth Index - project register | official | 12 Aug 2026 | Statutory register: Status "Decision Made", Decision "Approve with Conditions", Decision date 23/07/2025. Planning Panel, committee 06/02/2025. Applicant listed as "c/o agent". |
| Department for Science, Innovation and Technology (DSIT) and UK Research and Innovation (UKRI) | UK Compute Roadmap | 17 Jul 2025 | UK AI-capable data-centre capacity requirement (2030 forecast) | official | 8 Oct 2026 | First published 17 July 2025, as confirmed by the GOV.UK publication landing page; that page was last updated 23 April 2026 following changes to the Compute Evidence Annex. The roadmap forecasts a need for at least 6 GW of AI-capable data-centre capacity by 2030 and states that demand could exceed this baseline. This is a forecast requirement, not installed capacity. The document does not define whether AI-capable capacity refers to IT load, facility load or grid-connection capacity. |
| National Energy System Operator (NESO) | Future Energy Scenarios 2025: Pathways to Net Zero | 1 Jul 2025 | GB data-centre electricity demand; 2035 and 2050 pathway demand | official | 12 Aug 2026 | FES 2025 rebuilt the data-centre demand model using DNO and TO connection information. Pathway figures are scenarios, not predictions. |
| South Lanarkshire Council | Planning application P/25/0490 - EIA screening opinion request, proposed data centre campus, Haspielaw Farm, Hamilton | 25 Jun 2025 | Data Centre Growth Index - project register | official | 12 Aug 2026 | Statutory register: Screening Opinion request. Status Decided. Decision "Screening opinion - EIA required", issued 25 Jun 2025. Not a planning permission. |
| Environment Agency | RH10 9BD, Digital Realty (UK) Limited: environmental permit issued | 9 Jun 2025 | — | regulator | 12 Aug 2026 | Standby generation permit for the Crawley campus. |
| Northumberland County Council | Planning application 24/04112/OUTES - Outline application for up to ten data centre buildings, former power station site, Cambois | 8 May 2025 | Data Centre Growth Index - project register | official | 12 Aug 2026 | Statutory register: Status Permitted, Decision "Application Permitted", Decision Issued 08 May 2025, committee decision 04 Mar 2025. Applicant Renaissance Land Limited. |
| Department for Science, Innovation and Technology (DSIT) | Estimate of Data Centre Capacity: Great Britain 2024 | 1 May 2025 | GB colocation data-centre capacity (maximum rated IT load) | official | 8 Oct 2026 | Restates the answer to Parliamentary Question HL5239, answered 11 March 2025. Evidence located in the body table "IT power (MW)" by ITL1 region, with a stated total of 1.6 gigawatts. Capacity is defined as the maximum rated IT load of colocation data centres and excludes enterprise data centres. Figures are modelled estimates informed by industry engagement and are rounded. |
| Scottish and Southern Electricity Networks (SSEN) Distribution | Iver 132kV Grid Supply Point Strategic Development Plan (draft for consultation), May 2025 | 1 May 2025 | Regional grid evidence: Slough and the Thames Valley | operator | 11 Sep 2026 | Covers the Iver 132kV Grid Supply Point area, which SSEN describes as serving communities across Windsor and Slough, with sections addressing Slough, Windsor and Maidenhead, Buckinghamshire, Spelthorne, Hillingdon and Surrey councils. Draft published for consultation. Future network needs are modelled from DFES 2023 scenarios. |
| Cardiff Council | Planning application 24/00624/FUL - Energy park and data centre, Land at Rover Way, Splott, Cardiff | 15 Apr 2025 | Data Centre Growth Index - project register | official | 12 Aug 2026 | Statutory register: Status Decided, Decision "Permission Granted", Decision Issued Date 15 Apr 2025. Committee resolution 17 Oct 2024 subject to S106; permission subsequently issued. |
| UK Power Networks | Distribution Network Options Assessment (DNOA) Outcomes Report, March 2025, third edition | 1 Mar 2025 | Regional grid evidence: London Power Networks substation constraints | operator | 11 Sep 2026 | Substation-level constraint assessments for UK Power Networks' three licence areas. London entries used here are in the London Power Networks (LPN) results section, page 49. Flexibility requirements are stated per DFES 2024 scenario and are therefore scenario forecasts, not measured shortfalls. |
| Hertsmere Borough Council | Data centre in Hertsmere given outline permission by planning committee | 23 Jan 2025 | — | official | 12 Aug 2026 | Planning authority's own record of the committee decision. |
| National Energy System Operator (NESO) | Clean Power 2030 — Annex 1: Electricity demand and supply analysis | 5 Nov 2024 | GB data-centre electricity consumption (baseline and 2030 projection) | official | 11 Aug 2026 | Evidence located on page 4, section 2.1.3 "Basis for our analysis": "Growth in data centres (from 5 TWh today) is based on registers of planning and grid connection applications to 22 TWh in 2030." Figures are modelling inputs to the Clean Power 2030 pathway, not measured statistics, and cover all data centres rather than AI workloads specifically. |
| Derry City and Strabane District Council (Northern Ireland Planning Portal) | Planning application LA11/2023/1729/RM - Erection of one IT service and data centre buildings, Maydown Road, Derry | 9 Oct 2024 | Data Centre Growth Index - project register | official | 12 Aug 2026 | Statutory planning register entry. Status: Determined. Decision: Granted. Applicant: Atlantic Hub Property Limted (as spelled on the register). |
| Environment Agency | Decision document EPR/DP3906BE/A001 (Equinix LD8, Slough) | 16 Oct 2023 | — | regulator | 12 Aug 2026 | Permit covers 64 MWth generator thermal input, not IT load. |
| Environment Agency | Public register entry EPR/PP3225SX - Enfield DC Service Company Limited, VIRTUS LONDON1 data centre, Crown Road, Enfield | 13 Sep 2023 | Data Centre Growth Index - project register | official | 12 Aug 2026 | EA public register: permit EPR/PP3225SX, holder Enfield DC Service Company Limited, issued 13/09/2023, status Effective. No capacity value on the register entry. |
| London Borough of Hillingdon | Planning application 38421/APP/2021/4045 - Data centre campus, Land at Tudor Works, Beaconsfield Road, Hayes | 26 Apr 2022 | Data Centre Growth Index - project register | official | 12 Aug 2026 | Statutory register: Status "Approval", Decided 26-04-22. Agent Savills. No capacity or floorspace stated on the register entry. |
| Environment Agency | Decision document EPR/AP3903PD/A001 (VIRTUS Stockley Park) | 16 Nov 2021 | — | regulator | 12 Aug 2026 | Permit granted for London 5 and 6; refused in part for London 7 and 8. |
| Environment Agency | E14 9YY, Global Switch Limited: environmental permit issued | 28 Jun 2019 | — | regulator | 12 Aug 2026 | Permit covering the East India Dock Road site. |
| Environment Agency | Environmental permit decision document EPR/TP3530DV - Digital Realty (UK) Limited, Kestrel Way, Woking | 27 Feb 2018 | Data Centre Growth Index - project register | official | 12 Aug 2026 | EA decision document: 65 diesel standby generators, "aggregated total combustion capacity on site is 214MWth". This is generator thermal input, NOT IT load, facility load or grid connection capacity. |