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gb_enwl_heatmaps

ENWL capacity heatmaps

Published by SP Electricity North West · GB · Monthly

Archived, pending reviewpending_reviewDisabled

Firm and N-0 demand headroom, N-0 generation headroom by generator type and battery headroom (MW) at every ENWL primary and BSP, and the Appendix G transmission position of every GSP, as ENWL's portal datasets.

What is withheld, and why

Every value from this source is withheld. The operator’s terms do not clearly allow us to redistribute its figures, and when signals conflict the more restrictive reading wins until the operator confirms otherwise in writing. Records are still listed — with capacity.value null, access.status "withheld" and a link to the publication — so you know the operator publishes something there.

The publication is still read and kept, because operators overwrite their files and a history not recorded when it happened can never be recovered. If reuse is cleared, customers get the history as well as the present.

The signals conflict. Each dataset's licence field says CC BY 4.0 and its description "Dataset Classification - Open"; the portal's terms-and-conditions link redirects to the enwl.co.uk website terms, which forbid commercial use without a licence, and ENWL also publishes a Shared Data Licence without saying which datasets it covers. Per source-governance §4 the more restrictive reading wins until ENWL confirms otherwise in writing (dataportal@enwl.co.uk), so values are fetched and kept but not served.

Licence and rights evidence

Licence
CC BY 4.0 (dataset field), under enwl.co.uk terms (portal) (opens the operator’s site)
Attribution
SP Electricity North West, SP ENW - Capacity - PRY / BSP / GSP Heatmap, https://electricitynorthwest.opendatasoft.com/required
Technical access
Not established
Commercial use
Not established
May be cached
Not established
May be redistributed
Not established
Derived data allowed
Not established

Evidence

Methodology

2 version(s)

ENWL capacity heatmaps — primary and BSP headroom

gb_enwl_heatmaps_2026 · v2026-09

Spare capacity estimated by a high-level assessment of thermal loading of circuits and transformers, fault level and voltage step change, per connection type; primary figures take account of constraints at the associated BSP.

Capacity basis
operator calculated
Network state
unknown
Binding
No
Additive across assets
No — do not sum these figures
The method accounts for
reserved: not stated · allocated: not stated · pre-reserved: not stated · pending requests: not stated
Comparability class
gb_enwl_heatmap
Documentation
Operator’s method (opens the operator’s site)

The operator’s own caveats

  • Please note that the data presented in this tool is based on high level analysis and as such may differ from the results of a formal connection application.

ENWL capacity heatmaps — GSP Appendix G summary

gb_enwl_heatmaps_appendix_g_2026 · v2026-09

The Appendix G return per converted GSP: connected and contracted power stations in Parts 1–4, the materiality headroom NESO determines at the transmission interface (Part 5), capacity in project progression, and the aggregated developer capacity limit.

Capacity basis
operator published
Network state
unknown
Binding
No
Additive across assets
No — do not sum these figures
The method accounts for
reserved: not stated · allocated: not stated · pre-reserved: not stated · pending requests: not stated
Comparability class
gb_enwl_appendix_g
Documentation
Operator’s method (opens the operator’s site)

The operator’s own caveats

  • Note that the capacities reported in the table above were true prior to the ongoing Connections Reform, hence only indicative.

How the publication maps to the model

availability types
["available","connected","contracted","requested","total","unknown"]
binding
false
directions
["offtake","injection","bidirectional"]
firmness
["firm","conditional","unknown"]
geometry precision
approximate
includes reserved projects
null
non additive
true
notes
["The column meanings are those of the Heatmap Tool's user guide: dem_hr_firm_mw is firm (\"secure for the loss of a single circuit\"); dem_hr_non_firm_mw, the generation and the battery columns are N-0 (\"constrained off for the loss of the first circuit\") and conditional.","Inverter-based and LV / HV synchronous generation are generic_generation with the operator's split as the variant; battery storage (MIC equal to MEC) is one bidirectional value.","The GSP dataset is Appendix G, a separate methodology: Part 1 connected, Parts 2 and 3 (\"connected or contracted to connect\") unknown, Part 4 contracted, Part 5 materiality headroom available, capacity in project progression requested, total aggregated developer capacity limit total. Transmission fault-level headroom (kA) is an attribute.","Assets are keyed by ENWL's own PRY_NUMBER / BSP_NUMBER / GSP_NUMBER, which the schema publishes and the workbook does not; the schema has no name field, so the number is also the name.","The polygons are \"interlocking Voronoi polygons\", schematic rather than supply areas, and are not fetched; geo_point_2d beside them is kept as an approximate location.","The primary dataset's voltage column is labelled VOLTAGE__MW_; it is kept as an attribute and not read as kV."]
spatial scope
substation
technologies
["generic_load","generic_generation","battery"]
units
["MW"]

Query this source

curl "https://api.gridcapacityapi.com/v1/capacity/search?source=gb_enwl_heatmaps&limit=20" \  -H "Authorization: Bearer gc_live_..."