The National Energy System Operator (NESO) is Great Britain's publicly owned, operationally independent electricity system operator and whole-energy system planner, created on 1 October 2024 when the UK government purchased National Grid Electricity System Operator Limited and folded in gas system planning from National Gas Transmission. NESO balances the GB electricity system in real time, runs the connections queue, publishes Future Energy Scenarios, and sits at the centre of the value chain between generators, interconnectors, transmission and distribution networks, and suppliers. Its API posture is the sector's classic split, and NESO lands firmly on the open side of that split. Market and system data is genuinely open and anonymous - the NESO Data Portal exposes 128 datasets over a public CKAN API at api.neso.energy with no key, no account and no application, all under the permissive NESO Open Data Licence, and the Carbon Intensity API for Great Britain that NESO develops is one of the most openly consumed public energy APIs in the world. There is no consumer data surface at all, and none is expected, because NESO holds no retail customer relationships, Britain has no consumer energy data-portability mandate comparable to the Australian Consumer Data Right, and smart-meter consumption data travels through the licensed Smart DCC monopoly rather than through the system operator. NESO's open-data obligation comes from Ofgem's Data Best Practice Guidance embedded in its RIIO-2 licence, and unlike most of the sector that obligation is visibly implemented rather than merely claimed.
National Energy System Operator (NESO) publishes 2 APIs on the APIs.io network. Tagged areas include Energy, United Kingdom, Electricity, Energy Markets, and Grid.
National Energy System Operator (NESO)’s developer surface includes authentication, documentation, developer portal, API reference, support, product news, and 23 more developer resources.
Regulatory Posture applies to this provider. Its tags matched the
Energy & Utilities regime, so
Regulatory Posture carries 15 points of the composite.
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Create-or-Update Ergonomics could not be measured. We hold no machine-readable contract for
this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero:
never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and
several others — scorable at all.
The six quality facets above are damped to 85 points between them,
because the conditional facet above carries the other
15. That is why each facet's contribution is shown against a damped
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The public CKAN 2.8.7 API behind the NESO Data Portal, serving 128 open datasets covering GB electricity demand, generation, balancing, ancillary services, constraints, intercon...
The official Carbon Intensity API for Great Britain, developed by NESO, giving national and regional carbon intensity of GB electricity - actual, forecast up to 96+ hours ahead,...
aid: neso
url: https://raw.githubusercontent.com/api-evangelist/neso/refs/heads/main/apis.yml
name: National Energy System Operator (NESO)
kind: company
description: The National Energy System Operator (NESO) is Great Britain's publicly owned, operationally independent electricity
system operator and whole-energy system planner, created on 1 October 2024 when the UK government purchased National Grid
Electricity System Operator Limited and folded in gas system planning from National Gas Transmission. NESO balances the
GB electricity system in real time, runs the connections queue, publishes Future Energy Scenarios, and sits at the centre
of the value chain between generators, interconnectors, transmission and distribution networks, and suppliers. Its API posture
is the sector's classic split, and NESO lands firmly on the open side of that split. Market and system data is genuinely
open and anonymous - the NESO Data Portal exposes 128 datasets over a public CKAN API at api.neso.energy with no key, no
account and no application, all under the permissive NESO Open Data Licence, and the Carbon Intensity API for Great Britain
that NESO develops is one of the most openly consumed public energy APIs in the world. There is no consumer data surface
at all, and none is expected, because NESO holds no retail customer relationships, Britain has no consumer energy data-portability
mandate comparable to the Australian Consumer Data Right, and smart-meter consumption data travels through the licensed
Smart DCC monopoly rather than through the system operator. NESO's open-data obligation comes from Ofgem's Data Best Practice
Guidance embedded in its RIIO-2 licence, and unlike most of the sector that obligation is visibly implemented rather than
merely claimed.
deliveryModel:
model: unknown
open_source: unknown
commercial: true
callable_host: false
label: Delivery model not determined — needs a product licence on record
confidence: low
source:
- pricing
- repository-unlicensed
generated: '2026-08-28'
method: derived
accessModel:
pricing: free
onboarding: open
trial: false
try_now: true
public: true
label: Free - Open, no registration
confidence: high
source:
- probe
generated: '2026-07-27'
method: observed
image: https://www.neso.energy/themes/custom/neso_theme/logo.svg
tags:
- Energy
- United Kingdom
- Electricity
- Energy Markets
- Grid
- Open Data
- Carbon
- Renewables
- Gas
- Demand Response
created: '2026-07-27'
modified: '2026-07-27'
specificationVersion: '0.23'
apis:
- aid: neso:neso-data-portal-api
name: NESO Data Portal API
description: The public CKAN 2.8.7 API behind the NESO Data Portal, serving 128 open datasets covering GB electricity demand,
generation, balancing, ancillary services, constraints, interconnectors, connection registers, network charges, the Demand
Flexibility Service, and Future Energy Scenarios. Anonymous and unauthenticated - package_list, package_search, package_show,
resource_search, resource_show, datastore_search and datastore_search_sql (PostgreSQL) all answer 200 with no key. All
128 datasets carry the NESO Open Data Licence. NESO asks for a maximum of one request per second against the CKAN API
and two requests per minute against the datastore.
humanURL: https://www.neso.energy/data-portal/api-guidance
baseURL: https://api.neso.energy/api/3/action
tags:
- Open Data
- Energy Markets
- Electricity
- Demand
- CKAN
properties:
- type: Documentation
url: https://www.neso.energy/data-portal
- type: APIReference
url: https://www.neso.energy/data-portal/api-guidance
- type: Licensing
url: https://www.neso.energy/data-portal/neso-open-licence
- type: RateLimits
url: rate-limits/neso-rate-limits.yml
- type: Authentication
url: authentication/neso-authentication.yml
- type: Conventions
url: conventions/neso-conventions.yml
- type: ErrorCatalog
url: errors/neso-error-codes.yml
- type: DataModel
url: data-model/neso-data-model.yml
- aid: neso:neso-carbon-intensity-api
name: Carbon Intensity API
description: The official Carbon Intensity API for Great Britain, developed by NESO, giving national and regional carbon
intensity of GB electricity - actual, forecast up to 96+ hours ahead, half-hourly generation mix, per-fuel emission factors,
and regional breakdowns by DNO region, region id, or postcode. Fully anonymous REST/JSON over HTTPS with no API key and
no registration; documented as a Slate reference site rather than as a downloadable OpenAPI contract.
humanURL: https://carbon-intensity.github.io/api-definitions/
baseURL: https://api.carbonintensity.org.uk
tags:
- Carbon
- Electricity
- Renewables
- Grid
- Open Data
properties:
- type: APIReference
url: https://carbon-intensity.github.io/api-definitions/
- type: Documentation
url: https://carbonintensity.org.uk/
- type: GitHubOrganization
url: https://github.com/carbon-intensity
- type: SourceCode
url: https://github.com/carbon-intensity/api-definitions
- type: TermsOfService
url: https://github.com/carbon-intensity/terms
- type: Authentication
url: authentication/neso-authentication.yml
- type: Conventions
url: conventions/neso-conventions.yml
- type: ErrorCatalog
url: errors/neso-error-codes.yml
- type: DataModel
url: data-model/neso-data-model.yml
common:
- type: IssueTracker
url: https://github.com/carbon-intensity/api-definitions/issues
- type: VulnerabilityDisclosure
url: security/neso-vulnerability-disclosure.yml
- type: Security
url: https://www.neso.energy/responsible-disclosure
- type: SecurityTxt
url: well-known/neso-security.txt
- type: DomainSecurity
url: security/neso-domain-security.yml
- type: WellKnown
url: well-known/neso-well-known.yml
- type: Authentication
url: authentication/neso-authentication.yml
- type: Conventions
url: conventions/neso-conventions.yml
- type: RateLimits
url: rate-limits/neso-rate-limits.yml
- type: ErrorCatalog
url: errors/neso-error-codes.yml
- type: Lifecycle
url: lifecycle/neso-lifecycle.yml
- type: Conformance
url: conformance/neso-conformance.yml
- type: DataModel
url: data-model/neso-data-model.yml
- type: Packages
url: packages/neso-packages.yml
- type: X-MCPServerCandidate
url: mcp/neso-mcp.yml
note: 'Renamed from MCPServer 2026-09-03 (roadmap#247): the manifest self-describes as status: candidate — a tool list derived
from the published API contracts, not an existing server. The scorer already read the manifest and reported mcp_server
correctly; the MCPServer type was crediting the artifact-type surfaces with a server that does not exist.'
- type: AgentSkill
url: skills/_index.yml
- type: LLMsTxt
url: llms/neso-llms.txt
- type: Website
url: https://www.neso.energy/
- type: Documentation
url: https://www.neso.energy/data-portal/api-guidance
- type: Portal
url: https://www.neso.energy/data-portal
- type: APIReference
url: https://carbon-intensity.github.io/api-definitions/
- type: Licensing
url: https://www.neso.energy/data-portal/neso-open-licence
- type: TermsOfService
url: https://www.neso.energy/terms-and-conditions
- type: PrivacyPolicy
url: https://www.neso.energy/privacy-policy
- type: Support
url: https://www.neso.energy/contact-us
- type: GitHubOrganization
url: https://github.com/carbon-intensity
- type: LinkedIn
url: https://www.linkedin.com/company/neso-energy
- type: BlogRSS
url: https://www.neso.energy/rss.xml
- type: News
url: https://www.neso.energy/news
maintainers:
- FN: Kin Lane
email: kin@apievangelist.com
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