GB Capacity Market Register Scraper – NESO CMU, Agreements & Components

Get every Capacity Market Unit (CMU) in Great Britain's official Capacity Market Register as clean JSON, CSV or Excel, straight from NESO's (National Energy System Operator, formerly National Grid ESO) open-data API. That covers T-4, T-3, T-1 and transitional auctions, delivery years, applicant and parent company, technology (batteries/BESS, CCGT, DSR, interconnectors, solar, wind…), connection and de-rated capacity, capacity agreements and obligations, plus each CMU's component sites (location, postcode district, OS grid reference). There's one record per CMU, so you no longer have to download and join two 30,000-row CSVs.

What data does it return?

• Auction: delivery year, auction type and name, application ID, prequalification decision, opt-in/out status
• Who: CMU ID and name, applicant, parent company, registered holder, agent
• What: CMU type and category (new build, refurbishing, existing, DSR…), technology, primary fuel, storage flag
• How much: connection capacity MW, de-rated capacity MW, capacity obligation MW, credit cover
• Agreement: awarded or not, agreement ID, duration (years), delivery years, issue date, FCM and long-stop dates, termination and suspension
• Components: component ID, description, technology class, MW, location, postcode district, OS grid reference

Who is it for?

• BESS and flexibility developers: see who won T-4/T-1 agreements, at what size and where
• Traders, aggregators and VPPs: track competitors' capacity portfolios and obligations
• Investors, lenders and consultants: due diligence on projects, parents and agreement terms
• Analysts and journalists: technology mix and new-build pipeline by delivery year

How to use it

1. Click Try for free / Start.
2. Choose delivery years and auction types, and optionally technology keywords (e.g. Storage, DSR) or company keywords (e.g. a parent company name).
3. Set Max results to cap the run and your cost.
4. Run it, then export as JSON, CSV or Excel, or read the results through the Apify API.

Input example

{"deliveryYears": [2029], "auctionTypes": ["T-4"], "technologyKeywords": ["Storage"], "agreementAwardedOnly": true, "maxItems": 100}

Input reference

Field	Description
deliveryYears	e.g. [2028, 2029] (2029 = Oct 2029–Sep 2030). Empty = all.
auctionTypes	T-4, T-3, T-1, TR, ST. Empty = all.
technologyKeywords	e.g. "Storage", "DSR", "CCGT", "Solar".
companyKeywords	Applicant / parent / holder / agent / CMU name, e.g. "Statkraft".
cmuIds	Exact CMU IDs.
agreementAwardedOnly / prequalifiedOnly / excludeTerminated	Status filters.
minDeRatedCapacityMw	Minimum de-rated MW.
includeComponents	Attach component sites (default on, no extra charge).
maxItems	Stop after N CMUs (default 500).

Output example

One dataset item per CMU. This record is from a real test run (first component shown):

{
  "applicationId": "A-T-4-2029-10TEAL-00001",
  "cmuId": "10TEAL",
  "cmuName": "Tealing",
  "auctionName": "2029-30 (T-4) Four Year Ahead Capacity Auction",
  "auctionType": "T-4",
  "deliveryYear": 2029,
  "applicant": "GPC 1039 LTD",
  "parentCompany": "Apatura Battery Ltd",
  "agent": null,
  "registeredHolder": "GPC 1039 LTD",
  "transmissionOrDistribution": "Transmission",
  "cmuType": "CMRS",
  "cmuCategory": "New Build Generating CMU",
  "technology": "Storage (Duration 2h)",
  "primaryFuel": "Storage - Battery",
  "storage": true,
  "prequalificationDecision": "Prequalified",
  "optOutStatus": "Opt-In",
  "connectionCapacityMw": 67,
  "deRatedCapacityMw": 14.727,
  "capacityAgreementAwarded": true,
  "agreementId": "CAN-2029-10TEAL-001",
  "agreementDurationYears": 15,
  "agreementIssueDate": "07/04/2026",
  "agreementTerm": "15",
  "agreementDeliveryYears": "2029/2030, 2030/2031, 2031/2032, 2032/2033, 2033/2034, 2034/2035, 2035/2036, 2036/2037, 2037/2038, 2038/2039, 2039/2040, 2040/2041, 2041/2042, 2042/2043, 2043/2…",
  "capacityObligationMw": 14.727,
  "fcmRequired": true,
  "fcmDate": "20/07/2027",
  "minimumCompletionLongStopDate": "01/10/2030",
  "creditCoverGbp": 147270,
  "terminated": null,
  "terminationDate": null,
  "suspended": null,
  "components": [
    {
      "componentId": "TEAL10",
      "description": "Front of meter BESS plant. The Connection Capacity stated is lower than the BESS capacity and the connection agreement - this is to allow for degradation of the battery over 15 years in order to pass the Extended Performance Test.",
      "technologyClass": "Storage (Duration 2h)",
      "primaryFuel": "Storage - Battery",
      "connectionCapacityMw": 67,
      "deRatedCapacityMw": 14.727,
      "location": "Myreton BESS, Land at Balnuith, Myreton of Claverhouse, Tealing, DD3",
      "postcodeDistrict": "DD3",
      "osGridReference": "NO 396 371"
    }
  ],
  "componentCount": 1,
  "sourceUrl": "https://www.neso.energy/data-portal/capacity-market-register",
  "attribution": "Supported by National Energy SO Open Data",
  "license": "National Energy SO Open Data Licence v1.0 (https://www.neso.energy/data-portal/neso-open-licence)",
  "sourceUpdatedAt": "2026-10-28T08:47:58.881976",
  "scrapedAt": "2026-10-29T12:05:40.032Z"
}

Newest delivery year first.

How much does it cost?

Pay per result: $0.005 per CMU record ($5 per 1,000). Components are included free. Filtering happens server-side, so you only pay for matching CMUs. Set a max charge per run and the Actor stops cleanly when it is reached.

CMU records	Cost
100	$0.50
1,000	$5.00
10,000	$50.00

Coverage

All CMUs in the NESO Capacity Market Register (CMU + Component resources), all auctions and delivery years published by NESO. Refreshed by NESO as auctions and agreement changes are processed; each record carries sourceUpdatedAt.

Legal and data protection

Source: the NESO Data Portal (National Energy System Operator), published under the NESO Open Data Licence v1.0 (based on the Open Government Licence v3.0): "You are free to: copy, publish, distribute and transmit the Information; adapt the Information; exploit the Information commercially and non-commercially for example, by combining it with other Information, or by including it in your own product or application." Every record carries the required attribution "Supported by National Energy SO Open Data" and a link to the source dataset. This Actor is not affiliated with or endorsed by NESO.

The Actor uses NESO's official CKAN API only (no scraping, no login) and follows NESO's rate guidance (at most two datastore requests per minute), so multi-source runs take ~30 s per extra query.

Organisation data only: the register's "secondary trading contact" telephone/email columns and security-interest fields are never requested or output (some contain personal emails). Full postcodes in component locations are cut to the postcode district (outward code). You are responsible for your own UK GDPR compliance.

FAQ

• Why a CMU per record rather than per component? That's how agreements are awarded. Components are nested, so a 300-component DSR CMU is still one result.
• Is this the official data? Yes. It reads NESO's own datastore, the same data behind the Capacity Market Register CSV.
• Is NESO the same as National Grid ESO? Yes. The Electricity System Operator became the National Energy System Operator (NESO) in October 2024.
• Can I schedule it? Yes. Use Apify Schedules (e.g. weekly) and integrations (webhooks, Make, Zapier, Google Sheets) to push updates where you need them.
• Need another field or dataset? Open an issue on the Actor page.