Day Ahead Constraint Flows and Limits

The data below is a snapshot of the limits and flows at relevant boundaries at day ahead stage. These flow values are calculated at Day Ahead and will not reflect any changes in the flows following the publication of this data. The boundary flows are the forecast position after Day Ahead energy scheduling has been run.

Please note that from the 22nd April 2024 the flows no longer consider expected constraint mitigation or optimisation actions. Before this date the data did consider constraint mitigation actions. This change has happened as the software used to collate this information has been updated. N.B. The data for NKILGRMO is not currently available.

The network diagrams show the constraint boundaries and arrows indicating the positive direction of power flow across each boundary.

CKAN Data API

Access resource data via a web API with powerful query support.
Further information in the main CKAN Data API and DataStore documentation.

The Data API can be accessed via the following actions of the CKAN action API.

Query
`https://api.nationalgrideso.com/api/3/action/datastore_search`
Query (via SQL)
`https://api.nationalgrideso.com/api/3/action/datastore_search_sql`

Query example (first 5 results)
`https://api.nationalgrideso.com/api/3/action/datastore_search?resource_id=38a18ec1-9e40-465d-93fb-301e80fd1352&limit=5`
Query example (via SQL statement)
`https://api.nationalgrideso.com/api/3/action/datastore_search_sql?sql=SELECT * from "38a18ec1-9e40-465d-93fb-301e80fd1352" LIMIT 5`

A simple ajax (JSONP) request to the data API using jQuery.

var data = {
  resource_id: '38a18ec1-9e40-465d-93fb-301e80fd1352', // the resource id
  limit: 5 // get 5 results
};
$.ajax({
  url: 'https://api.nationalgrideso.com/api/3/action/datastore_search',
  data: data,
  dataType: 'jsonp',
  success: function(data) {
    alert('Total results found: ' + data.result.total)
  }
});

A simple ajax (JSONP) request to the data API using jQuery.

import urllib2
  url = 'https://api.nationalgrideso.com/api/3/action/datastore_search?resource_id=38a18ec1-9e40-465d-93fb-301e80fd1352&limit=5'
  fileobj = urllib2.urlopen(url)
  print fileobj.read()

Download (CSV)

Data Explorer

Table Information

Constraint Group

Title	Constraint Group
Type	string
Description	The geographical area in which the constraint occurred. Each group has its own unique code, which relates to the network diagram linked above. The ten most important boundaries are included in this data file.
Comment
Example	ESTEX
Unit

Date (GMT/BST)

Title	Date (GMT/BST)
Type	datetime
Description	The date and time for the given limit and flow through the constraint boundary. This is given in a MM/DD/YYYY HH:MM format. The flow and limit for each constraint group is given for a day, before moving onto the next day. Data is given on a settlement period (half hourly) basis.
Comment
Example	2019-01-10T03:30:00
Unit

Limit (MW)

Title	Limit (MW)
Type	integer
Description	The maximum amount of power that can flow through a constraint boundary.
Comment
Example	5450
Unit	MW

Flow (MW)

Title	Flow
Type	number
Description	A snapshot of the power flows across a number of important constraint boundaries at day ahead. This power flow forecast is created based on the next day’s wind forecast, generation dispatch and demand forecast and is modelled using power system software.
Comment
Example
Unit

For any queries or feedback please contact [email protected]

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Day Ahead Constraint Flows and Limits

CKAN Data API

Data Explorer

Data Explorer

Table Information

Constraint Group

Date (GMT/BST)

Limit (MW)

Flow (MW)