Grid Code

The Grid Code covers all material technical aspects relating to connections to, and the operation and use of, the national electricity transmission system.

The Grid Code is available to view on the National Grid Electricity Transmission website.

Grid Code Modifications

Our decisions on proposed changes to this code are included below.

Publications and updates

  • Published: 20th Dec 2010
  • Other
  • 1 Associated documents
This change to the Grid Code proposes housekeeping amendments that impove the clarity and robustness of the Grid Code legal text.

  • Published: 17th Dec 2010
  • Other
  • 1 Associated documents
See the Grid Code F/10: Code Governance Review - Environmental Assessment.

  • Published: 5th Nov 2010
  • Other
  • 1 Associated documents
This letter sets out our decision to reject B/09.

  • Published: 4th Oct 2010
  • Other
  • 1 Associated documents
This change seeks to improve flexibility and timely provision of Detailed Planning Data by Users after National Grid makes a transmission connection offer.

  • Published: 23rd Aug 2010
  • Other
  • 1 Associated documents
This change seeks to allow a lower Short Circuit Ratio (SCR) value (0.4 instead of 0.5) to apply to single generating units with a rated output of 1600MVA or above.

  • Published: 27th Jan 2010
  • Other
  • 1 Associated documents
This proposal adds clarity and consistency to the requirements of operating the Low Frequency Demand Disconnection (LFDD) scheme for both users and National Grid.

  • Published: 20th Jan 2010
  • Other
  • 1 Associated documents
Change obliges interconnector owners to provide National Grid with data of their forecast availability to improve system planning.

  • Published: 30th Apr 2009
  • Other
  • 1 Associated documents
See the Grid Code change reviewing the Reactive Power requirements for Synchronous Generating Units exceeding rated MW.

  • Published: 19th Mar 2009
  • Other
  • 1 Associated documents
Reviewing the requirements to provide forecast generation output for Embedded Exemptible Large Power Stations (EELPS).

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