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  • Industry information
  • Codes Homepage

System Operator Transmission Owner Code (STC)

The System Operator Transmission Owner Code defines the relationship between the transmission system owners and the system operator.

As the code administrator for the STC, we maintain the code and oversee any proposed changes to it. All changes have to be reviewed by the STC modification Panel and approved by the Panel, or by Ofgem.

You can find out more about the roles and responsibilities of everyone involved in the STC procedures document, on the Code documents page.

For more information about the code, please contact stcteam@nationalgrideso.com.

You can subscribe to the STC mailing list here.

STC Menu

OverviewModificationsCalendarPanel and Meeting DocumentsCode DocumentsProposal Forms
Latest STC Updates
Recently added modifications
  • CM075: Clarification on TO Final Sums Definition
  • PM0117 Annual Charge Setting - data submission flexibility
  • PM0116 Amendments to STCP18-1 'Connection and...
Next events
  • STC Panel Meeting - 24 February 2021
  • STC Panel Meeting - 31 March 2021
  • STC Panel Meeting - 28 April 2021
Modification Tracker

Modification Tracker

6 January 2020

Our Modification Tracker gives you the very latest detail on current modifications for each of the four codes. It includes the purpose of the modification and the stakeholders it affects, as well as Panel comments on prioritisation, and where it is in the review process.

This Modification Tracker will be published on a monthly basis on the 7th calendar day of the month or the next working day where the 7th is a non-working day.

Download the tracker

Standing Groups

21 June 2017

Standing groups give interested industry people the opportunity to discuss issues relating to electricity codes in more detail. Issues could relate to one or more of the codes, including the STC.

FInd out more

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