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Connection and Use of System Code (CUSC)
The Connection and Use of System Code is the contractual framework for connecting to and using the National Electricity Transmission System (NETS).
As the code administrator for the CUSC, we maintain the code and oversee any proposed changes to it. All changes have to be reviewed by the CUSC modifications Panel and approved by the Panel, or by Ofgem.
If you’re interested in becoming a CUSC party, you can find out more by visiting our ‘connections’ pages.
For more information about the code, please contact cusc.team@nationalgrideso.com
You can subscribe to the CUSC mailing list here.
Latest CUSC Updates
Recently Added Modifications
- CMP360 'Aligning Section 14 of the CUSC ‘Balancing Services Use of System Charg…
- CMP358 & CMP359 'Implementation of the Small Generation Discount into the CUSC …
- CMP357 'To improve the accuracy of the TNUoS Locational Onshore Security Factor…
- CMP355 & CMP356 'Updating the Indexation methodology used in TNUoS and Transmis…
- CMP354 'Capacity Allocation and Congestion Management Regulation (CACM) cost sh…
Next Events
- 26-01-21 to 16-02-21: CMP330 Workgroup Consultation
- 01-02-21 to 19-02-21: CMP360 Code Administrator Consultation
- 01-02-21 to 22-02-21: CMP326 Workgroup Consultation
- 04-02-21: TCMF
- 10-02-21: CMP328 Workgroup 4
- 11-02-21: CUSC - New Modification Proposal Submission Date
- 16-02-21: CMP308 Workgroup 11
- 18-02-21: CUSC - Panel Papers Published to Industry
- 26-02-21: CUSC Panel Meeting
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.
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 CUSC.