Our response to coronavirus

Find out how we're working to keep Great Britain’s lights on reliably throughout the outbreak

CMP328: Connections Triggering Distribution Impact Assessment

There are cases where Transmission connections can have an impact on the Distribution system. An example of this is the connection of generation to the tertiary winding of the Grid Supply Point (GSP). In these cases, the Distribution Network Operator (DNO) must carry out an impact assessment to identify any impact on the Distribution system and any operational restrictions that may be required, National Grid Electricity System Operator (NGESO) propose to utilise the Third Party Works process to facilitate this process; however, there are significant shortfalls in applying the Third Party Works process in this scenario.

This modification proposes to put in place an appropriate process to be utilised when any connection triggers a Distribution impact assessment. Ensuring the process in place for such connections, best reflects the necessary contractual relationship of parties involved.

Modification status: Current - New modification

Last updated: 14 May 2020

Code Administrator Contact: Paul J Mullen - [email protected]

Governance Route: Standard 


* Medium: Distribution Network Operators (DNO) and NGESO.

* Low: Transmission Users. This proposed Connection and Use of System Code (CUSC) Modification would only affect those who connect in the future. It will have no impact on those already connected.


Proposal documents

Workgroup Terms of Reference

Workgroup meetings and summary papers

Sorry, no documents found.

Workgroup consultation

Sorry, no documents found.

Code administrator consultation

Sorry, no documents found.

Draft/Final modification report

Sorry, no documents found.

Authority decision

Sorry, no documents found.