Grid Code Modifications

You can raise a modification – or mod – when you want to propose a change to any part of the Grid Code

For more information, please contact [email protected]

Search for any current or concluded modifications by name or ID. You can sort mods by ID, name, status or date of update. Or filter according to status.

Modification Requests

Modification status
ID Name Status Last Updated Sort ascending Link to modification
GC0101 GC0101: EU Connection Codes GB Implementation – Mod 2 Implemented view
GC0100 GC0100: EU Connection Codes GB Implementation – Mod 1 Implemented view
GC0097 GC0097: Grid Code Processes Supporting TERRE Implemented view
GC0163 GC0163: GB Grid Forming (GBGF) - Removal of Virtual Impedance restriction Implemented view
GC0170 GC0170: Typographical and formatting updates following the implementation of GC0156: Facilitating the Implementation of the Electricity System Restoration Standard Implemented view
GC0022 GC0022: Frequency Response Concluded view
GC0023 GC0023: Protection Fault Clearance Times and Back-up Protection Concluded view
GC0028 GC0028: Constant Terminal Voltage Concluded view
GC0079 GC0079: Frequency Changes during Large Disturbances and their effect on the total system - Phase 1 & 2 Concluded view
GC0036 GC0036: Review of Harmonics Assessment Standards and Processes Concluded view

More about modifications

Modification Tracker

Our Tracker gives you the latest details on current code modifications including the purpose and the stakeholders it affects, as well as panel comments and where it is in the review process. It is published on the 7th (or next working day) of each month.

Raise a modification

If you're thinking about raising a modification, please get in touch with us. Our experts can give you advice on your Proposal, explain how the modification process works and help to answer any questions you may have. When we receive your Proposal, we'll check it through and work together to make sure it's easy to understand.

Calendar

Once you've been in touch and are ready to write your Proposal paper, send it to us by the monthly modification submission date which you can find on our Calendar.