GC0183 – Grid Code (GC) changes
- Publication type:
- Code modification
- Publication date:
- Topic:
- National Energy System Operator (NESO),
- Energy codes
- Subtopic:
- Grid code
Outcome of changes GC0183, Generator and Interconnector Availability During a Severe Space Weather Event.
Details of outcome
We have decided to approve changes to Grid Code modification GC0183. This amendment introduces a requirement for Generators, Interconnector Owners, and Restoration Contractors to issue a ‘Space Weather Outage Declaration’.
Start date
4 December 2025
Code modification description
GC0183 introduces changes to the Grid Code to obligate Generators and Interconnector Owners to notify NESO of their intended position in the event of severe space weather.
GC0183 was raised by NESO on 09 July 2025 with a request for Urgent treatment. On 17 July 2025, the Grid Code Review Panel considered the Proposal and unanimously agreed that the Proposal should be treated as Urgent. We approved the request for Urgency on 25 July 2025.
The Proposal seeks to amend the Grid Code by introducing an obligation for Generators, Interconnector Owners, and Restoration Contractors to issue a ‘Space Weather Outage Declaration’ to NESO.