GC0155: Clarification of the Fault Ride Through Technical Requirements
What is being proposed
This modification is based on an alternative proposal (WAGCM2) to GC0151 ‘Grid Code Compliance with Fault Ride Through Requirements’. It aims to clarify the technical requirements for fault ride through capability set out in the Grid Code to improve consistency, accuracy and understanding and to help prevent non-compliance with the Grid Code.
Current status
The Panel met in January 2022 and agreed that it goes to a Workgroup. Workgroup meetings commenced on 10 February 2022. At the Workgroup meeting on 25 July 2022, ESO provided a plan for the additional work required by the workgroup and this revised timeline was approved at the July Grid Code Review Panel. A timeline extension was approved at the November Grid Code Review Panel. An updated timeline was approved by the June 2023 Grid Code Review Panel. A new timeline was presented to the August 2023 Grid Code Review Panel and was approved. A new timeline was approved at the January 2024 Grid Code Review Panel meeting. The next Workgroup meeting will be taking place on the 15 October 2024. An updated timeline will then be presented to the November Grid Code Review Panel for approval. The Workgroup planned for 15 October was delayed to 22/11/24 allow more time for actions to be completed. At this Workgroup, the Workgroup discussed the progress on the modification to date, and determined that a CBA is required for further analysis. At the February Grid Code Review Panel, the Panel agreed to having GC0155 split into two modifications. A new modification on the Temporary Over Voltage part of the modification is expected to be raised in March 2025. A timeline and Terms of Reference update were accepted at the March 2025 Panel.The next Workgroup is scheduled for early 2026. A timeline update will be presented to the January Panel. The timeline update was approved at the January Panel. 09/03/2026 The next Workgorup meeting is TBC.
Details
Timeline
Analysis
Grid Code modification GC0155 proposes to clarify fault ride through technical requirements for generators connecting to the transmission system. The modification has been in workgroup since February 2022 with multiple timeline extensions, now scheduled for early 2026. A cost-benefit analysis is required and the modification will be split into two parts, with a new modification on temporary over voltage expected in March 2025.
Why it matters
This addresses a compliance issue rather than changing substantive technical requirements — clarification typically benefits smaller developers who lack regulatory expertise to navigate ambiguous rules. The extended timeline suggests either technical complexity or industry disagreement over what constitutes appropriate fault ride through standards.
Key facts
- •Modification in workgroup since February 2022
- •Multiple timeline extensions
- •Cost-benefit analysis required
- •Split into two modifications
- •Next workgroup meeting early 2026