Grid Code Modifications

Find a list of all modifications made to the Grid Code.

The following Grid Code modifications include any updates made in version 6 and any updates made after version 6 was issued.

If you would like to make a modification to the Grid Code, complete the form linked below and send it to:

Grid Code Modification Form (Doc, 45KB)

MPID	Title	Status	Effective Date	Grid Code Version
326	MPID326_Safety_Rules_Definition_GridCodeModificationProposal (PDF, 0.15MB)
325	MPID325_PPM-Intro_GridCodeModificationProposal (PDF, 0.19MB)
322	MPID322_Mod_Proposal_Update_of_definitions_for_RfG_Non_RfG_HVDC_Non_HVDC_DCC_and_Non_DCC_Units_Revised (PDF, 0.28MB)
321	MPID 321 IOS Reference Correction (PDF, 0.16MB)	MPID 321 Recommendation (PDF, 0.16MB)
320	MPID 320 NPDR (PDF, 0.21MB)	MPID 320 Recommendation (PDF, 0.21MB)
318	MPID318_ESPS_Phase2_Greenline_GCV14.2_Revised (PDF, 4.13MB)MPID318_ESPS_Phase2_GridCodeModLocationsSeptGCRP (XLSX, 0.04MB)MPID318_ESPS_Phase2_Modification_Proposal_Revised (PDF, 0.18MB)MPID318_ESPS_Phase2_Redline_GCV14.2_Revised (PDF, 4.16MB)
317	MPID317_ModificationProposal_Signals_and_indications_required_from_Users_Revised (PDF, 0.29MB)
315	MPID 315 House-keeping PPM Clauses (PDF, 0.24MB)	MPID 315 Recommendation Paper (PDF, 0.24MB)	CRU Approval - 15/12/2023 (PDF, 0.04MB)	14
314	MPID 314 PPM RfG Reference Correction (PDF, 0.16MB)	MPID 314 Recommendation Paper (PDF, 0.16MB)	CRU Approval - 15/12/2023 (PDF, 0.04MB)	13
313	MPID 313 House-keeping OC Clauses (PDF, 0.23MB)	MPID 313 Recommendation Paper (PDF, 0.23MB)	CRU Approval - 15/12/2023 (PDF, 0.04MB)	13
312	MPID 312 Removal of IOP (PDF, 0.18MB)	MPID 312 Recommendation Paper (PDF, 0.19MB)	CRU Approval - 12/07/24 (PDF, 0.09MB)	14
311	MPID 311 Housekeeping Clauses (PDF, 0.23MB)	MPID 311 Recommendation Paper (PDF, 0.24MB)	CRU Approval - 22/09/2023 (PDF, 0.04MB)	13
310	MPID 310 Housekeeping Definitions (PDF, 0.18MB)	MPID 310 Recommendation Paper (PDF, 0.18MB)	CRU Approval - 22/09/2023 (PDF, 0.04MB)	13
309	MPID 309 CC Requirements for PPMs (PDF, 0.26MB)	MPID 309 Recommendation Paper (PDF, 0.26MB)	CRU Approval - 25/09/2023 (PDF, 0.04MB)	13
308	MPID 308 Housekeeping Clauses (PDF, 0.17MB)	MPID 308 Recommendation Paper (PDF, 0.17MB)	CRU Approval - 22/09/2023 (PDF, 0.04MB)	13
307	MPID 307 Housekeeping Definitions (PDF, 0.17MB)	MPID 307 Recommendation Paper (PDF, 0.17MB)	CRU Approval - 22/09/2023 (PDF, 0.04MB)	13
306	MPID 306 Individual Demand Site V2 (PDF, 0.16MB)	MPID 306 Recommendation Paper (PDF, 0.16MB)	CRU Approval - 22/09/2023 (PDF, 0.04MB)	13
305	MPID 305 Offshore PPM Incorporation (PDF, 0.17MB) Red-line version (proposal) (PDF, 4.01MB) Green-line version (proposal) (PDF, 4.00MB) Locations Document (proposal) (XLSX, 0.03MB)	MPID 305 Recommendation Paper (PDF, 0.20MB)MPID 305 Red Line Version Recommendation (PDF, 3.99MB)MPID 305 Green Line Version Recommendation (PDF, 3.98MB)Locations Document (recommendation) (XLSX, 0.02MB)	CRU Approval 19/02/2024 (PDF, 0.09MB)	14
304	MPID 304 Incorporation ESPS Implementation Note RevisionMay23 (PDF, 0.17MB)MPID 304 ESPS Red Line Version RevisionMay23 (PDF, 4.03MB)MPID 304 ESPS Green Line Version RevisionMay23 (PDF, 4.02MB)	MPID 304 Recommendation Paper (PDF, 0.17MB)MPID 304 Red Line Version Recommendation (PDF, 4.03MB)MPID 304 Green Line Version Recommendation (PDF, 4.02MB)	CRU Approval - 25/09/2023 (PDF, 0.04MB)	13
302	MPID 302 Correction 220kVGraph Remote End Interconnector Converter Station (PDF, 0.38MB)	MPID 302 Recommendation Paper (PDF, 0.38MB)	CRU Approval - 25/09/2023 (PDF, 0.04MB)	13
301	MPID 301 NCER SOGL Alert States (PDF, 0.34MB)	MPID 301 Recommendation Paper (PDF, 0.35MB)	CRU Approval - 25/09/2023 (PDF, 0.04MB)	13
229(a)	MPID 229(a) RoCoF Implementation MPID229 (PDF, 0.27MB)	MPID 229(a) Recommendation Paper (PDF, 0.30MB)	09/08/2023 - CRU Approval (PDF, 0.04MB)	13
300	MPID 300 Solar PV Signal Requirements (PDF, 0.21MB)	MPID 300 Recommendation Paper (PDF, 0.21MB)	09/11/2022 – CRU Approval (PDF, 0.04MB)	12
299	MPID 299 FERA Reduction of Aggregator Limit to 1 MW (PDF, 0.17MB)	MPID 299 Recommendation Paper (PDF, 0.20MB)
298	MPID 298 GridCode v9 Housekeeping (PDF, 0.19MB)	MPID 298 Recommendation Paper (PDF, 0.20MB)	09/11/2022 – CRU Approval (PDF, 0.04MB)	12
297	MPID 297 Correction PPM RfG Non RfG Frequency Periods (PDF, 0.23MB)	MPID 297 Recommendation Paper (PDF, 0.23MB)	09/11/2022 – CRU Approval (PDF, 0.04MB)	12
296	MPID 296 Correction of Wind Powered Controllable PPMs (PDF, 0.19MB)	MPID 296 Recommendation Paper (PDF, 0.20MB)	01/04/2022 – CRU Approval (PDF, 0.08MB)	11
278	MPID 278 Correction Reactive Power Capability Requirements (Revised) (PDF, 0.18MB)	MPID 278 Recommendation Paper (PDF, 0.18MB)	17/12/2021 - CRU Approval (PDF, 0.09MB)	11
294	MPID 294 Align the Grid Code to the GCRP Constitution (PDF, 0.23MB)	MPID 294 Recommendation Paper (PDF, 0.19MB)	09/11/2022 – CRU Approval (PDF, 0.04MB)	12
293	MPID 293 DRAI DSU Maximum Down Time (PDF, 0.25MB)	MPID 293 Recommendation Paper (PDF, 0.30MB)
292	MPID 292 Incorporation HVDC Operational Notification Process DC-connected PPMs (PDF, 0.20MB)	MPID 292 Recommendation Paper (PDF, 0.21MB)	17/12/2021 - CRU Approval (PDF, 0.09MB)	11
291	MPID 291 Incorporation HVDC Operational Notification Process Interconnectors (PDF, 0.20MB)	MPID 291 Recommendation Paper (PDF, 0.21MB)	17/12/2021 - CRU Approval (PDF, 0.09MB)	11
290	MPID 290 Incorporation HVDC Derogation Process (PDF, 0.23MB)	MPID 290 Recommendation Paper (PDF, 0.22MB)	17/12/2021 - CRU Approval (PDF, 0.09MB)	11
289	MPID 289 Incorporation HVDC Parameters (PDF, 0.23MB)MPID 289 GC10 HVDC Article Incorporation Locations (PDF, 0.20MB)MPID 289 GC10 Red Line Version (PDF, 4.59MB)MPID 289 GC10 Green Line Version (PDF, 4.49MB)Demarcation and Future Harmonisation Methodology (PDF, 0.52MB)	MPID 289 Recommendation Paper (PDF, 0.19MB)	17/12/2021 - CRU Approval (PDF, 0.09MB)	11
288	MPID 288_BlackStart Test Intervals Emergency Restoration Network Code (PDF, 0.29MB)	MPID 288 Recommendation (PDF, 0.17MB)	18/05/2021 - CRU Approval (PDF, 0.08MB)	10
287	MPID 287_Meteorological Signal Requirements (PDF, 0.17MB)	MPID 287 Recommendation Paper (PDF, 0.18MB)	18/05/2021 - CRU Approval (PDF, 0.09MB)	10
286	MPID 286 Correction of Voltage Graphs110kV 220kV Systems Transmission (PDF, 0.53MB)	MPID 286 Recommendation Paper (PDF, 0.29MB)	18/05/2021 - CRU Approval (PDF, 0.09MB)	10
285	MPID 285 Correction of RfG Derogation Process Form References (PDF, 0.21MB)	MPID 285 Recommendation Paper (PDF, 0.14MB)	18/05/2021 - CRU Approval (PDF, 0.08MB)	10
284	MPID 284 PC.A8.2 and PC.A8.5 Simulation Compliance (PDF, 0.34MB)	MPID 284 Recommendation Paper (PDF, 0.34MB)	6/11/2020 – CRU Approval (PDF, 0.08MB)	9
283	MPID 283 Correction of PPM1.3.2 List (PDF, 0.17MB)	MPID 283 Recommendation Paper (PDF, 0.33MB)	6/11/2020 – CRU Approval (PDF, 0.08MB)	9
282	MPID 282 Incorporation of DCC Operational Notification Process (PDF, 0.34MB)	MPID 282 Recommendation Paper (PDF, 0.43MB)	6/11/2020 – CRU Approval (PDF, 0.08MB)	9
281	MPID 281 Incorporation of DCC Derogation Process (PDF, 0.30MB)	MPID 281 Recommendation Paper (PDF, 0.38MB)	6/11/2020 – CRU Approval (PDF, 0.08MB)	9
280	MPID 280 Correction of Duplication OC.9.4.1 (PDF, 0.33MB)	MPID 280 Recommendation Paper (PDF, 0.33MB)	6/11/2020 – CRU Approval (PDF, 0.08MB)	9
279	MPID 279 Correction of Connection Voltage Graphs PPM1.6.3.4 (PDF, 0.51MB)	MPID 279 Recommendation Paper (PDF, 0.50MB)	6/11/2020 – CRU Approval (PDF, 0.09MB)	9
278	MPID 2778 MPID 278 Correction of Reactive Power CC.7.3.6.1 (PDF, 0.34MB)	MPID 278 Recommendation Paper - WITHDRAWN (PDF, 0.34MB)
277	MPID 277 Clarification of PPM FRT Requirements PPM1.4.2(c) (PDF, 0.48MB)	The TSO came to the conclusion that no modification was required to the Grid Code. It was agreed with IWEA that the TSO will issue a Grid Code clarification note along with guiding principles to be used when assessing Grid Code compliance.
276 (a) revised	MPID 276 (a) Revised Incorporation of the approved Network Demand Connection Code (PDF, 0.27MB)	MPID 276 (a) Revised Recommendation Paper (PDF, 0.36MB)	6/11/2020 – CRU Approval (PDF, 0.07MB)	9
276	Incorporation of: Approved European Network Demand Connection Code (DCC) \| Approved European Network Code Requirements for Generators – Operational Notification Procedure & Derogation Process \| Housekeeping Modification MPID 276 Proposal Papers (ZIP, 8.02MB)	MPID 276 Recommendation Papers (ZIP, 8.66MB)	12/03/2020 – MPID 276 (a) - decision deferred by the CRU. 12/03/2020 – Partial approval from CRU for MPID 276 (b) (c) and (d). (PDF, 0.13MB)	8.1
275	Proposal_MPID275_Integration_RfG_GridCode (ZIP, 15.13MB)Proposal_MPID275_GC8_RfG_ArticleIncorporationLocations (ZIP, 15.13MB)Proposal_DemarcationAndFutureHarmonisationMethodology (ZIP, 15.13MB)Proposal_MPID275_GC8_RedLineVersion (ZIP, 15.13MB)Proposal_MPID275_GC8_GreenLineVersion (ZIP, 15.13MB)	Recommendation_MPID275_Integration_RfG_GridCode (ZIP, 15.13MB)Recommendation_MPID275_GC8_RfG_ArticleIncorporationLocations (ZIP, 15.13MB)Recommendation_MPID275_GC8_RedLineVersion (ZIP, 15.13MB)Recommendation_MPID275_GC8_GreenLineVersion (ZIP, 15.13MB)	14/06/2019 - CRU Approval (ZIP, 15.13MB)	8
274	MPID 274 Housekeeping – Transmission System Security Planning Standards (PDF, 0.33MB)	MPID 274 Recommendation Paper (PDF, 0.29MB)	06/11/2018 – CRU Approval (PDF, 0.04MB)	7
273	MPID 273 Met Mast Proposal (PDF, 0.36MB)	MPID 273 Recommendation Paper (PDF, 0.38MB)	06/11/2018 – CRU Approval (PDF, 0.04MB)	7
272	MPID 272 Clarification to Grid Connected Transformer Neutral Earthing Requirements (PDF, 0.36MB)	MPID 272 Recommendation Paper (PDF, 0.28MB)	30/04/2018 – CRU Approval (PDF, 0.02MB)	7
271 (a)	PID271 (a) Scheduling And Dispatch For ISEM Revised Version SDC.4.10 (c) (PDF, 0.20MB)	MPID 271(a) Recommendation Paper (PDF, 0.20MB)	Cutover Time - CRU Approval (PPTX, 1.76MB)	7
271	MPID 271 Modification Proposal Cover Letter (PDF, 0.26MB)MPID 271 Proposed Modifications Required for I-SEM - Ireland Grid Code (PDF, 0.29MB)MPID 271 Red Line Version of Proposed Modifications (PDF, 1.35MB)MPID 271 Green Line Version of Proposed Modifications (PDF, 1.26MB)	Consultation response period is closed	Cutover Time - CRU Approval (PPTX, 1.76MB)	7
270	Proposed Housekeeping Modification WFPS 1.6.2.5 (PDF, 0.72MB)	MPID 270 Recommendation Paper (PDF, 0.72MB)	04/05/2017 - CER Approval (PDF, 0.02MB)	7
269	MPID 269 Power Park Proposal (PDF, 1.08MB)	MPID 269 Power Park Module Recommendation Paper (PDF, 2.03MB)	10/10/2016 - CER Approval (PDF, 0.03MB)	7
268	MPID 268 Outturn Availability Proposal (PDF, 0.17MB)MPID 268 Supplementary Note (PDF, 0.08MB)	MPID 268 Outturn Availability Recommendation Paper (PDF, 0.28MB)	10/10/2016 - CER Approval (PDF, 0.02MB)
239	MPID 239 Dynamic Models Proposal (PDF, 0.62MB)TSO Position Paper on Retrospective Application of MPID 239 (PDF, 0.04MB)Dynamic Model Validation Guidelines Draft (PDF, 0.26MB)Dynamic Models Specifications for Users (PDF, 0.07MB)Note on Electromagnetic Transient Models (PDF, 0.05MB)	MPID 239 Dynamic Models Recommendation Paper (PDF, 0.88MB)MPID 239 Dynamic Models Recommendation Supporting Paper (PDF, 0.52MB)	01/06/2016 - CER Approval (PDF, 0.02MB)	7
267	MPID 267 Failure to Follow Notice to Synchronise Definition Proposal (PDF, 0.07MB)	MPID 267 Recommendation Paper (PDF, 0.12MB)	22/03/16 - CER Approval (PDF, 0.02MB)	7
266	MPID 266 Acronyms Proposal‌‌‌ (PDF, 0.13MB)	MPID 266 Recommendation Paper (PDF, 0.18MB)	28/09/15 - CER Approval (PDF, 0.16MB)	7
265	MPID 265 Reactive Power‌‌ (PDF, 0.11MB)	ON HOLD, Proposed Modification 11 February 2015, Proposed Modification 12 November 2014
264	MPID 264 Power Quality Harmonics‌ (PDF, 0.33MB)	MPID 264 Power Quality Recommendation Paper (PDF, 0.41MB)	28/09/15 - CER Approval (PDF, 0.16MB)	7
263	Grid Code Constitution and Rules Version 6‌ (DOCX, 0.05MB)	Proposed Modification 11 February 2015, Proposed Modification 12 November 2014 Constitution and Rules of the Grid Code Review Panel (PDF, 0.18MB)
262	MPID 262 WFPS Curve 2‌ (PDF, 0.23MB)	ON HOLD, ‌Proposed Modification 11 February 2015, Proposed Modification 12 November 2014
261	MPID 261 Connection Offers (PDF, 0.17MB)	MPID 261 Connections Offers Recommendation Paper (PDF, 0.21MB)	28/09/15 - CER Approval (PDF, 0.16MB)	7
260	Housekeeping of WFPS clause WFPS1.5.4.1‌‌‌ (PDF, 0.08MB)	Recommendation Paper - APPROVED (PDF, 0.13MB)	19/01/15 - CER Approval (PDF, 0.21MB)	6
259	Definition Re-ordering‌‌‌ (PDF, 0.07MB)	Recommendation Paper - APPROVED (PDF, 0.12MB)	19/01/15 - CER Approval (PDF, 0.21MB)	6
258	DSU Signal List‌‌‌ (PDF, 0.19MB)	APPROVED	19/01/15 - CER Approval (PDF, 0.21MB)	6
257	MPID 257 DSU Performance Monitoring (GCRP 40) (PDF, 0.15MB)DSU Performance Monitoring‌‌‌ (GCRP 39) (PDF, 0.15MB)	MPID 257 DSU Performance Monitoring of DSU Dispatch Instructions Recommendation (PDF, 0.29MB)	25/09/15 - CER Approval (PDF, 0.16MB)	7
256	DSU Notice Time‌‌‌ (PDF, 0.15MB)	Recommendation Paper - APPROVED (PDF, 0.20MB)	19/01/15 - CER Approval (PDF, 0.21MB)	6
255	DSU Housekeeping‌‌‌ (PDF, 0.18MB)	MPID 255 Recommendation Paper- APPROVED (PDF, 0.20MB)	19/01/15 - CER Approval (PDF, 0.21MB)	6
254	MPID 254 DSU Frequency Requirements (GCRP 40)‌‌‌‌ (PDF, 0.23MB)DSU Frequency Requirements‌‌‌ (GCRP 39) (PDF, 0.29MB)	MPID 254 DSU Frequency Requirements Recommendation Paper (PDF, 0.25MB)	28/09/15 - CER Approval (PDF, 0.16MB)	7
253	DSU Application‌‌‌ (PDF, 0.16MB)	Recommendation Paper - APPROVED (PDF, 0.18MB)	19/01/15 - CER Approval (PDF, 0.21MB)	6
252	MPID 252 POR Definition‌ (PDF, 0.07MB)	MPID 252 Recommendation Paper (PDF, 0.13MB)	28/09/15 - CER Approval (PDF, 0.16MB)	7
251	WFPS Active Power Control‌‌‌ (PDF, 0.16MB)	Recommendation Paper - APPROVED (PDF, 0.13MB)	19/01/15 - CER Approval (PDF, 0.13MB)	6
250	WFPS Signal Lists‌‌‌ (PDF, 0.24MB)	MPID 250 Recommendation Paper (PDF, 0.29MB)	28/09/15 - CER Approval (PDF, 0.16MB)	7
249	Interconnector AGC‌‌‌ (PDF, 0.08MB)	Recommendation Paper - APPROVED (PDF, 0.14MB)	19/01/15 - CER Approval (PDF, 0.13MB)	6
248	WFPS Voltage Regulation‌‌‌ (PDF, 0.22MB)	Recommendation Paper - APPROVED (PDF, 0.15MB)	19/01/15 - CER Approval (PDF, 0.13MB)	6
247	DS3 Clarification Post Fault Active Power Recovery‌‌ (PDF, 0.06MB)	Recommendation Paper - APPROVED (PDF, 0.08MB)	19/01/15 - CER Approval (PDF, 0.13MB)	6
246	Housekeeping DS3 Reactive Power‌ (PDF, 0.08MB)	Recommendation Paper‌ - APPROVED (PDF, 0.08MB)	24/02/14 - CER Approval (PDF, 0.02MB)	6
245	Housekeeping DS3 Frequency Response‌ (PDF, 0.16MB)	MPID245 Recommendation Paper - APPROVED (PDF, 0.17MB)	15/04/14	6
244	Housekeeping of Clause OC10.4.5.2‌ (PDF, 0.05MB)	Recommendation Paper‌ - APPROVED (PDF, 0.04MB)	24/02/14 - CER Approval (PDF, 0.02MB)	6
229	RoCof Definition Proposal (PDF, 0.07MB)	Recommendation Paper APPROVED IN PRINCIPLE (PDF, 0.36MB)RoCof Definition Proposal (PDF, 0.07MB)Rate of Change Frequency Decision Paper	Approved in Principle – 04/04/2014
223	MPID 223 Fail to Sync November 2014 (PDF, 0.16MB)	MPID 223 Fail to Sync Recommendation Paper (PDF, 0.21MB)ESB GWN Letter to CER on MPID 223 Fail to Sync (PDF, 0.59MB)	28/09/15 – CER Approval (PDF, 0.59MB)	7

Grid Code Modifications

MPID

Title

Status

Effective Date

Grid Code Version