Elexon’s response to National Grid ESO GC0156 Workgroup Consultation

Elexon have responded to the Workgroup Consultation for Grid Code Modification GC0156 ‘Facilitating the Implementation of the Electricity System Restoration Standard’.

In our response we highlight the likely impacts of GC0156 on the BSC’s Black Start processes, which will need further assessment and development as part of a BSC Modification Proposal. We also set out our concerns over the proposed GC0156 implementation approach and include some questions on the Grid Code legal text.

Finally, we welcome NGESO’s continued engagement with us on the scope and timetable for any BSC Modification Proposal, including confirmation that we can close BSC Issue 100 ‘Assessing BSC Black Start processes to support NGESO’s Distributed ReStart project’.

Our response

The current, end-to-end, industry Black Start process includes:

  • Provisions in Operating Code (OC) 9 of the Grid Code (‘Contingency Planning’), which cover how electricity is restored across the Total System following a Black Start, and which define a Black Start as either a Total Shutdown or Partial Shutdown of the system;
  • Provisions in Balancing Code (BC) 2 of the Grid Code (‘Post Gate Closure Process’), which cover the emergency actions and instructions that NGESO may use during the Black Start restoration process under OC9; and
  • Provisions in Section G of the BSC (‘Contingencies’) and BSC Procedure 201 (‘Black Start and Fuel Security Contingency Provisions and Claims Processes’), which cover:
    • When and how normal BSC market operations are suspended and resumed following NGESO’s notification that a Black Start (either a Total Shutdown or Partial Shutdown) has occurred under the Grid Code; and
    • The processing and payment of BSC Black Start compensation claims for any BSC Parties to whom NGESO has given specific types of Grid Code instructions, during the Black Start restoration process, under OC9 and BC2.

The Grid Code and BSC provisions cross-reference each other, both on the process steps to be taken and in determining which Black Start instructions under the Grid Code are eligible for BSC compensation. We have therefore focused our review of the GC0156 legal text on the changes to BC2 and OC9.

Black Starts are emergency black-out events that are likely to significantly disrupt normal communication channels. It is therefore important that all affected industry parties have certainty (in advance of any Black Start event actually occurring) of the contingency rules that will apply during a Black Start, and that these rules work effectively as an end-to-end process across the Grid Code and BSC.

With this in mind, our response offers our comments on the following:

  1. The potential BSC impacts of GC0156 that will need further assessment and development by a Workgroup, as part of any related BSC Modification Proposal.
    Because of the interactions between the Grid Code and BSC processes, NGESO’s clarification of the intended BSC outcomes will be critical to support development and assessment of any necessary BSC changes. Our comments in this area are relevant to Consultation Question 26, which asks if any implications of GC0156 for stakeholders are unclear.
  2. The potential risks and issues for industry parties in the end-to-end Black Start process, which could be created by the proposed GC0156 implementation approach and legal text.
    We have concerns that the current GC0156 implementation approach may not enable alignment of implementation for the drafting to all impacted Industry Codes. This means that the changes to the Grid Code and BSC will come into effect at different points, potentially some months apart. This could result in inconsistent interpretation and application of the Black Start rules between different Codes if a Black Start occurs. As well as creating potential confusion over the rules during an emergency, this could have material consequences for BSC Parties if it affects their ability to bring claims for BSC Black Start compensation. These comments are relevant to Consultation Questions 2 and 17 on the GC0156 implementation approach and legal text.

We include our detailed comments in Appendix 1.

We understand that NGESO intends to raise a BSC Modification Proposal to support the outcomes of GC0156. We thank you for your discussions with us on this so far.

We welcome your continued engagement and clarification on the scope of the BSC Modification as you prepare to raise it.

We would also welcome NGESO’s confirmation as the Proposer of BSC Issue 100 that we can now close this Issue, which has been on hold for some time at NGESO’s request.

We understand that the scope of Issue 100 has been superseded by the GC0156 Workgroup discussions and therefore no longer reflects your latest thinking on the intended BSC changes.


Contact Information

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