Market-wide Half Hourly Settlement (MHHS) Working Groups

Here you can find the outputs of three industry working groups which Elexon is chairing and providing with technical leadership to support Ofgem’s Significant Code Review (SCR) on Electricity Settlement Reform.

What MHHS working groups are Elexon leading?

As part of Ofgem’s SCR, Elexon is leading the following three working groups which all report to Ofgem. Ofgem sets the groups’ membership and Terms of Reference.

  • Design Working Group (DWG): The DWG ran from 2017 to 2019 and is now stood down. It designed the Target Operating Model (TOM) for MHHS, as well as the high-level approach for transitioning from the current Settlement arrangements to the TOM. We submitted the DWG’s final report to Ofgem in August 2019. Ofgem gave its preliminary approval to the DWG’s TOM and transition approach in October 2019.
  • Code Change and Development Group (CCDG): The CCDG has been meeting since December 2019. It is developing the DWG’s TOM design and transition approach in more detail. It will also identify, and oversee drafting of, the changes needed to Industry Codes and subsidiary documents to enable the TOM.
  • Architecture Working Group (AWG): The AWG has also been meeting since December 2019. It is developing the reference architecture required to enable the DWG’s TOM. This reference architecture will set the framework for subsequent IT system design.

The diagram below shows the timing of the CCDG’s and AWG’s different consultations and reports.

How do these groups fit into Ofgem’s SCR process?

Development of the TOM forms one of several work streams in Ofgem’s wider SCR. Ofgem’s other parallel SCR work streams include:

  • Related policy decisions (on access to Half Hourly data for Settlement purposes and on Supplier Agent functions)
  • Consideration of consumer impacts
  • Development of the business case for MHHS (including Ofgem’s recent Draft Impact Assessment Consultation)

Ofgem will bring the outputs of all the SCR work streams together in its Full Business Case decision on how and when to proceed with MHHS. Ofgem will make the final decision on the TOM and transition approach. The CCDG and AWG can only make recommendations to Ofgem.

Following the CCDG’s final report, Ofgem will also make the necessary changes to licences and Industry Codes, which will not follow the normal Code change processes.

What’s new?

On 17 December 2020, we issued the CCDG’s consultation on its detailed Target Operating Model design and its identified impacts on Industry Codes. The consultation runs until 26 January 2021. We are also holding a webinar on 13 January 2021 to talk through the consultation and answer any questions.


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