Design Working Group preferred TOM report

Publication date
15th February 2019
Information type
Policy area

Ofgem has now received the Design Working Group (DWG) Report on their preferred Target Operating Model (TOM) for Market-wide Half-Hourly Settlement (MHHS). The ELEXON-chaired DWG have come to the preferred TOM following the development of the five Skeleton TOMs, which were set out at the end of Stage 1.

During Stage 2, the DWG developed the more detailed service requirements for the TOMs, evaluated the different TOMs in light of Ofgem’s Design Principles and policy steers, and chosen a preferred TOM. This work was supported by four workgroups reporting to the DWG. 

The TOM Report, which is available below, is in four parts:

  • The Main Report setting out the DWG recommendations to Ofgem on the preferred TOM
  • Attachment A: Detailed TOM Service and Data requirements
  • Attachment B: DWG’s development of the TOM
  • Attachment C: Risks, Assumptions, Issues and Dependencies.

ELEXON will consult on the preferred TOM in February 2019, and the DWG will then develop a transition approach for moving from the current Settlement arrangements to the preferred TOM. The DWG will consult on this and deliver the final Stage 2 report to Ofgem during summer 2019, in time to inform our decision on the Full Business Case and on when and how to implement MHHS.