Architecture Working Group recommendation on reference architecture to support MHHS

On 14 June 2021 we published the Architecture Working Group’s (AWG) recommendation to Ofgem that ‘event-driven’ reference architecture is developed to support Market-wide Half Hourly Settlement (MHHS) implementation. 

About the Architecture Working Group

The AWG is a group of industry IT experts, from Suppliers, Supplier Agents, and software support companies. It is one of the industry working groups that Elexon is currently leading to further develop the detailed business and system architectural elements of the MHHS Target Operating Model (TOM).

Why ‘event-driven’ architecture is needed for MHHS

The additional meter readings available from smart meters will result in a big increase in the volume and frequency of meter data that needs to be settled. Event-driven architecture will be able to respond to this more quickly, and at a much higher scale than is possible with the current arrangements.

The AWG ‘s recommendation to Ofgem

The AWG received 21 responses to the consultation on MHHS reference architecture. After carefully reviewing them, the AWG’s view is that the industry broadly supports the proposal.

The AWG is therefore not proposing any changes to its recommendation to Ofgem that event driven architecture is adopted to support the roll out of MHHS.

Next steps

Ofgem will consider the AWG’s recommendation and make a decision on whether to move ahead with the reference architecture. If this is the case, the next phase of work will be to determine a more detailed design, which would include technical and cost considerations.

AWG’s response to the feedback

Following the feedback, the AWG have acknowledged that the recommended architecture is at a conceptual level, and that the industry needs to see further detail.

The specifics of the architecture are yet to be designed, both from a business process and technical perspective.

The AWG agreed with respondents that the technical design of the architecture should use open technology, or open industry standards. This should enable a wider use of technology and available expertise to be sourced, giving more options to solution designs.

The group also noted other aspects of the feedback, including a potential overlap with the resource required for other industry change programmes (such as faster switching). The AWG has recommended to Ofgem that this is accounted for in planning.

On behalf of the AWG, Elexon thanks all the organisations that responded to the consultation and provided feedback.

The AWG consultation

Links to the consultation and other associated documents are on our website:

Consultation responses

Non-confidential responses to the AWG consultation are available to view here:


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