We are publishing the latest information on Design Status so that you have easy access to an overview of progress on Design.

You can view the reports by clicking on the links below, with the most recent report at the top of the list.

The reports provide key updates on the Design Artefact Roadmap, Design Development Process, Success Criteria and Confidence Indicators, Target Outcomes and Participant Engagement.

MHHS Target Operating Model was defined by Ofgem

One of the key outputs of Ofgem’s initial electricity settlement reform Significant Code Review (SCR) was the development of a Target Operating Model (TOM) to deliver market-wide half-hourly settlement.

A series of working groups contributed to developing the TOM that Ofgem published in October 2019. These groups were a Design Working Group, a Code Change and Development Group, an Architecture Working Group and a Design Advisory Board.

Target Operating Model

MHHS Design will support the Target Operating Model across the industry

The MHHS Design is the foundation to the new ways of operating settlement. The MHHS Design will impact all parts of the industry, albeit in different ways, depending on the systems and processes that participants operate.

Ofgem has stated that the aim is to reach consensus on Design through engagement and consultation. If consensus cannot be reached, decisions will need to be taken in the best interest of the overall MHHS Programme objectives and plan.

Target Operating Model in context of MHHS Design

Design Consultation

The Design is being developed through real-time consultation with industry under the structure defined in Programme Governance.

Level 4 Working Groups and sub-groups have been established, as shown via the link below, with responsibility to review the Design Artefacts and work through gaps and issues to resolution.

Key decisions are made at the Level 3 Design Advisory Group (DAG) that reports to the Programme Steering Group (PSG).


Working Group structure

Design Artefacts and where to find them

Design Artefacts

Design Artefacts is the name for the suite of documents that form the design to support the new TOM. The Design Artefacts are logged into an architecture repository to assure for integrity, traceability, quality and to manage change control.

Business Process Diagrams

There are 26 Business Process diagrams to detail data collection and data processing, with swim-lanes to distinguish responsibilities for each element of the process.

Logical Interface Specifications

There are 37 logical Interface Specifications that describe data models and data catalogues for interfaces between systems.

Other Design Artefacts

There are a series of other Design Artefacts, varying in content, that include business requirements specifications and non-functional specifications (such as security, performance and scalability).

MHHS Programme Collaboration Base

As mature drafts become available, or are updated through review cycles, the documents are available in the MHHS Collaboration Base – simply navigate to the Design Documents Library.

As documents are often updated frequently, to ensure you are working from the latest version, please refer to and work from the documents published on the MHHS Collaboration Base.

Design consultation is in four tranches, with dependencies across the tranches

The Design Artefacts have been grouped into four logical groupings, as far as possible.

There are interdependencies between the Artefacts that cannot be avoided. This means that design changes in later tranches may require a review and update of Design Artefacts in an earlier tranche. Therefore approval of each tranche of documents can only be conditional i.e. conditional on there being no requirement to change the design due to review of a later Artefact.

Design Artefact Tranches

The core areas covered in each Tranche are listed below:

Design Artefact Tranche 1

  1. Core Registration Processes
  2. Sub-set of Registration Flows
  3. Core Registration Processes
  4. Sub-set of Registration Flows
  5. Load Shaping Service BPM, Requirements & Logical Interface Specifications

Design Artefact Tranche 2

  1. Change of Agent Impacted Processes and Interfaces
  2. Registration & Data Service Interfaces
  3. ECS Market Data Service Process & Requirements
  4. ECS Volume Allocations Services Process & Requirements

Design Artefact Tranche 3

  1. Smart Segment Requirements
  2. ECS Industry Standing Data Process & Requirements
  3. ECS Reporting Requirements
  4. Operational Choreography

Design Artefact Tranche 4

  1. Advanced Segment Requirements
  2. Unmetered Segment Requirements
  3. Registration Service Requirements
  4. Network Charging Process & Requirements
Design Artefact Tranche release for industry review & assurance

What is delivered once the Design is baselined

An enduring MHHS Design toolset is being developed using iServer 365 that will be the repository of the Design. The MHHS Design iServer solution allows design content to be presented in context and with supporting material.

iServer 365 has been chosen for the following reasons::

  1. works directly with Word, Excel, Visio, and SharePoint
  2. easy access through Software as a Service (SaaS) and browser with no technical set up
  3. viewer licenses are inexpensive and scalable
  4. supports integration with Azure DevOps used for requirements and test management
  5. supports baselined change control for informed impact assessment and audit

Access to the MHHS Design tool on iServer will be provided to participants from baseline through to post-Programme.


NEW! Design Newsletter

To supplement the Design Artefacts on the MHHS Portal we have developed a dedicated Design Newsletter with the first issue on 24 May. This will provide key updates, summaries and signposting to support you in delivering MHHS. The Design Newsletter will be issued every two weeks in line with the Design Status report.

The Clock will continue to be issued every Wednesday, covering all aspects of the MHHS Programme including key Design news.

If you already receive The Clock, you will automatically receive the Design Newsletter. You will have the option to unsubscribe at any time.

If you do not currently receive The Clock and wish to sign up to the Design Newsletter, simply complete the form below and the issues will automatically be delivered to your inbox.


Please fill in your details below to receive the Design Newsletter every fortnight.