Panel & Ofgem Approved Code Artefacts

The following Code Panels have approved the MHHS Code drafting under their respective Significant Code Review (SCR) Modifications:

• Balancing & Settlement Code (BSC)
• Retail Energy Code (REC)
• Distribution Connection and Use of System Agreement (DCUSA) 

On 26 November 2024, Ofgem approved these Modifications, meeting Milestone 7 (M7) and you can read more about the decisions via the links below:

• BSC Ofgem decision
• REC Ofgem decision
• DCUSA Ofgem decision

These Code Artefacts will take effect at Milestone 8 (M8) in September 2025.

You can find the relevant SCR Modification pages via the following links:

P478: Implementation of MHHS Arrangements 

Contact: bsc.change@elexon.co.uk 

R0209: Implementation of MHHS Arrangements

Contact: enquiries@recmanager.co.uk 

DCP445: Implementation of MHHS Arrangements

Contact: dcusa@electralink.co.uk 

Copies of the Panel approved MHHS Code Artefacts are available below for completeness.

The master versions are now owned and maintained by the respective Codes, and any queries or comments should be addressed to the respective Code mailbox/helpdesk.

Energy Market Data Specification (EMDS)

Included in these Modifications was EMDS vMHHS 1.1 which was based on MHHS Design Interim Release (IR) 8.1.

EMDS vMHHS 1.2 was published on Friday 28 February 2025, which corrects errors identified in the previous version. It has also been updated to reflect MHHS Design IR8.2 to IR8.8 and you can view this in the Approved Cross-Code Data Specification library below.  

The changes in EMDS vMHHS 1.2 are documented in the M8 Change Control Log, which you can view on the Pre-M8 Change page of the Collaboration Base. This is a working draft, and participants should continue to use the MHHS Design Artefacts for their Design, Build and Testing. Further iterations of the EMDS may be provided if additional issues are identified, there are further MHHS Design Artefact updates or there are clarifications on the interpretation of the Design. 

You can view further information on how to identify Data Items within EMDS vMHHS 1.2 that are being updated for MHHS in the EMDS vMHHS 1.2 Guidance Notes document published in the Approved Cross-Code Data Specification library below.