MHHS: Suppliers missing 2027 deadline face new customer restrictions

Although most of the work to overhaul the settlement process is happening behind the scenes on the supplier side, efforts are amping up as part of the Market-Wide Half-Hourly Settlement (MHHS).

The MHHS has already faced delays, with setbacks in System Integration Testing leading to a 6.5-month delay to the key milestones of the programme.

To ensure future deadlines are met, Elexon has announced that suppliers may be temporarily restricted from registering new customers if their customer MPANs are not migrated to the new MHHS systems by 7 May 2027.

What is MHHS?

Generators and suppliers trade electricity in half-hourly periods in the wholesale market. Settlement process reconciles the difference between how much suppliers purchase electricity, and how much their customers actually use.

Smart and advanced meters are becoming more widespread, recording actual consumption every half hour. The premise of Elexon’s MHHS programme is to create a system where the whole electricity market could be settled every half hour.

This is a monumental undertaking for the industry. For example, suppliers must migrate over 33 million MPANs – this is a unique 13-digit reference number which identifies an electricity supply point and shows on your electricity bill – onto a new system as part of the MHHS transition.

What is the latest?

There is an 18-month window for suppliers to migrate all their MPANs to the new arrangements, known as Milestone 15 of the MHHS programme, with a deadline of 7 May 2027.

This latest announcement is part of an Elexon incentive called P487, which seeks to ensure suppliers meet Milestone 15.

Once the last settlement date with MPANs in the existing arrangements has been reconciled, the incumbent settlement systems can be turned off.

A restriction imposed as part of P487 only applies to new registrations – it doesn’t affect existing customers or remove customers from a supplier.

What does MHHS mean for my organisation?

The message from Elexon is clear; MHHS must happen without delay.

Although suppliers are the drivers of the transition and face the consequences if the delays happen for reasons within their control, this latest announcement underlines the importance of ensuring you can take full advantage of the opportunities MHHS offers.

For instance, if your portfolio still has traditional meters, now is the time to get smart or advanced metering organised.

Once you have half-hourly data it’s time to look at your data collection. MHHS changes the way half-hourly metering data is collected, and businesses will need to appoint contracts for these new arrangements; choosing competitively priced services that offer added value in this new era of how electricity is used and accounted for is vital.

Moreover, MHHS marks a new era of energy visibility – stepping away from decades of industry practices reliant on estimations and periodic meter readings to real-time data.

How can Inspired help you?

Inspired’s metering experts can help you leverage MHHS, from readiness and data quality through to strategic insight and future-proofed operations.

Every portfolio is unique, but we can focus on a few key areas initially to reduce risk and realise benefits sooner:

• Audit and cleanse MPAN data: Ensure accurate linkage of MPANs to metering assets, including meter types, the ability of a smart meter and its associated communication hub to transmit and receive data, and configurations.
• Identify non-compliant meters: Flag and prioritise sites where smart or advanced meters are defunct, have issues in communicating and transmitting readings, or are incapable of delivering half-hourly data.
• Boost install/commissioning Quality Assurance: Ensure new installs meet the half-hourly-readiness standard (e.g., SMETS2, AMR with comms, etc).