By David Sheldrake, Global SVP of Sales360, POWWR
The need for energy meters in public sector buildings to adhere to the Market-wide Half Hourly Settlement (MHHS) rules set out by Ofgem is inching ever closer. It is important to remember that this migration is more than simply a technology upgrade; it signifies a move towards a more adaptable, responsive, and sustainable energy framework. By giving energy managers more control, promoting innovation, and encouraging collaboration, MHHS sets the stage for a future where achieving net zero is not just a goal, but a tangible reality.
Power back in the hands of the public sector
In many ways, this overhaul puts the power back in the hands of public sector businesses and provides greater awareness of energy consumption than ever before. Through the new breed of associated smart meters and the innovative time-of-use tariffs that will surely become available, energy managers will be able to make more informed decisions about when and how they use energy. This will not only help lower energy bills but lead to greater grid stability.
But it will in no way be an easy operation. Around 30 million meters will need to move over to the new MHHS Target Operating model, with 2.6 million of those being within businesses.
What is MHHS?
Market-wide Half Hourly Settlement (MHHS) is the new electricity market arrangements that will enable the flexibility to support transition to Net Zero. A shorter and more accurate Settlement timetable using Half Hourly meter readings for settled energy will support a cost-effective electricity system, encourage flexible use of energy and help lower bills. The MHHS Programme is an industry-led programme established to deliver the Target Operating Model and aims of the Electricity Settlement Reform Significant Code Review (SCR). This will see meters migrate to a new topline to comply with the changes. MPANs will migrate in phases by supplier. The suppliers are going through a qualification process, and this will determine when the MPAN is migrated.
Working harder to get smarter
Smart meters have been replacing traditional gas and electricity meters across the UK for almost a decade and a half. They make the energy system more flexible, boost efficiency, help in the move towards more renewable energy sources, and reduce energy consumption. Yet, despite these proven advantages though, moving customers to them has been tricky. According to the most recent data there are around 32.4 million smart and advanced meters in the UK, representing just 57% of all meters. That means that the energy industry is having to work doubly hard to convince the remaining 43% to rip and replace any meters that are not MHHS compatible.
A timeline for success
There are several significant milestones that have been set out by Ofgem. Here is a summary of those still to come so that you can plan accordingly:
September 2025 – The industry needs to be ready to change the Top Line Supply Numbers and migrate meters to be half hour ready. No physical meter changes are expected at this point, however terminology on bills will change. The migration of meters to half hour will be phased in two waves.
March 2026 – For the meters that are unable to be switched to half hour, suppliers will have to engage with consumers to make physical changes or replace meters to align to MHHS.
May 2027 – The date by which all eligible meters need to be switched.
July 2027 – Timeline complete and all meters can be half hour settled. All other electricity profile class (01-04) will no longer exist.
The benefits are numerous
The benefits of MHHS are numerous. Perhaps the most important, however, is that it will boost accuracy and stability. Through MHHS energy managers – and the industry as a whole – will have access to more granular data. This will lead to pricing with enhanced accuracy based upon true market conditions. The increased data will also likely lead to innovation in product offerings and a more stable grid.
Becoming active contributors
2025 will be see a ramp up in efforts to ensure both pricing and settlements become better aligned in the future. However, the overall roll-out will likely take another couple of years. During this time, there will be a teething period where public sector businesses and the energy industry alike need to become familiar with the required top line changes to the meters and what the new associated terminologies mean.
However, it is surely a price worth paying. The move to MHHS will ensure that energy managers can ensure that their businesses are no longer passive recipients of energy but become active contributors in a dynamic ecosystem. Becoming empowered to shape their own energy futures through participating in more dynamic pricing schemes and time-of-use tariffs.
This article appeared in the May 2025 issue of Energy Manager magazine. Subscribe here.