Market-wide Half-Hourly Settlement (MHHS)

The main aim of the MHHS programme is to gain more timely insight into how much electricity is being used by consumers, and when, so that generators, suppliers and consumers can better understand, forecast and generate the volume of power the UK needs.

According to industry regulator Ofgem, this will then unlock "flexibility to support the transition to net zero" and "contribute to a more cost-effective electricity system, encouraging more flexible use of energy and helping consumers lower their bills."

You do not need to do anything prior to migration, as your supplier will initiate and complete the process. For business consumers, the impact of MHHS will depend on the types of meter you have and the products and services you currently receive.

All meters will be migrated as part of the industry-wide programme. Although meter replacement is not a requirement of MHHS, there may be exceptions whereby your supplier needs to conduct site visits and potentially exchange some meters. If this is the case, we will communicate with our impacted customers.

As part of the migration, your meters may end up in different segments:

Half-Hourly (HH) and Automated Meter Reading (AMR) meters will fall under the advanced segment, requiring an Advanced Data Service (ADS) and Metering Service (Advanced) (MSA) appointment.

Smart meters will need a Smart Data Service (SDS) and Metering Service (Smart) (MSS) appointment.

All non-domestic consumers are advised to appoint a metering service agent and data services agent, or you can allow your supplier to make the appointment on your behalf.

If we are your supplier and you do not have a Smart or Automated meter reading (AMR) meter and we continue to supply you using a traditional meter, we will keep using readings from yourself or agents working on our behalf, to ensure you continue to receive an accurate invoice.

To arrange a free meter exchange to either a Smart or AMR meter, please get in touch.

The MHHS timeline starts in April 2025 and runs through 2026. All industry parties will operate to different timelines within this period, as determined and co-ordinated by the overarching MHHS programme overseen by Ofgem.

Our migration schedule will be dependent on several factors, such as how many Meter Point Administration Numbers (MPANs) we are allowed to migrate in a day or the type of meter to be migrated.

When the time is right, we will get in touch with our customers to make sure they are kept up to date, and as this change will mean all meters will be migrated regardless of type, we will include a list of all the affected meters when appropriate.

If you are an npower Business Solutions (nBS) customer, please rest assured that we will contact you ahead of any changes.

For more information on MHHS and any key updates that will affect the energy sector and beyond, keep an eye out for our latest webinars, podcasts and videos.