Half Hourly Meters

Businesses that have a peak load at any time during the day of more than 100kWh will have a half hour electricity meter.

What are Half Hourly Meters?

Half Hourly Meters (HHM) register how much electricity is used during each half hour of every day.  Typically they have a fixed or mobile phone connection to send data automatically back to the energy suppliers.  These readings provide more accurate data than manual ones and show how much energy a business is using at different times of the day, useful for energy efficiency initiatives.   Pricing can therefore be based on individual energy usage of a business rather than standard pricing.

During Installation or upgrades a competitive deal should be sought from the supplier, the meter operator (MOP) and the distributor to ensure it’s not a one company monopoly pricing structure.  Contract negotiation can be a complex and involved process due to constantly fluctuating wholesale market prices, variable supplier hedging strategies and the requirement for detailed demand data.

Type of Meters

There are four types of Half Hourly Meters that the environment agency describes.

•    Mandatory – for all businesses with high energy usage with a maximum demand of 100 kW or more in any single half-hour period.   Half Hourly Meter is required by law because of the annual amount of energy they consume.
•    Voluntary – not required by law, building owners or occupiers who have opted to have HHM installed for the provision of improved data for energy efficiency and up to the minute accurate billing information.
•    Light – also called Smart Meters or Automated Meter Readers (AMR) are installed voluntarily for the above benefits.
•    Pseudo – also called UnMetered Supplies UMS).  Quite rare in the UK, used generally by councils for street lighting & billboards  etc.

Identifying your Half Hourly Meter


Electricity bills should contain a Supply Number that indicates whether the meter is half hourly or not.   
The S number on your bill will help you with identification.  If the S number has a ‘00’ in the top left box, then you have a half hourly meter.  It could be a ‘Voluntary’ or ‘Light’ Half Hourly Meter if the numbers are 05, 06, 07, or 08.  The electricity supplier or meter operator will be able to confirm the status of the meter if required.

Half Hourly Meter Pricing

Half hourly meter pricing is different to standard electricity pricing. Due to your energy supplier receiving accurate and regular data on your usage, they are able to calculate your pricing on the specific energy usage of your business.

To Save on Half Hourly Energy Costs call us now on 01380 860196