Half-hourly meters

How is half-hourly data collected?

All AMR half-hourly data is retrieved remotely by an appointed Data Collector (using landlines or mobile SIM cards attached to the meter) and sent to us and the Distribution Network Operator each day.

All smart half-hourly data is transmitted from the meter via the Smart DCC (Data Communications Company) secure encrypted network and delivered to us and the Distribution Network Operator each day.

New roles – Data Services and Market-wide Data Service – will replace Data Collector and Data Aggregator as part of the Market-wide Half-Hourly Settlement (MHHS) Programme.

Under MHHS, if you don’t have a smart or AMR meter or half-hourly data isn’t available, you'll still be settled half-hourly, using estimates.

You can access this HH data via our SSE Clarity platform.

What other data is recorded by the meters?

All smart and AMR meters record your actual consumption, but are also programmed to record something we call Reactive Data – this is measured in kVArh lag/lead data.

This is a measurement of the efficiency of the site – generally you can see this most effectively in factories or other places with large machinery. This means in order to get the required power to the machinery, the meter will draw additional power to correct for any inefficiencies with the equipment. This Reactive Data is recorded and sent to the distribution network operator who will then bill us. This is known as the Reactive Power Charge. Where possible, you could install power factor correction equipment to help reduce these costs.

What are Distribution Network Operator (DNO) pass-through charges?

Pass-through charges are set by the local Distribution Network Operator (DNO). They include Available Supply Capacity, Excess Capacity and Reactive Power charges.

What is Available Supply Capacity?

If you have HH electricity meters, Available Supply Capacity (also referred to as Av Cap or Maximum Import Capacity) can make up a significant proportion of your electricity costs.

Measured in kVA, the Available Supply Capacity is used to increase the Maximum Demand and is essentially the amount of electricity the local DNO is required to make available to your site at any one time. This is paid indirectly to the DNO via your energy bill, and you will be charged whether or not you require it. Amendments can only be agreed directly with the DNO, where possible.

What happens if we use more than the available capacity?

You may be charged for exceeding your Available Supply Capacity if you've expanded a site’s function without asking for the Available Supply Capacity to be increased. These penalties are referred to as ‘Excess Capacity’ charges and can rack up significantly over time.

The DNO will inform us every month of the available capacity agreed, and any excess charge to apply.

What are Triads?

Triads are the three half-hour periods of peak power demand across the national grid in a year (from November to February). These three readings are averaged then used to calibrate the system costs, which are passed onto the industry.

In many areas, Triad charges are zero; most sites pay a fixed daily charge based on consumption and connection type. AMR meters with current transformers (CT) will have an element of charges calculated by Triads post-MHHS.

What is a Transmission Network Use of Systems (TNUoS)/Triad Interim Payment?

Although TNUoS/Triad Reconciliation is based on peak demand periods from the winter months, November to February, a Triad year runs from April to March.

As a result, for energy-only contracts, the customer’s monthly invoices from April to February will recover a Triad Interim payment. This is a monthly contribution (advanced payment) towards the reconciliation that will take place with the March invoice.

Can I upgrade to a half-hourly AMR or smart meter?

We can help you upgrade a meter. We recommend that you first check your site requirements. If you have a traditional gas meter or a whole current electricity connection and the power required won’t exceed 69KVA, you can upgrade to a smart meter by registering your interest here.

If you have a current transformer or need one because the power required will exceed 69kVA, we can install a HH AMR meter. If you don’t yet have a current transformer, you'll need to have any relevant supply upgrade agreed and completed with the Distribution Network Operator (DNO) before we can upgrade the meter. We recommend following these steps:

1. If the relevant distribution work has already been completed please complete the Replacement Meter Appointment Form
2. Download an Upgrade to Supply Form from our website and ensure distribution works have been completed
3. Arrange a Half-Hourly Meter Operator agreement with your chosen agent – you can find a list of these on meteroperators.org.uk
4. Arrange a half-hourly supply contract with our sales team
5. Return the documents to our sales team, re-affirming the requirement for a meter upgrade for them to process the request.

What is the role of a Meter Operator (MOP)?

A Meter Operator (MOP) is an agent responsible for installing and maintaining electricity meters at a site.

An MOP contract, where customers are billed directly by the meter operator, can be independently agreed separately to any electricity supply agreement.

Please let us know if you have an independent agreement with any metering service providers. If you haven't chosen any agents, we’ll appoint them on your behalf.

You can find a list on meteroperators.org.uk.

What is the role of a Meter Asset Manager (MAM)?

A Meter Asset Manager (MAM) is an agent responsible for installing and maintaining gas meters at a site; often these can be the same agent, but this isn’t essential.

A MAM contract, where customers are billed directly, can be independently agreed separately to any gas supply agreement.

Please let us know if you have an independent agreement with any metering service providers. If you haven't chosen any agents, we’ll appoint them on your behalf.

What is the role of a half-hourly data collector (DC) and data aggregator (DA)?

The Data Collector (DC) is an accredited organisation that collects and validates metering data, then sends it to the Data Aggregator (DA). The DC is chosen by the supplier or the customer but must be approved by the supplier. The DA combines data from multiple DCs for billing purposes. Often, the DC and DA are the same company, but this isn’t essential.

The roles of MOPs, DCs and DAs are evolving. MOPs will transition to Metering Services, DCs to Data Services, and DAs to the Market-wide Data Service.