Do I need metering?

Mae’r dudalen yma ar gael yn Gymraeg.

The Government is introducing changes to the Domestic RHI Regulations. Changes are being introduced in two stages. The first stage of changes to the Domestic Scheme came into effect on 20 September 2017.

The second stage of regulations were laid on 7 February 2018. These new regulations will come into effect subject to parliamentary approval. The parliamentary process usually takes 6 to 8 weeks; not including any recess time.

For more information about changes to the scheme and what they mean to you, please see our changes to the scheme webpage and Factsheet: Important Changes to the Domestic RHI Scheme.

There are two types of metering that you may need on the Domestic Renewable Heat Incentive (RHI) scheme: metering for performance and metering for payment. It depends on your circumstances whether you need to install one or both types of meters to meet the requirements of the scheme.

There is an optional Metering and Monitoring Service Package (MMSP) that you can register for in the Domestic Renewable Heat Incentive (RHI). Those who apply for it get paid extra towards some its costs. It’s a useful way of checking how well your system is performing, as well as helping to hold installers to account. Additionally, installing an MMSP is one way of meeting your metering for performance and/or metering for payment requirements for heat pumps (if these apply to you). 

Solar thermal systems never have to be metered, so if you just have solar thermal you don’t need to read this page.

Metering for Payment

This only applies to Domestic RHI applicants with biomass, air source heat pump and ground source heat pump systems.

If your heating system is accredited to the scheme and requires metering for payment, to receive payments you’ll need to submit meter readings every three months. You also need to meet your other ongoing obligations during the seven years your heating system is accredited under the scheme. Your payments will not be “deemed”, but instead will be calculated based on your meter readings.

Applicants who are metered for payment are paid on the renewable heat that they produce, but from 20 September 2017, the maximum annual payments is capped at the deemed annual heat demand of your property based on the figure in your EPC - or the relevant heat demand limit - whichever is lower. Below we’ve set out the three most common situations where you’ll need to have meters for payment.

Where your plant needs to be metered for payment.

The most common situations in which you will need to be metered for payment are: 

  1. If you have ‘back-up heating’.
  2. Where you have a biomass heating system that isn’t designed to heat the whole property.
  3. Where your property is occupied for less than half the year.

This list is not exhaustive. For further details and examples, please read our Essential Guide to Metering.

To learn more about metering for payment, see our key term.

Metering for Performance

This section only applies to new Domestic RHI applicants with heat pumps after the new regulations come into effect.

The second stage of regulations were laid on 6 February 2018.  If you apply and are successfully accredited to the Domestic RHI on or after the day they come into force, all new applications for air source heat pumps and ground source heat pumps will need to have electricity metering arrangements alongside their heating systems to be eligible for the scheme.

This change is being introduced to enable consumers to monitor the performance of their heating system and to provide a better understanding of the heat pump system’s electricity usage. Efficient heat pumps are essential to deliver savings on energy bills for consumers.

If your heat pump is metered for payment, you’re already required to have electricity meters and heat meters, so you already fulfil your requirements for metering for performance. You won’t need to install further electricity metering for performance.

If you’re only required to have meters for performance, your Domestic RHI payments will continue to be based on the deemed annual heat demand of your property based on the figure in your  Energy Performance Certificate (EPC)  – or the relevant heat demand limit - whichever is lower. Payments for heat pumps will continue to be made only on the renewable portion of the heat demand.

If you require metering for performance, you have three electricity metering options:

  1. standalone electricity metering
  2. on-board electricity metering
  3. Metering and Monitoring Service Package (MMSP)

The meter(s) will be required to record and display:

  • electricity used by the plant to generate heat;
  • electrical input into any supplementary electric heater controlled by the same control system as the heat pump; and
  • electrical input into any immersion heater for a domestic hot water cylinder where the immersion heater is controlled by the same control system as the heat pump.

This will need to be added on your MCS Certificate. For full details and examples, please read our Essential Guide to Metering.

Note: If there are multiple supplementary or immersion heaters controlled by the same control system as the heat pump, a single meter can be installed to record the total combined electrical input; or, each heater can be metered separately. Metering input to each heater separately could help identifying if there is an issue with an individual immersion heater/supplementary heater.To learn more about metering for performance, see our key term.

Publications and updates

  • Published: 29th Nov 2017
  • Guidance
  • 1 Associated documents
Participants on the Domestic RHI who need metering for payment will need to submit meter readings quarterly.

  • Published: 24th Mar 2016
  • Guidance
  • 1 Associated documents
This guide starts with the circumstances which make metering compulsory for some people applying for the Domestic RHI, all the way through to submitting meter readings for payments.