How the non-Domestic RHI is calculated

Measuring

The Non Domestic Renewable Heat Incentive (RHI) is paid for 20 years on the total measured heat output of the ground source heat pump.

Heat metering and electrical metering will need to be installed to monitor usage to determine RHI payments.

Tariff

For ground source heat pumps the tariff is split in two parts, 8.8p/kWh for the first 1314 hours of operation, (a 15% load factor) and 2.6p/kWh for any operation above 1314 hours. This is to stop people over generating heat simply to claim the tariff.

Calculations

You are paid a certain amount per kilowatt hour (kWhth) and calculations are made according to whether your system is designated ‘standard’ or ‘multiple’, or for systems installed before the 24 September 2013, ‘simple’ or ‘complex’.

For a standard system

Basic definition of a ‘standard’ system:

One appliance, heating one building, with one heat meter, installed after 24th September 2013. Also allows for the ineligible heat loss to be calculated rather than measured using a separate meter when a short distance exists between the heat pump and the property to be heated.

Installations using ‘standard’ metering for RHI payment purposes have two options for calculating the eligible heat output (EHO):

Option 1

Payment = Tariff Level x Heat Generated by RHI Installation (EHO)

(NB where there are NO Ineligible heat uses on the system)

Option 2

Payment = Tariff level x Eligible Heat Used by the RHI Installation (EHO)

(NB where there is NO additional ineligible heat generation plant)

For a multiple system

Basic definition of a ‘multiple’ system:

One ground source heat pump, heating two or more properties, featuring multiple meters, installed after 24th September 2013.

Installations using a ‘multiple’ metering arrangement have to submit:

  • The eligible heat generated;
  • The eligible heat used;
  • The total heat generated on the system or the total heat used on the system.
Option 1

Payment = Tariff Level x Eligible Heat Used on System x Heat Generated by RHI Installation/Total Heat Generated on System

Option 2

Payment = Tariff Level x Eligible Heat Generated by RHI Installation x Eligible Heat Used on System/Total Heat Used on the System

Examples of how to calculate payments for heating systems are available in the RHI Guidance Volume 2, chapter 5, pages 50-51 for ‘standard’ and pages 51-54 of ‘multiple’.

For a simple system

Basic definition of a ‘simple’ system:

One appliance, heating one building, with one heat meter, installed before 24th September 2013.

RHI payments are calculated by multiplying the appropriate tariff by the amount of eligible heat generated in the relevant quarterly period.

The formula is:

Payment = Tariff level x Heat generated by RHI installation

For a complex system

Basic definition of a ‘complex’ system:

One ground source heat pump, heating two or more properties, featuring multiple meters, installed before 24th September 2013.

Once you have entered the meter readings and the three heat data figures required by the IT system on the Non-Domestic RHI Register, the ‘Eligible Heat Output’ (EHO) figure in kWhth will be calculated and displayed.  This is the amount that will be multiplied by your tariff to determine the payment amount.

The formula to determine how many kWh have been produced  is:

Eligible heat used on system x Heat generated by RHI Installation / Total heat generated on system