Changes to the Non-Domestic RHI regulations (May 2018)


Publication date

Scheme name

Non-Domestic RHI

Summary of RHI reforms

The latest RHI reforms for Domestic and Non-Domestic have successfully passed through Parliament and came into effect on 22 May 2018. This results in changes to both Non-Domestic and Domestic RHI schemes in Great Britain.

Domestic RHI changes

Systems changes will be deployed for the 22 May 2018, with no system downtime expected and guidance will be released. Ofgem will publish a more detailed note in June, outlining the upcoming major changes to the Domestic scheme, with regards to Assignment of Rights regulations which are due to come into effect on 27 June 2018. Given the other current Regulation changes have a greater impact on the Non-Domestic RHI scheme customers, the remainder of this update focuses on changes to the Non-Domestic RHI scheme.

Non-Domestic RHI changes

Applications for Tariff Guarantees on the Non-Domestic RHI will be available from 10am on the 22 May 2018.

Ofgem would like to reassure the renewable heat industry that we are ready to fully administer the new RHI regulations from the 22 May 2018. We will release IT solutions for Tariff Guarantees and publish guidance on our operational approach to all aspects of these regulations coming into effect on 22 May. We will introduce further system updates to support the other Non-Domestic RHI changes over the coming months. Further details on these key changes are in the rest of this document.

Tariff Guarantees

Our Guide to Tariff Guarantees has recently been revised (with the update published on 16 May 2018) following industry feedback, and should be consulted before submitting a Tariff Guarantee application.

Ofgem is aware of the expected high volume of Tariff Guarantee applications from the outset. IT development to support this has been prioritised, and was deployed for 10am on 22 May 2018. Applicants should note that a User Account on the RHI Register will be required to submit a Tariff Guarantee application. The Tariff Guarantee application can be found under the application section of the RHI Register; by creating a new application and selecting the Tariff Guarantee option. 

Shared Ground Loops (SGL)

If you want to know more about SGLs and in particular how you tell whether any of your heat pumps are eligible for deemed payments please see our Easy Guide to shared ground loops that we published in February 2018. A revised version of this guide (with minor clarifications) was published on 22 May 2018.

An updated application form tailored for SGLs will not be in place for 22 May 2018. Instead we expect this IT solution to be deployed in the following months. We will keep industry informed on progress. In the interim we will be accepting SGL applications from the 22 May 2018 as follows:

  • If you are applying for a SGL system (essentially a Ground Source Heat Pump (GSHP) or Water Source Heat Pump (WSHP) with more than one heat pump) and have no heat pumps which will be eligible for deeming, you can use the existing heat pump application form as normal.
  • If you are applying for a SGL system and have 1 or more heat pumps that will be eligible to receive deemed payments you will need to follow the following process:
  1. Start a GSHP or WSHP application as per normal through the RHI register
  2. Enter the correct number of electricity meters on your system in HF130-2
  3. For question HI100-1 about metering please enter the figure ‘1’
  4. For question HH130-1 in your application, please complete and upload the Shared Ground Loops questionnaire (which is an editable PDF) and is at the bottom of this webpage 
  5. When filling in the meter grid you will need to submit 1 heat meter (because of the ‘1’ entered for question H100-1). Please fill in as follows:



Serial Number


Opening Meter reading

Opening meter reading date




SGL application


[Date of application]

You can then fill out the rest of the meter grid as normal with details of your electricity meters (the number of which you will have noted in your answer to question HF130-2).

  1. Complete any remaining questions in the application form and submit
  2. Once submitted Ofgem will review and upload all necessary information into the new application form that we have designed for SGL’s once it becomes available. Please note that this process is in line with the regulations and we will endeavour to meet our existing service level agreements with regards to application review.

Eligible Heat Use changes

The amending regulations set out changes to the eligible uses of heat supported for applications made on or after 22 May 2018. This includes the removal of wood fuel drying, digestate drying, waste drying or processing, and domestic swimming pools on Non-Domestic premises as eligible uses of heat.

Revised questions in the application form for heat uses on the RHI register will not be in place on 22 May 2018. In the first instance we will be asking supplementary questions via an editable PDF document, and we will include some of these changes in the Register, where appropriate, over the coming months. All applicants to the RHI (for all technologies) should continue to submit applications as normal and provide a filled-in copy of the Eligible Heat Use questionnaire which is at the bottom of this webpage. Ofgem’s preference is that this completed questionnaire is uploaded to the RHI Register during the application process. If applicants face difficulties in uploading, it can be sent by e-mail to with a reference to the relevant RHI number in the subject line.

Feedstock requirement

The IT solution for submitting data about the feedstock requirement will not be deployed on the 22 May 2018. This will follow in a later IT update. There is a 3 month window in which to submit feedstock requirement information so we do not anticipate any impact on participants. 

Preliminary applications 

Preliminary applications are now available for Ground Source Heat Pumps with a capacity of 100kWth or greater and Air Source Heat Pumps with a capacity of 45kWth or greater. If you are interested in applying for preliminary accreditation on or after the 22 May 2018, please e-mail with the e-mail title ‘GSHP/ASHP preliminary application – [NAME]). We will then respond to you with details on the process to follow.


Ofgem would like to thank everyone in advance for their patience and support as we administer these changes to the regulations. We welcome any feedback through the usual channels on any impacts our administration is having  and on the process changes we will be introducing over the coming months.

Ofgem published a full set of guidance in support of these regulation changes on the 22 May for both the Domestic and Non-Domestic RHI on the Ofgem website.