Green Gas Support Scheme and Green Gas Levy

Who is the scheme for?

The Green Gas Support Scheme (GGSS) is designed to support the deployment of new anaerobic digestion (AD) biomethane plants to increase the proportion of green gas in the gas grid.

Regular support payments will be provided to registered biomethane producers based on the volume of eligible biomethane, produced from AD, that they inject into the gas grid.

If you are a producer of biomethane, or plan on producing biomethane in the future, you may be eligible to apply for the GGSS.

All prospective applicants should read our GGSS Guidance for full details on the scheme’s eligibility requirements.

What should I do if I want to apply?

Before applying it is essential that potential applicants familiarise themselves with the requirements of the GGSS Regulations, in particular the GGSS eligibility criteria and ongoing obligations as set out in the scheme regulations. These can be found in the GGSS Guidance.

There are three stages to the application process.

Stage 1: Prospective scheme participants must first apply for a tariff guarantee. This will enable them to secure a fixed tariff rate before their installation is fully commissioned and registered on the scheme.

To apply for stage 1, the plant must be sufficiently developed in order to be able to provide key details such as:

  • evidence of a connection agreement
  • planning permission details
  • expected maximum initial capacity
  • expected volume of eligible biomethane to be injected each year. 

Stage 2: After Stage 1 has been approved, applicants will be required to provide evidence of financial close within three weeks. This should demonstrate that funds are available to cover the complete construction and commissioning of the proposed project, and that these funds are formally committed to the project. See our GGSS Guidance (Stage 1: Initial Application) for more information and a full list of information required. If the Stage 2 application is successful, we will issue a tariff guarantee.

Stage 3: If issued with a tariff guarantee, the applicant can apply for GGSS registration once the plant has been commissioned. The plant must be commissioned by the commissioning date stated when the tariff guarantee was applied for plus a 182 day grace period, or by 30 November 2025, whichever is earlier. After the regulation amendments laid on 14 May 2024 come into effect, this date will be 31 March 2028. Applicants with tariff guarantees issued before 4 June 2024 (when the 2024 regulation amendments come into force) must still commission either before the grace period, or before 30 November 2025 whichever is earlier. Otherwise, the applicant will be unsuccessful in applying for registration.

Having a tariff guarantee does not guarantee that full registration will be granted, and there are circumstances in which we may revoke a tariff guarantee These are given in our GGSS Guidance.

In some cases, we may need to contact applicants for further information to enable us to verify eligibility. When requesting further information, we will apply a deadline, usually five working days. If the information is not provided within the deadline specified, we will reject the application and the budget will be reallocated. Should that applicant wish to re-apply to the scheme, they would need to submit a new stage 1 application and would join the back of the budget allocation queue.

How do I apply?

Applications to the scheme must be made online using the GGSS Portal.  

The first step will be to create a user account.

If the application is being made on behalf of an organisation, the applicant will need to register that organisation after the person making the application has set up their own user account.

We will require a letter of authorisation (LOA) to be completed to confirm who has been given legal authority to act on behalf of the applicant for the purposes of the GGSS.  

Applicants for Stage 3 registration will need to complete a Fuel Measurement and Sampling Questionnaire and submit this as part of their application.

Additional users may be added to the GGSS account in order to be able to provide information in relation to the application but will not be able to submit an application.

What are the tariffs?

For current tariff rates, please see the tariff table page.

Where the tariff start date is on or after 1 July 2022, the initial tariff will be calculated by us using the formula set out in the Regulations. Each year, by 15 March, 15 June, 15 September and 15 December, we will publish the initial tariff rate that will apply where a tariff start date falls within the following quarter.

Application Budget cap

The Application Budget cap is designed to provide a cap against which applications to the scheme will be checked to ensure that there is available budget for them to register and receive payments under the scheme based on their estimated production.

The Department for Energy Security and Net Zero announced that the GGSS Application Budget cap for 2024/2025 would be reduced from £88 million to £51.7 million from April 2024. This was announced on 22 December 2023. The reduction in the Application Budget cap may affect applicants planning to commission in 2024/25.

For applications where a Provisional Tariff Guarantee Notice is issued on or after 1st April of any year, the available budget will be assessed against the revised Application Budget cap applicable from 1 April of that year. This will be the case irrespective of whether the application was submitted before or after 1 April of that year.

If the Application Budget cap is reached and there is insufficient budget available to approve an application, it will be placed into a queue. Applications will then be processed in the order they applied should additional budget become available either through other applications withdrawing or being rejected or through an increase in budget by the Secretary of State each financial year.

Later applications with a smaller capacity may be processed should there be sufficient budget available for that application. Please see The Department for Energy Security and Net Zero GGSS Budget Management document for more details of the budget caps.

Please note that Ofgem must not issue a Provisional Tariff Guarantee Notice where this would cause the budget cap to be exceeded.

The following table shows the budget that has been allocated in each of the financial years.

Number of tariff guarantee applications made 39
Number of provisional tariff guarantee notices given (Exc. any rejected at tariff guarantee stage) 16
Number of tariff guarantees granted 14
Number of registered participants 1
Number of applications for registration in respect of additional biomethane made 0
Number of participants registered in respect of additional biomethane 0
Budget FY 21/22 FY22/23 FY23/24 FY24/25 FY25/26 FY26/27 FY27/28
Budget available* £37,000,000 £37,000,000 £32,900,000 £51,700,000 £80,300,000 £124,900,000 £174,200,000
Budget allocated (based on applications received) £233,938 £2,598,348 £13,832,946 £47,659,238 £64,024,019 £72,188,677 £75,770,991
Budget committed (based on applications granted) £233,938 £2,598,348 £13,832,946 £47,659,238 £59,972,071 £64,678,974 £67,286,709
Remaining budget available £36,766,062 £34,401,652 £19,067,054  £4,040,762 £16,275,981 £52,711,323 £98,429,009

This information represents the queue and granted Tariff Guarantees as of Wednesday 22 May 2024. It is subject to change based on ongoing queue movement and should not be used for the purpose of making commercial decisions; it is for information only.

For further information

Refer to the GGSS Guidance document for more detailed information and guidance before making an application. The comprehensive guidance includes more details relating to:

  • Eligibility criteria
  • How to apply
  • Ongoing obligations