Thursday 25th of November 2021 | Posted In: Renewable energy, Generating energy

Green Gas Support Scheme (GGSS) – RHI Biomethane but in a different guise

25TH November 2021 UPDATE - The GGSS is expected to open for applications on 30th November 2021 and remain open until 30th November 2025. BEIS have set a target of achieving 20 TWh/year from biomethane by 2030. Taking into account operational biomethane plants already receiving RHI support, over the 4 year window for applications there is scope for hundreds of new biomethane plants (of varying sizes) to be accredited on the scheme.

Draft legislation for the GGSS has just been published; this has yet to be made a UK Statutory Instrument but is the best information we have to-date. Ofgem have also published their consultation response which is more reader-friendly. Tariff guarantees (TG) will be a compulsory stage of the application process; budget caps will be published ahead of the scheme launch and budget allocation updates will be published quarterly.

Ofgem are keen to avoid high-value assets from being ‘stranded’ as the RHI scheme closes (31st March 2022) and the GGSS opens (30th November 2021):

  • If you have an RHI Tariff Guarantee and you think that you will miss the RHI commissioning deadline of 31st March 2022, it will be possible to make an application under the GGSS prior to the closure of the RHI scheme. BUT…. in order to do so, you must withdraw your RHI application first, and Ofgem must receive this notification by 29th November 2021.
  • In the event that the Tariff Guarantee is not withdrawn and the RHI’s commissioning deadline is missed, the Tariff Guarantee will expire on the 31st March 2022; from this date onwards, the project will be able to make an application under the GGSS if all the pre-requisites are met.

Should you wish to make an application under the GGSS you cannot make an application if the equipment has been used to produce biogas or biomethane prior to the new regulations coming into force (30th November 2021). The GGSS Regulations state that the equipment integral to the production of biomethane must never have been used for RHI registration at any time; individual components may not be salvaged and re-used for the purposes of a new registration on the GGSS. Ofgem do not consider “feedstock treatment and pre-processing equipment, and digestate treatment equipment” to come under this definition.

All sites will be subject to an Ofgem audit in the first year of operation; a service which we  can assist with so please get in touch in plenty of time so we can help ensure your compliance.


26th March 2021

At a glance, the new Green Gas Support Scheme looks and feels very reminiscent of the RHI Biomethane scheme.

There are a few extra requirements to submit a properly made application, but nothing too surprising or onerous. The scheme will close to applicants in Autumn 2025 but the tariff will last for 15 years.

Notable features:

  • 50% of all biomethane (by energy content) must be from waste/residues to qualify for maximum subsidy support – this threshold is minded to increase over time
  • Greenhouse Gas (GHG) emission threshold to receive payment is 24g of CO2 equivalent per MJ of biomethane injected compared to the current RHI threshold of 34.8g of CO2 equivalent per MJ biomethane injected
  • Injection hubs are NOT eligible
  • Only biomethane injection from new AD plants are eligible for the scheme. Expansions and conversions from CHP will NOT be eligible at this time

As a biomethane plant will take at least 1-2 years to fully commission, now is the time to start considering the critical elements while we await confirmation of the finer details.

If you’re considering applying you can discuss your individual situation with the NFU Energy team on 024 7669 8885.