The Green Gas Certification Scheme

The Green Gas Certification Scheme (GGCS) issues, transfers and retires Renewable Gas Guarantees of Origin (RGGOs) within our registry.

RGGOs are issued to green gas producers for units of green gas injected into the gas grid, which displace units of fossil gas. They can then be transferred between a variety of counterparties before being retired and allocated to gas consumers. The GGCS ensures that only one RGGO is issued for each unit injected, that they are transferred securely, and only ever allocated to one consumer. By doing so we provide certainty that green gases are not double counted.

The GGCS is run by Renewable Energy Assurance Ltd who carry out a range of certification and consumer protection activities all of which promote renewable energy and the circular economy. Renewable Energy Assurance Ltd is a company limited by guarantee (number 05720606) and is a wholly-owned subsidiary of The Association for Renewable Energy and Clean Technology, a not-for-profit company limited by guarantee (number 04241430).

Benefits of the Green Gas Certification Scheme

The GGCS is a simple and reliable way for green gas producers to capture the value of their product while guarding against double-counting. It provides an instrument for consumers to show they are using green gas, enabling companies and households to support biomethane production in the UK and, where applicable, lower their reported carbon emissions.

Taking part in the Green Gas Certification Scheme

Producers may open accounts in the GGCS registry where they will be issued RGGOs and can transfer them to trading accounts. Gas Suppliers, Gas Shippers and other interested parties, including consumers, can open trading accounts in the GGCS registry where they can receive RGGOs from producers, send and receive RGGOs from other traders, and allocate them to gas consumers at which point they are retired. Those with an interest in green gas can join as Associate Members without opening an account in the registry.

Renewable Gas Guarantees of Origin (RGGOs)

A RGGO is issued when a kWh of green gas is injected into the grid. Each RGGO contains information about where, when, and how that kWh of green gas was produced. RGGOs allocated to consumers are retired and listed on Retirement Statements which can be verified here.

Latest News:

  • DENA Data Breach

    GGCS is aware of a data breach at DENA ( who operate the German biogasregister ( along with a variety of other schemes and projects. Information about the cyber attack in November 2023 is here forma data security notice has now been published details are given here https://www.dena...

    Posted: 1 March, 2024

  • Guidance from DENA on uses of imported biomethane (updated)

    Follow the link to access guidance from DENA on the use cases for bio-methane imported into Germany - Possible uses of biomethane quantities and certificates – BiogasregisterThis guidance was explored in detail during an recent ERGaR training session - if you are an ERGaR member contact Valentin Calfa, Communication and Policy Officer - - who can provide you with the recording. An update provided in Feb '24 may be of interest to GGCS members. https://www.biogasregister...

    Posted: 20 February, 2024