Green Gas

What Green Gas does

The Green Gas Certification Scheme (GGCS) operates the UK's primary registry for Renewable Gas Guarantees of Origin (RGGOs), issuing a certificate for each kWh of biomethane (and, since 2025, hydrogen) injected into the gas grid and tracking the certificate through trade and final retirement to prevent double-counting of environmental attributes. Established in 2011 by founder members including British Gas, E.ON, National Grid, Thames Water, and Milton Keynes Council, GGCS is run by Renewable Energy Assurance Ltd, a not-for-profit company limited by guarantee and wholly owned by the Renewable Energy Association. The scheme is governed by its participants, and its standing is reinforced by designation as an Approved Certification Scheme under the UK Green Gas Levy.

The core product is the GGCS Registry, where biomethane producers open accounts to receive RGGOs, gas suppliers and traders transfer them, and end consumers retire them against reported gas use. The registry database migrated to Grexel's G-REX platform in August 2024 and Scheme Rules were updated to Version 4. GGCS generates revenue through scheme membership fees and per-unit gas throughput fees on a not-for-profit basis; throughput fees were reduced by 75% in a recent year, saving participants approximately £120,000 in aggregate. Customers span biomethane producers (~130 plants), gas suppliers/shippers (~108 trader accounts and 42+ supplier members), corporate consumers (including John Lewis Partnership, Kingspan, Landsec, Sainsbury's, Sopra Steria, Unilever), transport operators (e.g., Nottingham City Transport, CNG Fuels), and over one million UK households on green gas tariffs via energy suppliers such as E.ON and British Gas.

In 2025 GGCS retired 4.2 TWh of RGGOs (up from 3.4 TWh in 2024) and issued the UK's first Guarantees of Origin for hydrogen. It is a founding member of the European Renewable Gas Registry (ERGaR) Certificate of Origin Scheme, enabling cross-border RGGO transfers across participating European registries, and contributes to GHG Protocol corporate-standards revisions and to DESNZ discussions on harmonising RGGO treatment in the UK ETS with the EU ETS.

Name

Green Gas

Legal name

Renewable Energy Assurance Ltd

Website

https://greengas.org.uk

Company type

Private

Founded year

2011

Operating status

Operating

Headcount range

11–50 employees

Short description

Green Gas Certification Scheme (GGCS) operates the UK's primary registry issuing Renewable Gas Guarantees of Origin (RGGOs) for biomethane and hydrogen injected into the gas grid, serving producers, gas suppliers, corporate consumers, and over one million UK households.

Ownership category

akta.pro rank

Headquarters

HQ city

London

HQ country

United Kingdom

HQ region

Europe

Offices1 record

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Technology or R&D, Operations, Marketing or Sales, Others

Revenue model

1. Scheme Membership Fees: Fees charged to participants for operating accounts in the registry. The scheme is not-for-profit and last year participants decided to reduce gas throughput fees by 75%, saving participants a total of £120,000.
2. Gas Throughput Fees: Transaction-based fees charged on gas volume processed through the registry. The scheme reduced these fees by 75% in a previous year.

Go-to-market motion1 record

Distribution channels3 records

Marketing channels6 records

Core offering

The Green Gas Certification Scheme operates a registry platform that issues, transfers and retires Renewable Gas Guarantees of Origin (RGGOs) for each kWh of biomethane injected into the UK gas grid. Producers, gas suppliers, gas shippers and traders open registry accounts to receive, trade and allocate RGGOs to end consumers, with the scheme ensuring one RGGO is issued per unit injected and only ever allocated to one consumer. End-consumer retirements are evidenced via Green Gas Certificates (Retirement/Cancellation Statements) used for corporate Scope 1 emissions reporting and household green gas tariffs.

Product overview

The Green Gas Certification Scheme (GGCS) operates as a certification and registry platform that issues, transfers, and retires Renewable Gas Guarantees of Origin (RGGOs). The core product is the GGCS Registry where green gas producers receive RGGOs for biomethane injected into the gas grid. These RGGOs can be traded between counterparties (Gas Suppliers, Gas Shippers, traders) and ultimately retired as Green Gas Certificates for end consumers. The scheme provides certainty against double-counting and supports emissions reporting. GGCS also publishes guidance documents and facilitates market information through third-party providers.

Differentiator

Problem solved

Functional benefit

Products and services

• Renewable Gas Guarantees of Origin (RGGOs) Certificate issued by GGCS for each kWh of green gas injected into the gas grid, recording where, when and how the gas was produced. RGGOs can be transferred between counterparties (producers, gas suppliers, gas shippers, traders) and ultimately allocated and retired against end-consumer gas use.
• GGCS Registry Registry platform (now powered by Grexel's G-REX database) where green gas producers open accounts to receive RGGOs for injected biomethane, send and receive RGGOs, and allocate them to consumers; gas suppliers, gas shippers and other parties can open trader accounts to trade and allocate RGGOs.
• Green Gas Certificates (Retirement/Cancellation Statements) Retired/cancelled RGGO statements issued to consumers listing the RGGOs allocated to their gas use, providing verifiable evidence of biomethane consumption for corporate Scope 1 emissions reporting and household green gas tariff claims.
• Guarantees of Origin for Hydrogen Extension of the GGCS RGGO framework to cover green hydrogen injected into the UK gas transmission system, enabling issuance, transfer and retirement of Guarantees of Origin for blended hydrogen volumes.

Quantifiable outcome

• 4.2 TWh of RGGOs retired/cancelled in 2025
• +6 more outcomes

Named customers16 records

Segments6 records

Ideal customer profiles4 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature3 records

Partnerships

14 partnerships are on record, tiered core and minor.

• Grexel (G-REX)coreTechnology or Integration · 9 August 2024GGCS migrated its registration database to Grexel's G-REX platform in August 2024. Grexel provides the IT platform where RGGOs are held and managed.
• British GascoreStrategic or Co-development PartnerFounder Partner of the GGCS scheme. One of the major energy suppliers involved in establishing the certification scheme in 2011.
• E.ONcoreStrategic or Co-development PartnerFounder Partner of the GGCS scheme. Major energy company that has continued to offer green gas tariffs including EV renewables tariff.
• Thames WatercoreStrategic or Co-development PartnerFounder Partner of the GGCS scheme. Water utility company involved in establishing the certification scheme.
• Milton Keynes CouncilcoreStrategic or Co-development PartnerFounder Partner of the GGCS scheme. Local government authority supporting green gas development.
• National GridcoreStrategic or Co-development PartnerFounder Partner of the GGCS scheme. Gas network operator that worked on first high pressure grid connected CNG filling station and first UK Guarantees of Origin for hydrogen.
• CNG Services LtdcoreStrategic or Co-development PartnerFounder Partner of the GGCS scheme. UK's leading provider of biomethane-to-grid connections, having worked on 90% of UK's 50 biomethane connections.
• InterconnectorcoreStrategic or Co-development PartnerFounder Partner of the GGCS scheme. Company involved in gas interconnectors supporting cross-border gas flows.
• European Renewable Gas Registry (ERGaR)coreStrategic or Co-development PartnerGGCS is a member of ERGaR Certificate of Origin (CoO) Scheme. The scheme allows participating registries to transfer RGGOs and equivalent certificates between their registries across Europe.
• ArgusminorOthersMarket information provider offering price assessments and analysis for renewable gas and electricity markets. GGCS provides market information links to Argus pricing data.
• Cornwall InsightminorOthersEnergy consultancy providing green certificate market survey for RGGO pricing levels, demand/supply trends, and market sentiment.
• S&P Global Commodity InsightsminorOthersCommodity price and analytics provider publishing European and UK Biomethane Guarantee of Origin Price Assessments and methane-related certificates.
• Quantum Commodity IntelligenceminorOthersMarket intelligence provider offering daily and weekly RGGO price assessments and regulatory/policy news for renewable gas markets.
• VeytminorOthersMarket intelligence company (formerly Greenfact) providing RGGO and Biomethane Certificate spot prices, latest trades, and analytical reports.

Scale indicators21 records

Recent moves6 records

Expansion highlights5 records

Emerging players

• EnergyTag: Industry initiative defining standards for renewable gas (biomethane and hydrogen) traceability and certification. Comparable to GGCS at the certification-standards layer and a potential interoperability partner/competitor in the UK and EU markets.
• CertifHy: European hydrogen Guarantees of Origin scheme run under the CertifHy protocol — directly comparable to GGCS's newly launched hydrogen GoO functionality. Operates in an adjacent vertical (hydrogen vs biomethane) with overlapping issuance/registry mechanics.

Others

• OFGEM (Office of Gas and Electricity Markets): UK regulator of gas and electricity markets. Not a registry competitor but a key counterpart in the Green Gas Levy / Approved Certification Scheme regime that legitimizes GGCS-issued RGGOs within UK compliance frameworks.
• Grexel (G-REX): Provider of the G-REX certificate registry platform used by GGCS and other European certificate schemes. Technology partner and infrastructure layer for issuance, transfer, and retirement of energy Guarantees of Origin; competes with other registry platforms and underpins GGCS's operations.
• Gold Standard: Voluntary carbon credit certification body with a registry used by corporates for emissions claims. Adjacent/competing infrastructure for the corporate-emissions-reporting budget that also drives demand for RGGOs from GGCS.
• Verra (VCS Registry): Global standards body for voluntary carbon markets, operating a major carbon credit registry. Adjacent to GGCS rather than direct competitor, but competes for corporate-emissions-claims budget and partially overlaps with biomethane attribute claims via voluntary carbon credit pathways.

Regional players

• Energinet (Denmark): Danish TSO that operates biomethane GoO issuance and registry functions for the Danish gas market. Comparable scheme structure to GGCS but serves the Danish biomethane market; cross-border RGGO transfers through ERGaR make it a functional peer.

Direct peers

• Association of Issuing Bodies (AIB): European association of energy certificate issuing bodies that defines standards for Guarantees of Origin across electricity, gas, and hydrogen. AIB's EECS framework underpins RGGO-style instruments in Europe, making it a structural peer in the certificate-system standards space.
• European Renewable Gas Registry (ERGaR): Umbrella European body coordinating biomethane Guarantee of Origin registries across member countries. GGCS is itself a founding member; other member registries (e.g., Vertogaz in France, Energinet in Denmark) operate RGGOs with interoperable attributes comparable to GGCS's scheme.
• Vertogaz (France): France's biomethane Guarantee of Origin registry operated by GRDF and GRTgaz. Analogous to GGCS — issues, transfers, and retires biomethane certificates for gas injected into the French grid — and cross-border interoperable with GGCS via ERGaR.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks5 records

Key highlights7 records

Customer concentration

• Xx.com/GreenGasCert
• LinkedInlinkedin.com/company/green-gas

Revenue estimate

Valuation estimate

Number of profiles

Profiles2 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Green Gas