Two European organizations, two systems—and how they’re connected
ERGaR – European Renewable Gas Registry
What is ERGaR?
ERGaR is an international, nonprofit organization based in Brussels. It was founded to establish a trusted system for the cross-border transfer of biomethane certificates between national registries in Europe. To this end, ERGaR brings together established gas registries and key players in the European renewable gas market.
What exactly does ERGaR do?
- Operating the Cert-X Europe trading platform for the cross-border exchange of Certificates of Origin (CoO) between national registries
- Harmonizing the organizational, technical, and audit-related requirements of existing national biomethane registries
- Ensuring mass balance for renewable gases distributed via the European gas network
- Supporting the establishment of national registries in European countries and their integration into the ERGaR system
- Protection against double counting: Each certificate is uniquely recorded and can be used only once
ERGaR’s core objective is to interconnect national registries so that biomethane certificates can be traded securely and transparently across national borders. For Germany, the dena Biogas Registry is integrated into ERGaR as the national partner registry.
AIB – Association of Issuing Bodies
What is the AIB?
The Association of Issuing Bodies (AIB) is an international nonprofit organization that serves as the umbrella organization for government-designated issuing bodies responsible for Guarantees of Origin (GOs) in Europe. Its members are typically transmission system operators, regulatory authorities, or energy market operators that are responsible for administering GOs in their respective countries.
What exactly does the AIB do?
- Development and operation of the European Energy Certificate System (EECS)—the European standard for guarantees of origin
- Operation of a central hub for the cross-border transfer of GOs between national registries, eliminating the need for bilateral connections
- Standardization of the issuance, transfer, and cancellation of guarantees of origin for all energy sources: electricity, gas, and hydrogen
- Ensuring transparency for end consumers: GOs form the basis for electricity disclosure in Europe
The AIB ensures that guarantees of origin function according to uniform rules throughout Europe. Its EECS system has been established for electricity for nearly two decades; since 2019, there has also been an EECS Gas Scheme for gaseous energy sources such as biomethane and hydrogen. The legal basis is provided by Article 19 of the Renewable Energy Directive (RED II/RED III).
Enquire now
A Comparison of ERGaR and AIB
The following table shows the key similarities and differences:
|
|
ERGaR |
AIB |
|
Focus |
Renewable gases (primarily biomethane) |
All energy sources (electricity, gas, H₂) |
|
Instrument |
Certificates of Origin (CoO) |
Guarantees of Origin (GO) via EECS |
|
Platform |
Cert-X Europe |
EECS Hub |
|
Members |
National Gas Registers and Market Participants |
Government-Designated Issuing Bodies |
|
Legal Basis |
Private Sector / Voluntary |
Art. 19 RED II/RED III (EU law) |
|
Focus |
Mass balance + certificate transfer for biomethane |
Standardization + disclosure for all energy sources |
|
German Register |
dena Biogas Registry |
UBA (Certificate of Origin Registry) |
How are ERGaR and AIB related?
ERGaR and AIB pursue similar goals—the cross-border, trustworthy transfer of certificates—but from different perspectives. ERGaR focuses on the gas market and the interconnection of national biomethane registries via the CoO system. The AIB, on the other hand, standardizes certificates of origin across energy sources and provides a legally established framework through the EECS.
In practice, the systems can complement each other: A biomethane producer can trade its certificates across borders via ERGaR and, at the same time, provide a legally recognized guarantee of origin for the end consumer through AIB’s EECS system. The further integration of both systems is an active topic in European energy policy.
Sources
- ERGaR – European Renewable Gas Registry (ergar.org)
- AIB – Association of Issuing Bodies (aib-net.org)
- EECS Gas Scheme – AIB
- Renewable Energy Directive 2018/2001 (RED II), Article 19
- dena Biogas Registry – International Trade / ERGaR
As of February 2026
