German Emissions Trading Authority

Registry architecture

In the following, the structure of the Union Registry will be explained. The Union Registry is a record of who is in possession of which emission allowances. In addition, all transactions are executed and documented here. First there is an introduction to the international registry architecture and European emissions trading. Another topic is the Union Registry’s EU Section. This is followed by the Kyoto Section and the Public Section of the Union Registry.

International registry architecture and the European Emissions Trading Scheme

The European Union Registry as the technical basis for the European emissions trading is part of an international registry architecture. It is connected with other Kyoto registries via the International Transaction Log (ITL). ITL is operated by the UNFCCC based on the "Data Exchange Standards for Registry Systems under the Kyoto Protocol (DES)". Any transaction of Kyoto certificates is checked by ITL for its compliance with DES. If no discrepancies are found, ITL confirms the transaction, otherwise it will be rejected. Compliance with the rules of the European Emissions Trading System (EU ETS) is checked by the European Transaction Log (EUTL). EUTL is responsible for EU-ETS-related transactions and processes such as opening and closure of accounts. Sometimes an additional check is carried out by EUTL after the ITL has forwarded the issue such as transactions with Kyoto certificates. There are issues checked only by EUTL such as European allowance transactions. This international registry architecture includes the CDM registry which is also run by UNFCCC. It is used to issue certificates from Clean Development Mechanism (CDM) projects. The certificates are called Certified Emission Reductions (CERs). Apart from a few exceptions, transactions with CERs from the CDM registry can only be made to accounts in other national Kyoto registers. Transactions from other national Kyoto registries of the participating parties in the Kyoto protocol to accounts in the CDM registry are not usually possible.

The figure below shows how the Union Registry is integrated into UNFCCC’s existing registry architecture.

Registry Architecture of the UNFCCC


The EU section of the Union Registry

All processes and transactions of the EU Emissions Trading Scheme (EU ETS) are performed in the EU section of the Union Registry. Here are found the operator holding accounts, aircraft operator holding accounts, trading accounts, person holding accounts and verifier accounts of the EU ETS. Except for the verifier accounts, the account identifier of the different account types always begins with EU-100. The account identifier of the verifier accounts starts with EU-0. These accounts cannot hold certificates: they are only used to register or approve verified emissions for operators and aircraft operators in the registry.

European emission allowances (allowances for short) can only be held in accounts in the EU ETS section (EU-100 accounts). When allowance transactions take place, EUTL checks the compliance of the transaction with the rules of EU ETS. ITL is not involved in allowance transactions.

The accounts in the Union Registry are managed by the Member States. This means that the respective Member States consider account applications, check documents required for opening an account and are the contacts for users who have asked questions. For Germany, the German Emissions Trading Authority (DEHSt) at the German Environment Agency is responsible.


The Kyoto section of the Union Registry

The Kyoto section of the Union Registry holds the national Kyoto Registry for the relevant EU Member State. In this section, the nation state stores its national accounts and evidence accounts under the Kyoto Protocol. In the national Kyoto Registry there are the (former) operator holding accounts and person holding accounts with their existing country-specific account identifiers as they existed prior to the switch-over to the Union Registry. The former operator holding accounts in the national Kyoto Registry (DE-120) will be closed in the foreseeable future while person holding accounts will remain and can also be opened. Thus, there are person holding accounts in the EU section of the Union Registry whose identifiers start with EU-100 and also in the Kyoto section which contains specific country identifiers and also the identifiers of the account type such as DE-121.

Kyoto certificates such as CERs or ERUs may be held both on the Kyoto section accounts and on the EU section accounts. Transactions of Kyoto certificates are checked both by ITL and EUTL for compliance with the applicable regulations.

The following shows the architecture of the Union Registry.

Architecture of the Union Registry


Public section

The Union Registry also provides publicly available information on various topics such as allocations of emission allowances, compliance status of operators and aircraft operators as well as certain account information such as the account holder. These data can be found on the European Commission’s website for the EU ETS.


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