Guarantees of origin for renewable energy sources

The market share of green electricity has increased dramatically in recent years in Germany. Electricity consumers need to be confident that the green electricity they pay for does in fact come from renewable sources. Guarantees of origin (GO) prove the origin of renewable energy in a transparent way and provide electricity consumers the necessary reliability.

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Register of guarantees of origin (HKNR)

The mandatory electricity disclosure that electricity supplier are required to carry out (in accordance with section 42 to the German Energy Industry Act (EnWG)) provides customers with important information concerning their electricity consumption. Since January 2013 electricity supplier may only disclose  renewable electricity on electricity bills and advertisement if they have cancelled GOs for the delivered amount of energy proving the renewable origin in the Herkunftsnachweisregister (Register of guarantees of origin). This measure makes disclosure more reliable and prevents electricity suppliers from double selling renewable energy.

The picture shows as a flow chart how and by whom guarantees of origin are issued and cancelled in Germany.
Flow chart of guarantees of origin in Germany
Source: Michael Marty, Magdalena Weimeister / UBA

Information for electricity suppliers

The detailed rules and regulations governing the HKNR can be found in the Guarantees of Origin Implementing Ordinance (Herkunftsnachweis-Durchführungsverordnung – HkNDV). Participants, e.g. electricity suppliers are charged a fee for using HKNR. Please find information concerning the fees in the Guarantees of Origin Fees Ordinance (Herkunftsnachweis-Gebührenverordnung – HkNGebV).

When registering for HKNR, bear in mind that in most cases a post office PostIdent procedure needs to be carried out for identification. Therefore it will take a few days until your registration will be approved and your account will be opened. If you have your permanent domicile outside Germany you may choose either to be identified in a German post office via the PostIdent procedure or to upload an electronic copy of your passport in the HKNR. To register as a natural or legal person, go to the HKNR home page.
The registration procedure works as follows (be sure that you have the documents indicated below ready to hand):

  • Enter all key data concerning the natural or legal person.
  • Print out a form for the PostIdent process and take it the post office for identification purposes or upload an electronic copy of your passport in the HKNR.
  • Upload a scan of your Handelsregisterauszug (Commercial Register extract(s)).
  • If applicable: Download the power of attorney form for account holders or vendors, complete it and then upload the completed form in the HKNR.

Find a quick user guide with detailed information concerning the HKNR registration process on the HKNR homepage.

Steps for disclosure with Guarantees of origin (GO)
Steps for disclosure with guarantees of origin (GO)
Source: Umweltbundesamt

Information for electricity grid operators

The  HKNR obtains power generation data from grid operators. Please note that the strict policy in this regard is “Don’t call us, we’ll call you.” In other words, grid operators should not take the initiative to either contact the HKNR or supply it with any data, without being expressly instructed to do so. For information as to how communication with grid operators is carried out, go to Downloads for grid operators ("Downloads", "Netzbetreiber"). For our initial contact with grid operators, we use the data from the database known as the BDEW-Codenummerndatenbank.

Find further information concerning implementation of the HKNR in the user manual downloaded from edi [at] energy [dot] Datenformate Strom & Gas (which was promulgated by Bundesnetzagentur advisory no. 33 of 02.04.2012 and went into force on 01.10. 2012; the current version, 2.1, went into force on 01.04.2014). A description of the HKNR process is available under HKNR FAQs (in German) as well as process flow diagrams.

The designation of the HKNR dataset for exchanging EDIFACT messages with grid operators is as follows:

GLN: 4399902157025
E-mail: edifact(at)


Regulations governing the HKNR

The UBA’s Herkunftsnachweisregister (German acronym: HKNR) went into operation on 1 January 2013. The latest Herkunftsnachweis-Durchführungsverordnung (Guarantees of Origin Implementing Ordinance) and the Herkunftsnachweis-Gebührenverordnung (Guarantees of Origin Fees Ordinance) entered into force on 21 November 2018.


Establishment of the HKNR at the UBA is governed by Section 55(4) of the Renewable Energy Sources Act (EEG) and by Verordnung über Herkunftsnachweise für Strom aus erneuerbaren Energien (Herkunftsnachweisverordnung – HkNV) of 28 November 2011, which was published in the Bundesgesetzblatt on 8 December 2011. For further information contact the HKNR office.


Recognition of foreign guarantees of origin

Results of a study for individual countries

The results of the research project, the summary and questionnaire of the project can be found in the tab "GO recognition" in the download section below.



Here you can download documents about information, events and forms concerning the Register of guarantees of origin and the Register of guarantees of regional origin. For more downloads (in German) see the German-language page.