MaKo – How the Players in the Unbundled German Energy Market Communicate

The digitalization of the German energy industry encompasses a wide range of business and practical areas. One key initiative is to ensure that data can flow smoothly and securely between all parties in the electricity and gas sectors. This involves standardised processes to make sure that business transactions are time and cost efficient. A significant part of the various standardisation initiatives involves defining and regulating how information is electronically sent and received between the many players in the power industry; known as market communication (MaKo, from the German Marktkommunikation). This encompasses a long list of processes, is complex to put into practice and involves myriad players. At the same time, we also need to clearly identify and define market roles and market players to enable them to communicate with each other.

This guide aims to demystify this complex world for you. Read on for a clear overview of the who, how and why of market communication in the German energy industry.

The processes that require this sharing of information have their roots in the liberalisation of the German energy market.

Over time, market players have adopted common processes, formats and transmission rules to enable automated, efficient communication with their counterparts.

The journey started in 2006, with the introduction of business processes to supply customers with electricity. These are known in German as GPKE. They were followed by similar processes for the gas market (shortened in German to GeLi), rules to balance gas and electricity supply (shortened in German to GABi Gas and MaBiS respectively) processes for measuring consumption (WiM) and Redispatch, which covers balancing mechanisms to ensure grid stability.

There are regular amendments to these processes, formats and transmission rules to meet the developing needs of the energy market.

Market communication is critical to running a functioning, open energy market and securing power supply. We have since celebrated over 15 years of market communication, all supported by the cross-association working group edi@energy.

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The liberalised energy market is continuing to develop as legislation changes, the regulatory framework grows in scope and there are new procedures for defining rules and processes.

Setting policy and consultation periods

Two of the most important instruments for the BNetzA are formal procedures to set and consult on policy. These formal procedures allow them to define and implement the terms under which players may access the market. The Federal Network Agency (BNetzA) drafts the policies in consultation with representatives for the various market players. These are published during a fixed-length public consultation period, during which anyone can comment on them. BNetzA then evaluates this input and may amend policies as a result. This ensures that the market players are still being heard in the very necessary work of regulating the market and creating effective processes.

A who’s who of regulators and their specific roles (What is BMWK/ BNetzA/ BDEW/ DVGW/ edi@energy?)

The following are key players in defining the processes in the German liberalised energy market and the corresponding market communication.

In the main, communication is in an EDIFACT  format. Some Redispatch 2.0 processes (adopted 2021) use XML. The XML structures follow ENTSO-E specifications.

edi@energy publishes the message types for the above processes, while data formats for the gas sector (GaBi Gas) are published by DVGW's wholly-owned subsidiary, DVGW Service & Consult GmbH.

GPKE / GELI

GPKE stands for Geschäftsprozesse zur Kundenbelieferung mit Elektrizität (business processes for supplying electricity to customers) while GeLi Gas stands for Geschäftsprozesse Lieferantenwechsel Gas (business processes for switching gas supplier). Both describe the main processes and corresponding electronic data interchange for switching supplier.

The business processes for both the above involve:

• Balancing Group Manager (BKV)
• Supplier (LF)
• Grid operator (NB)
• Meter operator (MSB)
• Transmission system operator (ÜNB)

They encompass the following tasks:

• Terminating old contract (done by the new supplier on behalf of the customer)
• Supply end date (either due to switching supplier or another reason for cutting supply)
• Supply start date (either due to switching supplier or another reason for beginning supply, e.g. a new-build)
• Substitute supply (so consumer still has an energy supply if new supplier is not known– as regulated by safety-net and substitute supply clause §38 of EnWG)
• Reading meter and passing on consumption level
• Grid usage billing (billing of grid usage fees to grid user)
• Updating and sharing master data
• Business data request (request for master data or readings from market or measuring stations)

MaBiS / GaBi

MaBiS is a set of regulations for managing the balancing group, balancing rules and balancing group settlement for the electricity sector. GaBi Gas is the equivalent for the gas sector.

These involve the following players:

• Balancing Group Coordinator (BIKO) / Market Zone Manager (MGV)
• Balancing Group Manager (BKV)
• Supplier (LF)
• Grid Operator (NB)
• Transmission system operator (ÜNB) /(FNB)

MaBiS encompasses the following processes:

• Data exchange processes for balancing zones(registration/deregistration of balancing zones, balancing group allocation)
• Data exchange processes for time series (activating/deactivating MaBiS metering points, reconciling and submitting network time series)
• Data exchange processes between grid operator and supplier (or transmission system operator) (exchanging/transmitting standardised profiles, bands and profile definitions)
• Data exchange processes between transmission system operator and supplier for supplier time series and clearing list
• Data exchange processes for balancing totals time series
• Data exchange processes for delta time series transfer
• Data exchange processes for settlement totals time series
• Exchange balancing energy prices
• Data exchange processes for daily balancing zone totals time series
• Data exchange processes for daily balancing group totals time series
• Data exchange processes for REDISPATCH balancing

GaBi Gas involves the following processes:

• Declaring quantity
• Standardisation
• Changing capacity
• Declaration lists
• Declaring surplus/ shortfall

WiM

WiM stands for Wechselprozesse im Messwesen and describes the central processes and associated electronic data interchange involved in metering, if these are not otherwise defined in GPKE. These essentially involve switching the metering point operator and changing metering equipment. The processes are slightly different for electricity and gas.

WiM involves the following players:

• Meter Operator (MSB), Default Meter Operator (gMSB)
• Grid Operator (NB)
• Supplier (LF)
• Transmission system operator (ÜNB)
• Energy service provider to consumer (ESA)

WiM encompasses the following processes:

• Terminating a metering point
• Start metering point operation
• End metering point operation
• Obligations as default meter operator
• Supplementary processes for metering point switchover:
  • Change device and
  • Transfer device
• Changes to measuring stations, whether conventional measuring devices (kME), modern measuring devices (mME) or intelligent measuring systems (iMS), encompassing installation, upgrade and calibration
• Installing a modern measuring device into an existing measuring station
• Installing an intelligent measuring device into an existing measuring station
• Billing for metering point
  • Sending price list data for an intelligent or modern measuring device
• Billing for an intelligent or modern measuring device
• Overarching processes
  • Troubleshooting and error resolution for a measuring station

MPES

MPES stands for Marktprozesse für erzeugende Marktlokationen Strom (processes for generating market locations, electricity) and define the processes relevant to direct marketing. The processes apply to any electricity generator, whether CHP or renewable energy, from which the power can be marketed in full or part straight to the consumer, i.e. the consumer can change suppliers. We differentiate between plants who must sell their power through direct marketing, and those who may.

If a situation arises for which there is no provision in MPES, the rules in GPKE and WiM apply. In this case, substitute:

• generation for supply
• generate power for consume power
• generator for end user

Players:

• Balancing Group Manager (BKV)
• Supplier (LF)
• Network Operator (NB)
• Meter Operator (MSB)
• Transmission system operator (ÜNB)
• Generator (EZ)

Processes

• Registration for direct marketing
• Cancellation
• Begin supply
• End supply
• Auditing an EEG market location with an obligation to full direct marketing which only has one supplier

HKNR

Processes pertaining to the guarantee of origin register involve EDIFACT communication with the Federal Environment Agency.

Players

• Grid Operator
• German Environment Agency (Umweltbundesamt, shortened to UBA)

Processes

• Requests from German Environment Agency for master data or meter readings
• Grid operators sharing master data with German Environment Agency
• Sending meter readings to power generators
• Cancelling subscription-based transfers of records or readings

Redispatch 2.0

Players

• Operations Officer (EIV)
• Data Provider (DP)
• Power Generator Operator (ANB)
• Grid Operator (NB)
• Supplier (LF)
• Balancing Group Manager (BKV)
• Technical resource operator (BTR)
• Transmission system operator (ÜNB)
• Balancing Group Coordinator (BIKO)

Significant processes

• Exchanging master data records, planning records and non-usage (EIV-NB)
• Transmitting and forwarding meteorological data
• Determining and reconciling downtime relevant for accounting
• Changing balancing or accounting model
• Redispatch balancing processes

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6. Data formats

With the exception of the Redispatch 2.0 processes introduced in 2021, EDIFACT is the syntax used in market communication. Specifications are defined and published by edi@energy and include the following EDIFACT formats:

• UTILMD (utilities master data message) – exchanging data on customers, contracts and meters
• UTILTS (utilities time series message) – Transmitting formula for calculation
• MSCONS (metered services consumption report message) – meter readings, energy quantities
• ORDERS (purchase order message) – orders
• ORDRSP (purchase order response message) - purchase order response
• QUOTES – quotations
• REQOTE (request for quote) – request quotation
• INVOIC (invoice message) – invoices for grid and energy services
• REMADV (remittance advice) – remittance advice
• COMDIS (commercial dispute message) – helps clarify why an invoice has been rejected
• PRICAT (price catalogue message) – price lists for balancing and metering services
• IFTSTA (status of transport) – message tracking
• INSRPT (inspection report) –used to communicate technical faults in a measuring station or known by an operator
• APERAK (application error and acknowledgement message)
• CONTRL – confirms syntax and successful sending

The gas sector uses further formats, as defined by DVGW Service & Consult GmbH. These include:

• ALOCAT (based on ORDRSP) – Information on quantity taken
• IMBNOT (based on ORDRSP) – Balance/imbalance message to balancing group coordinator or grid operator.
• SLPASP (based on ORDCHG) – supplies parameters to calculate allocation
• SSQNOT (based on ORDRSP) – Reporting excess/shortfall quantities
• TSIMSG (based on UTILMD) – Declaration list for balancing group management in the gas sector

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7. Communication

The technical side of how the market communicates is set out in Regelungen zum Übertragungsweg (communication method/protocol regulations) and Allgemeine Festlegungen (general provisions), both on the documents page of the edi@energy website. The document specifies the security and protection mechanisms required for electronic data exchange in regulated processes between market partners in the German energy industry.

Communication methods and/or protocols include AS2, e-mail via SMTP, SFTP and REST. AS2 and e-mail over SMTP are used in a number of energy market processes, whereas SFTP and REST are only permitted in Redispatch processes. Communication should always be encrypted and signed.

An important aspect of communication in the German power industry is having a single point of contact. This means that there is only one set of contact details per member ID. A grid operator in the electricity sector, for example, is only able to specify one e-mail address.

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8. Format changes

The processes, formats and transmission protocols are not static. They are constantly being updated to reflect changing regulations and requirements. These changes and extensions come into effect at scheduled points throughout the year.

Changes apply equally to all market participants. To ensure that everyone has the same understanding of current regulations, processes and formats and that there are not several different versions in circulation, changes come into effect on fixed dates.

Unless otherwise specified, changes to format, processes or regulations only come into effect on either the 1st April or 1st October of a given year. All market participants must have switched to the new formats, processes etc. by the set deadline as the older versions immediately become invalid and may no longer be used.

The amendments are published by the BNetzA, or edi@energy, on behalf of BNetzA. There is always a consultation phase beforehand which lets participants have their say.

General

1. 1. Which changes apply with MaKo 2023?

• AS4 communication replaces AS2 and email communication in the electricity sector.
• All market participants need to set up a new connection to each of their communication partners.
• AS4 communication to be encrypted with ECC Brainpool (elliptic curve cryptography).
• Certificates are used within the smart meter public key infrastructure (PKI).
• Participants will need to obtain new certificates.
• MaKo to become part of the smart meter public key infrastructure (SM-PKI).
• Private keys must be secured in the hardware security module (HSM).
• Take a look at this SEEBURGER AS4 blog article to discover more.

Dates

2. Is the October 2023 deadline likely to be postponed again?

• So far, there has been no talk of further delaying MaKo 2023.

3. Will the migration period be extended to April 1, 2024?

• The AS4 migration period will not be extended.

4. The technical implementation process is due to run from October 1, 2023 to March 31, 2024. Can I start using the new communication format before October 2023?

• You may enter mutual agreements with partners to use the new transmission path before October 1, 2023. However, you may not discriminate in any way against partners who do not introduce the format ahead of schedule.

5. What happens if I’m not able to communicate via AS4 as of October 1, 2023? Can I refer to the "transition period" until March 31, 2024?

• There is no “transition period.” There is a migration period from October 1, 2023 to March 31, 2024. All market participants are required to be able to communicate via AS4 starting October 1, 2023. SEEBURGER does not know how the BNetzA will deal with market participants who do not meet the deadline.

AS4 profile

6. What do I need to switch to AS4?

• You need an AS4 adapter that supports ECC Brainpool. The SEEBURGER adapter already supports this type of encryption.
• You need a hardware security module (HSM) to generate and store private keys.
• You need new certificates from the Federal Office for Information Security’s smart meter public key infrastructure.

7. Where can I find details of the AS4 profile? Is this available to view anywhere?

• You can find information on the AS4 profile for MaKo on the edi@energy page.

8. Does AS4 use the push or pull method?

• MaKo only uses the push method.

9. Is the URL in the certificate the AS4 address or web address where I can get the AS4 parameters?

• The URL is the same as the AS4 address used for communication.

10. When can I consider a file „delivered“ through AS4? Is there a time stamp I can refer to?

• Your file has been successfully transferred via AS4 if you receive a synchronous, non-repudiation receipt (NRR).

11. As with smart meters, do I have to provide a separate host name for each connection?

• Each endpoint, i.e. each individual partner ID, requires a hostname.

HSM

12. What is HSM?

• HSM is an acronym for Hardware Security Module. This is used to generate and store private keys.

13. Can my company only use one HSM?

• A company can use multiple HSMs. There are no restrictions to the number you can use.

14. Can I use the same HSM for smart meter communication and MaKo?

• Yes, you can use the same HSM. You can find more details in the BSI Certificate Policy (CP) for Smart Metering PKI version 1.1.2.

15. What HSMs can I use?

• From what we know so far, you can use any HSMs that have already been approved for SM-GW communication by the BSI.

16. Can I implement and use one HSM for multiple organizations and customers or are there scenarios that require two or more HSMs?

• You can use one HSM for several organizations and customers.

17. From now on, will every MaKo process via AS4 access my HSM in order to retrieve the certificate information?

• All cryptographic operations that need a private key take place within the HSM.

18. The CP was published by the BSI in March 2023. It describes that no HSM and no process can be streamlined for "smaller scenarios." How exactly is that to be interpreted, since some passages of the CP also contradict each other?

• Contradictory passages from the CP related to storing the keys for communication with the sub CA, and not for market communication, will be corrected.

19. Why did SEEBURGER opt for an HSM instead of an alternative cryptographic module (smart card or server)? According to the definition, passive external market participants (EMT) do not fall under security level 2 but only under security level 1, which means that using a certified HSM is not mandatory?

• For the MaKo AS4 service, SEEBURGER opted for an HSM certified for the smart meter PKI because we want to provide our customers with proof of compliance with the requirements for the cryptography module at any time. An HSM certified according to the PKI specifications fulfills the requirements and can be proven by the certification and the manufacturer's declaration.

Certificates

20. Which sub CAs can I use for MaKo and from when?

• Find more information on all sub CAs in this list from the Federal Office for Information Security (BSI): Sub CA list.

21. Is there a specification or a process on how to apply for the certificates?

• You must follow a specific process to apply for certificates as defined by the BSI.
• You can find the relevant BSI documents in the list below:
  • Certificate Policy (CP) for Smart Metering PKI
  • BSI TR-03109-4
  • BSI TR-03116-3

22. Can the TLS-SSL certificate for an incoming AS4 https endpoint come from a free CA, or does it need to come from the BSI PKI?

• You must use a TLS certificate from the smart metering public key infrastructure (SM-PKI).

23. Do I actually need a separate AS4 certificate for each role or division? This field has always been optional for AS2?

• The certificate policy for the smart meter PKI stipulates an individual AS4 certificate for each MP-ID – i.e. also for each division – as the MP-ID must be maintained in the certificate.

24. Will there be permanent AS4 certificates? Or will they also expire after a certain period and need to be re-obtained?

• From what we know so far, the AS4 certificates will expire after two years.

Migration scenarios

25. What can I do if market participants are still not able to use AS4 after October 1, 2023, or if my own company has not migrated to the new messaging protocol yet?

• There are no clearly defined rules or consequences for this scenario. However, it is obligatory to have fully migrated by March 31, 2024 at the latest.

26. How is the migration phase organized? Who reports to whom, and when?

• The BDEW has issued recommendations for dealing with migration. However, essentially “the market has to organize itself”. You are therefore expected, to plan time for queries and delays into your project plan.

27. Where can I find the BDEW recommendations for the migration period?

• You can find the BDEW application help “introductory scenario for migrating to AS4” on the Edi@Energy website.

28. What is the process for automated migration to AS4 after the test period, or after a request for migration has been issued?

• The conversion service sends a conversion request to the partner. Your partner confirms the request, after which you can use AS4 to communicate in both directions.

29. Can I completely delete email communication data during the migration period?

• Please ensure a fallback option to email in the unlikely case that an error occurs during the migration period of October 2023 to March 2024.

30. Can I still maintain email communication after migrating to AS4? If so, would you recommend doing so?

• Incoming email communication should be kept open during the migration period. However, we recommend monitoring these emails so that market participants who have supposedly switched to AS4 do not send them to the mailbox. As of April 1, 2024, according to BNetzA specifications, you must not communicate via email anymore and hence the mailbox shall be closed down.

31. 31. What if a market participant can’t be contacted via AS4, i.e. retry continues to fail?

• If the connection fails even after repeated attempts, the sender receives an error notification. However, if only a single transmission fails, this does not mean that the whole market communication has been disrupted!

32. When will there be a switch back to email?

• A temporary switch back to email communication can only be done if one of the two partners has identified a disruption in the market communication and has also declared it as such. This temporary email communication will be carried out in mutual agreement and as soon as the fault has been rectified, the system will be switched back to AS4 in a likewise mutual agreement. This regulation applies to the changeover phase.

Other

33. Have there beeninteroperability tests with other manufacturers?

• SEEBURGER is in contact with other manufacturers and service providers as well as via various working groups, such as BDEW, EDNA. The tests are ongoing.

34. Are there exemptions for certain market participants or limitations for SMEs?

• No, there are no exemptions.

35. Where is the data decrypted?

• In the HSM.

36. Why are there two versions of the regulations for the transmission paths? Which one is valid?

• Both will be valid.
• RzÜ from version 2.x regulates the AS4 communication for MaKo in the electricity sector.
• RzÜ from version 1.x regulates the communication for MaKo in the gas industry which has not yet changed, Redispatch 2.0.

37. What are the e rules for the gas industry?

• RzÜ 1.x continues to apply to the gas industry.We currently have no information when they are implementing AS4.

38. 38. I found this in the latest BDEW documents: “Deadlines for the market migration: Within six weeks after the start of the migration period or parallel operation, all market partners should have migrated their communication to AS4 by migrating communication with all market partners to AS4 one after the other using the “Change of transmission path” service.” Is the migration period just six weeks long rather than half a year? Or is this statement no longer applicable?

• The application help is to be seen as a recommendation. The migration period runs until March 31, 2024. However, you may consider migrating as many partners as soon as possible.

39. Will there be a central address service?

• The German BNetzA is not planning to have a central address service for retrieving AS4 communication data. Therefore, you must separately store and continuously update all data per MP-ED for each of your market partners.

40. The TSOs have already announced that the exchange of schedule data must also be exchanged via AS4 as of 2024. Is this also part of the MaKo Cloud Service for AS4 delivery?

• At the technical level of AS4 communication, the SEEBURGER AS4 Service also supports the requirements for AS4 communication in schedule management. However, since the AS4 service is designed on the basis of the specification for MaKo in the electricity sector and the requirements for schedule management were not known at this time, this use case is not yet in scope.

41. The 24-hour supplier change process is currently in consultation. What impact does this have on market communication?

• The effects on MaKo are not yet known, as the individual process steps have not yet been defined. However, this has no effect on today's MaKo.

Connection to the SEEBURGER AS4 Cloud Service

42. How do I connect to the AS4 cloud service?

• Connect via AS2 or a REST service.

43. Why should I connect via AS2 or REST only, excluding email and any other protocol?

• The connection specifications are based on the specifications of the BSI CP 1.3.3.4 external market participants: "With such a system structure, care MUST be taken to ensure that the data exchange between the service provider and the client has a security level comparable to the security mechanisms defined in [TR-03116-3].” TR-03116-3 refers to TR-02102, which states what is “secure” and for how long from the BSI’s viewpoint.