GPKE and MaBiS: Market Communication for New Energy Suppliers
GPKE and MaBiS are the messages used in Germany to register customers and settle volumes. Supplier, grid operator, and metering operator send them as EDIFACT. If you don't run that, you can't sell electricity. This is the overview from six utilities I founded myself.
GPKE: Business Processes for Electricity Customer Supply
GPKE was issued by the Bundesnetzagentur (German Federal Network Agency) as a binding ruling to guarantee uniform processes between suppliers and grid operators. It governs in particular:
- Supplier switches with clear deadlines (max. three weeks processing time)
- Registrations and deregistrations upon move-in, move-out, insolvency
- Master data changes (address, bank details, tariff switch)
- Correction processes for faulty supply
- Surplus and shortfall settlement based on profile/load-profile metering
Every step is documented by an EDIFACT message, from application to confirmation. Missed deadlines lead to automatic cancellations and must be remedied with correction processes.
MaBiS: Balancing Group Settlement for Electricity
MaBiS governs how volumes between balancing groups are settled. At its core are the monthly balancing group settlements by the ÜNB (transmission system operator), the surplus/shortfall volumes between suppliers and VNB (distribution system operator), and the reporting to the BNetzA. Key components:
- Transmission of load profiles and load curves via MSCONS
- Calculation of the balancing group balance with tolerance bands
- Settlement of balancing energy under the AEP procedure
- Correction processes for retroactively reported metered values
- Reporting of market processes via REMADV and INVOIC
EDI@Energy: The Technical Layer
Technically, GPKE and MaBiS live within the EDI@Energy standard. The BDEW (German Association of Energy and Water Industries) maintains specifications, schemas and version levels. The most important message types:
The messages are exchanged between market partners via AS2 or AS4 (web service). Each message is uniquely addressed with market partner IDs (BDEW or EIC).
The supplier switch
The most frequent GPKE process is the supplier switch. The workflow in practice:
Most common sources of error: incorrect market locations (MaLo) or metering locations (MeLo), incomplete authorization, switch date on a weekend or public holiday (not permitted).
Version Management and Updates
The BDEW issues new versions of the EDI@Energy schemas annually. On average 1-3 major releases per year – usually with effective dates of 1 April and 1 October. Those who neglect version updates risk:
- Rejection of all market messages by VNB and ÜNB
- Delayed supplier switches and settlements
- Complaints and contractual penalties from end customers
- In the worst case: temporary suspension of the ability to supply
Recommendation: Begin testing at least 6 weeks before the effective date. MaKo service providers usually offer sandbox environments – use them actively.
Frequently asked questions
What do GPKE and MaBiS mean?+
GPKE stands for 'Geschäftsprozesse zur Kundenbelieferung mit Elektrizität' (business processes for electricity customer supply) and describes all market processes around supplier switching, registration and deregistration, master data maintenance, and surplus/shortfall volumes. MaBiS means 'Marktregeln für die Durchführung der Bilanzkreisabrechnung Strom' (market rules for balancing group settlement for electricity) and defines the settlement logic between ÜNB, BKV and supplier. Both are binding rulings by the Bundesnetzagentur and are technically implemented in EDI@Energy messages.
Which EDIFACT message types are central?+
The most important messages are UTILMD (master data and registrations/deregistrations), MSCONS (metered values), INVOIC (invoices), REMADV (remittance advices), CONTRL (acknowledgement of receipt) and APERAK (application error message). Each message follows an EDIFACT format with clearly defined segments and data fields. Versions are published centrally by the BDEW and must be implemented on time.
How does a supplier switch under GPKE work?+
The new supplier sends a UTILMD registration to the responsible distribution system operator. The latter checks master data, market role and switch dates and responds within three working days with confirmation or rejection. Upon confirmation, deregistration with the old supplier is also carried out via UTILMD. All confirmations must be available at least 21 working days before the planned switch date, otherwise the switch is postponed.
Which deadlines apply to market communication?+
Master data and registration/deregistration processes must be handled within a few working days (typically 1-3 working days depending on the process). Metered values are transmitted monthly and, for balancing group settlement, in quarter-hour intervals. Payment of invoices is due within the agreed deadlines – usually 14 or 30 days. The rulings of the BNetzA define the deadlines bindingly.
Do we need a GPKE certification?+
A formal 'certification' in the sense of a state auditing body does not exist. However, proof is required that your market communication complies with the rulings of the BNetzA – either through audit confirmation from your IT service provider or through your own testing in market simulations. The BDEW publishes schemas against which testing is done. ÜNB and VNB carry out acceptance tests before go-live.
What does market communication cost?+
In-house development is only worthwhile from very large volumes. It is common to connect to a MaKo service provider (Lacroix, regiocom, Kisters, Wilken, Schleupen and others) with setup costs of 10,000-50,000 EUR and ongoing fees of 0.05-0.2 ct/kWh or flat rates per metering point. In addition there are maintenance and version update costs – typically 1-3 times per year.
How do the processes change with the smart meter rollout?+
With the rollout of intelligent metering systems (iMSys), metering-data-based processes gain importance. New message types such as ORDERS, ORDRSP and higher granularity in MSCONS require adjustments in the IT systems. In addition, surplus/shortfall settlements become more accurate and faster. Utilities must actively track version changes – delays lead to market blockages.
What happens with erroneous market communication messages?+
Recipients respond with APERAK (application error) or CONTRL (technical error). These messages contain specific error codes. Anyone who does not fix errors within a few days loses market processes: supplier switches fail, balancing group entries are rejected, settlements are delayed. Systematic errors risk exclusion from the market.
Implement GPKE/MaBiS Safely
I've taken six utilities through go-live of market communication. The service provider, the tests, the version changes. On the first call we look at what's next for you.