Decentralised supply models
The use of locally generated energy is a building block for a smart city and climate neutrality.
End consumers are free to choose their electricity supplier. Under certain conditions, decentralised supply models can offer them further options. End consumers can then potentially benefit from locally produced energy.
Uncertainty about future legal regulations
There is currently uncertainty regarding the scope of application of customer systems due to a ruling by the German Federal Court of Justice (BGH) from May 13, 2025. There has been no legal clarification of this to date. The BGH ruling is also significant for the tenant electricity models that have been available until now. We have compiled further information on how Stromnetz Berlin is dealing with the existing uncertainties in an overview.
Information sheet for customer systems
In German language only.
Customer system
Within the meaning of Section 3 No. 65 and No. 66 of the German Energy Industry Act (EnWG), a customer system is a customer-owned installation for the provision of energy which, unlike energy supply networks, is exempt from regulation.
Customer systems are typically installed in apartment blocks and take the form of tenant electricity constructs. This regulation is also applied to commercial enterprises and industry.
By connecting and operating a generating system within the customer system, the amount of electricity purchased from the general supply grid can be reduced if end consumers connected to the customer system opt to use the locally generated electricity. However, it is important to note that end consumers using the customer system still retain the right to freely choose their electricity supplier.
Operators of the customer system are obliged to ensure that the electricity is transmitted free of discrimination and without additional charges, so that the free choice of supplier remains unrestricted.
Tenant electricity
Tenant electricity is a supply model for end consumers. The electricity is produced directly on site – i.e. on, at or in a building (for example an apartment block or commercial building) – by a generating system.
The special feature here is that the electricity generated on site is used within the same building by the participating tenants or members of an owners' association. The electricity is distributed via the existing building installation without having to be routed through a separate distribution network.
Unlike electricity purchased from the distribution grid, some cost components can be omitted for electricity that is both generated and consumed on site. These include:
- the network charges
- network-based levies (for example the "KWKG" combined heat & power levy, the levy as per Section 19 of the Electricity Network Fee Regulation Ordinance (StromNEV))
- electricity tax and/or
- the concession fee.
Key features of tenant electricity at a glance
| Feature | Tenant electricity |
|---|---|
| Generating system | All types of generating systems possible (typically combined heat and power plants or photovoltaic systems) |
| Measurement technology |
Totaliser Tenant meter |
| Tenant electricity surcharge |
possible under certain conditions Application for tenant electricity surcharge |
| Legal basis |
Section 42a of the German Energy Industry Act (EnWG) |
| Standard measurement concepts |
Measurement concept 6 or |
| Contractual basis | Participants conclude a tenant electricity contract with the tenant electricity provider |
| Technical application (measurement concept) | We would ask you, or the installation company you have chosen, to use our customer portal |
| Registration of participants (network utilisation) | Please send your registration information to: [email protected] |
Information for operators of a tenant electricity model
General information
The ruling of the German Federal Court of Justice (BGH, May 13, 2025 [EnVR 83/20]) also has an impact on tenant electricity systems. Please note the information provided above on the new requirements for connection of customer systems in accordance with Section 3 No. 65 and No. 66 of the German Energy Industry Act (EnWG), which relate to the distinction between customer systems and the distribution network.
Successful implementation of a tenant electricity project requires a carefully coordinated approach. Please therefore discuss your plans with your installation company before submitting your application to Stromnetz Berlin.
Registration of a generating system or change to the measurement concept for a generating system (technical application)
First of all, please check
- whether your building is suitable for an electricity generating system (for example roof area available, orientation) and whether a tenant electricity model can be implemented
- or whether an existing electricity generating system can be used
Please have new electricity generating systems registered on our customer portal by your installation company. The installation company can also directly specify the measurement concept to match the desired supply model.
Please also have your installation company switch over any existing, already registered electricity generating systems to the desired supply model via the Change measurement concept section of the customer portal.
In addition, you must register your generating system in the market master data register if you have not already done so.
Registration of participants in the supply model (network utilisation)
As soon as your electricity generating system has been commissioned or successfully re-registered, please register the desired supply model for commercial processing. Commercial processing ensures that the necessary registration and deregistration processes for participants in the supply model are smoothly coordinated between you and Stromnetz Berlin.
Please send an e-mail to:
[email protected].
Should other end consumers decide to participate in tenant electricity while the system is in operation, please pass on this information immediately.
After clarifying the requirements and/or adding new participants, we can then perform the energy quantity calculation correctly and transparently.
Application for a tenant electricity surcharge
Due to legal requirements, the system operator must first submit an application before introducing a tenant electricity surcharge. Please use the tenant electricity surcharge application form for this.
Please send the completed, signed form and any required documents to:
[email protected].
Questions and answers
In the following, we have compiled frequently asked questions and the corresponding answers for your information. Feel free to contact us if you have any further questions about micro grids. Please use our e-mail address [email protected] for this.
Does Stromnetz Berlin provide the meters for micro grid users and what do the meters cost?
The electricity meters can be provide by Stromnetz Berlin.
The fee for the electricity meter can be found in our price sheet on the Responsible meter operator page.
I have a CHP and a PV system. Is a micro grid also possible with this combination?
It is possible to combine several generating systems. Please note that your electrician will coordinate the metering concept with us before building of the micro grid system.
Do all tenants have to use the micro grid?
No. Tenants are under no obligation to use it. Tenants who do not use it choose their own energy supplier.
Can Stromnetz Berlin also handle electricity billing for micro grid users?
No. We do not offer this service.
What is a micro grid subsidy?
The micro grid subsidy is a special subsidy under the Renewable Energy Sources Act (EEG) for electricity from solar power systems. You can find out more on the website of the Federal Network Agency (Bundesnetzagentur).