Short answer
What is a vZEV for a photovoltaic system?
A virtual self-consumption community in Basel-Stadt suits existing buildings when IWB confirms the grid topology and the PV system reaches at least 10% of the connection capacity. Existing IWB meters can often remain in use. Before operation, a complete IWB application, the legal organisation of the community and clear arrangements for metering and billing are required.
Important
As of 23 July 2026: a vZEV across multiple addresses in the IWB grid area is possible only if IWB confirms the specific grid topology. The 10% threshold alone is not sufficient. The technical check, complete registration and tenancy or ownership arrangements must be brought together before commissioning.
At a glance
Key figures: Virtual self-consumption PV Basel-Stadt
| Metric | Value |
|---|---|
| Since when? | In the IWB grid area since 1 January 2025 |
| Minimum output | At least 10% of connection capacity |
| Multiple addresses | Have IWB check grid topology in advance |
| Registration | Submit complete; IWB specifies a three-month processing period |
| Metering | Existing IWB meters are often usable |
Decision points
What determines the right path.
A virtual self-consumption community does not automatically join neighbouring houses. Since 1 January 2025, IWB permits it only where the topology of the connection lines links the intended buildings; for multiple addresses, the IWB check using the actual addresses is therefore the first decision.
The minimum size is set by law: the system’s production capacity must equal at least 10% of the community’s connection capacity. ElCom assigns this threshold to Art. 17 para. 1 EnG in conjunction with Art. 15 EnV; a design without the connection capacity is therefore incomplete.
A conventional and a virtual self-consumption community require different alterations. According to IWB, a vZEV uses the grid operator’s existing meters, so existing multi-family or single-family homes often need no electrical-installation conversion. This does not replace a review of the metering and connection concept.
Registration is a genuine project step: IWB requires a complete application for both conventional and virtual communities. Incomplete submissions are returned for completion; IWB processes complete applications within the statutory period of three months.
Technology and contractual arrangements must fit together. For existing buildings, IWB points to a tenancy addendum and, for condominium ownership, to an amendment of the regulations. Anyone planning metering and billing should settle these documents with the owner or management before commissioning.
The benefit comes from local use, not from the label. IWB describes direct use of solar electricity within the property for both models; whether the arrangement is economical also depends on generation, consumption profile, metering, billing and the meters actually participating.
Sequence
How the project stays cleanly managed.
- 1
Define the property and participantsrecord buildings, addresses, existing meters, connection capacity and PV area. For multiple buildings, IWB needs these exact addresses for the vZEV check.
- 2
Check the PV minimum outputcompare the planned photovoltaic production capacity with the community’s connection capacity. The statutory threshold is 10%; if it is not met, this model is unsuitable.
- 3
Clarify grid topology with IWBsubmit the intended addresses for review before promising to connect multiple buildings or arranging metering. IWB gives no guarantee of the connection without a check.
- 4
Set the metering and operating modelbased on the existing setup, decide whether a vZEV using existing IWB meters or a conventional community with its own metering infrastructure fits. Document responsibilities for data, billing and participant changes.
- 5
Prepare contracts and regulationsin existing buildings, a tenancy addendum, and for condominium ownership, an amendment to the regulations, belong before operation begins. The technical registration does not replace this internal basis.
- 6
Submit the complete registration on timeuse IWB’s form for conventional or virtual communities and submit all information completely. IWB specifies a three-month processing period and generally commissioning at the start of a month with at least three months’ lead time.
Checklist
Questions to settle before the quote.
- Have IWB check the grid topology for multiple addresses before planning
- Assess the PV system’s 10% minimum output against the connection capacity
- Submit a complete IWB application with at least three months’ lead time
- Clarify a tenancy addendum or condominium regulation before operation
FAQ
More questions: Virtual self-consumption PV Basel-Stadt
Sources
Official sources & references.
The responsible authorities are decisive. Always verify binding details – amounts, deadlines and conditions – for your specific property against the current status of the respective authority.