Background
#For the PV export limit in Zug, the following has applied in the WWZ grid area since 1 January 2026: new systems must be planned so that no more than 70% of their DC module capacity is exported to the grid.
The requirement also applies to an existing system when its inverter is replaced. It limits export to the grid, not consumption in the building or charging a battery in between. WWZ identifies configuration in the inverter or energy-management system (EMS) as the technical route. This is not a blanket cantonal rule: outside the WWZ grid area, the responsible distribution network operator determines its own process and technical requirements.
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What matters in the canton of Zug
#The grid area determines whether the rule applies. The WWZ requirement applies in its own grid area from 1 January 2026, not automatically to every address in Canton Zug; the responsible distribution network operator must therefore be confirmed before detailed planning.
DC module capacity is the decisive value. WWZ limits export capacity to 70% of the modules’ DC rated capacity; a larger module area is not prohibited, but the export peak must be handled separately in the design.
An inverter replacement is a specific trigger. WWZ also applies the 70% rule to existing systems when a new inverter is installed; for a refurbishment, configuration must therefore be included in the technical quotation.
The limit is intended to reduce midday peaks, not prevent solar use in the building. WWZ identifies the inverter and EMS as implementation points; self-consumption through a heat pump, boiler, wallbox or battery remains possible and belongs in load planning.
WWZ quantifies the possible yield reduction. For export limited to 70%, WWZ gives a maximum of 3% of annual yield; that figure concerns curtailment, not the project’s overall economics.
Existing systems without an inverter replacement are not automatic cases. WWZ explains that further implementation and timing for existing systems are set by the respective grid operators; an existing system should therefore not be reconfigured pre-emptively without a specific request.
The process in six steps
#Tick off for your project
Confirm the grid area
before sizing anything, check whether the property is in the WWZ grid area. At an address outside that area, the requirements of the local distribution network operator apply, not the WWZ 70% rule automatically.
Classify the system case
new PV systems and existing systems with an inverter replacement fall within the WWZ case described since 1 January 2026. Record the replacement not merely as service work, but as a design change.
Separate capacity values
show the modules’ DC rated capacity and export capacity limited to 70% distinctly in the diagram, quotation and documents for the grid process.
Choose the implementation
decide with the electrical contractor whether the limit is configured in the inverter or the EMS. The chosen solution must reliably keep the export limit without unnecessarily blocking self-consumption.
Include loads
capture the heat pump, boiler, wallbox and battery storage in the EMS concept. These loads are not the export limit itself, but can use PV electricity in the building when grid export reaches its 70% boundary.
Document the configuration and verify it before commissioning
compare the limit set in the inverter or EMS with the modules actually installed. Repeat the same check for any later inverter replacement.
Checked for your roof, not just read up on
How much funding does your roof get?
With your address we calculate the one-off payment, your canton’s incentives, tax deduction and regional feed-in tariff for your system.
Free and non-binding · no unsolicited calls
Rather talk directly? +41 78 615 90 58
Frequently asked questions
#Sources
#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.