Short answer
What you need to know first.
In Aargau, a battery is mainly a serious option when not enough solar power is consumed directly during the day, relevant loads exist in the evening or at night, and the metering and connection concept is prepared cleanly with AEW or the responsible grid operator. For single-family homes, multi-family buildings and commercial properties, the goal is therefore not the largest battery, but a size that realistically reflects PV generation, self-consumption, peak loads, later wallboxes or heat pumps and possible self-consumption models.
Important
This page provides general guidance for PV battery storage in Aargau. It does not replace property-specific technical planning, grid-operator assessment, electrical or fire-safety review, or legal, tax or incentive advice. Tariffs, feed-in conditions, incentive programmes and grid-operator requirements must be checked directly for the specific property and current date.
Decision points
What determines the right path.
The load profile comes first. A household with high evening consumption, heat pump or e-mobility has different requirements from a business with daytime loads. A battery can shift self-consumption, but it does not replace a proper load analysis and energy management.
Battery size must match the PV system. Too small has little effect, too large often remains underused or worsens economics. A sensible approach compares PV-only, battery, wallbox, heat pump and possible later expansion.
The AEW metering and connection concept belongs before installation. AEW distinguishes metering types for self-consumption, feed-in and production metering and requires a connection request before construction. With batteries, multiple consumers or ZEV/vZEV, the metering concept can matter more than pure battery capacity.
Backup power is not a standard feature of every battery. Many systems increase self-consumption but do not supply selected loads during a grid outage without additional backup functionality. Anyone wanting backup power must separately assess switching, load priorities, grid separation and electrical planning.
Incentives and Pronovo do not cover the same item. The national one-time payment relates to photovoltaic systems; batteries must be checked separately against current cantonal, municipal or sector-specific programmes. An incentive statement does not replace a current application check.
Sequence
How the project stays cleanly managed.
- 1
Record the current situationannual consumption, daily load, heat pump, boiler, wallbox, commercial loads, existing meters, house connection, roof area and planned PV capacity. Without these data, every battery size is only an assumption.
- 2
Calculate variantsPV without battery, PV with smaller battery, PV with larger battery, battery with wallbox or heat pump and possible later ZEV/vZEV use. Self-consumption, residual grid purchase, feed-in, investment and operation must be assessed together.
- 3
Clarify the grid-operator pathresponsible grid area, technical connection request, metering type, meter order, production or surplus metering and commissioning documents with AEW or the local grid operator before material is ordered definitively.
- 4
Define the technical storage conceptbattery location, fire-safety interfaces, inverter or hybrid concept, communication interfaces, energy management, backup option and space reserves for later loads.
- 5
Prepare commissioning and follow-upsafety certificate, measurement and test protocol, grid-operator documents, Pronovo data for the PV system, monitoring and initial operating data. Only operating checks show whether battery and loads work together correctly.
Checklist
Questions to settle before the quote.
- Check load profile, PV yield and battery size together before quoting
- Clarify AEW metering type, connection request and later extensions early
- Do not confuse storage with backup power: assess backup capability separately
- Plan self-consumption, ZEV/vZEV, wallbox and heat pump as one system
FAQ
Common questions on this topic.
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.
- AEW: producing electricity - process and documents (connection application, metering)AEW Energie AG (responsible grid operator)
- Canton of Aargau: funding of measures (energy)Canton of Aargau, Department of Construction, Transport and Environment
- Pronovo: one-time remuneration (EIV) for photovoltaicsPronovo AG (federal)