Fronius + myStrom

What Zerofy can do with Fronius and myStrom

In practice

• Solar mode switches your myStrom switch on when there’s surplus, following your priority order and minimum runtime. Smart mode instead runs for a set number of minutes within the hours you allow.
• A myStrom plug can also measure a balcony solar system: set it as balcony solar meter in Zerofy.
• With a typical Fronius home system (3–10 kW), plug loads get surplus on most sunny days; use priorities to decide whether they or bigger devices such as an EV charger come first.
• Zerofy gets new Fronius data every 5 minutes and adjusts accordingly. A minimum runtime and an activation threshold in Autopilot keep passing clouds from interrupting switching.
• Zerofy also shows your Fronius battery, so you can see whether surplus goes into the battery or into your appliances.
• If you have a plug-in balcony PV system, plug it into a WiFi Switch and set that switch as balcony solar meter in Zerofy, so its production is counted in your energy flows.

What Fronius and myStrom offer on their own

Fronius: GEN24 inverters have four digital outputs for load management (Energy Management → Load Management in the inverter’s web interface), which switch loads such as heating rods or pool pumps through an external relay when surplus is available.

myStrom: The myStrom app records mini-PV production measured by a WiFi Switch every 30 seconds, and “Solar Actions” and “Power Actions” can switch other myStrom devices on these values, e.g. allow e-bike charging from 200 W; this needs the myStrom PLUS subscription (EUR 3.49/year). Whole-house surplus control comes from energy management partners such as Solar Manager or clever-PV, not from an inverter maker.

Zerofy connects the two: it reads Fronius production and controls your myStrom switch to match, together with your other devices in one app, with dynamic tariffs and forecast-based Smart mode.

Setting up Fronius and myStrom in Zerofy

1. Connect Fronius

Zerofy reads your system from Fronius Solar.web through a guest account that you create for Zerofy.

1. Make sure your Fronius inverter is online and shows up in Solar.web.
2. In Solar.web, go to Settings → Permissions and create a new guest account.
3. Add Fronius in Zerofy and log in with the guest account credentials.

Step-by-step guide for Fronius

2. Connect myStrom

Zerofy connects to your myStrom account; it switches the plugs on and off, records their power every 5 minutes and lets Autopilot run them on solar surplus or in Smart mode.

1. Set up new myStrom plugs in the myStrom app.
2. In Zerofy, add myStrom and link your myStrom account.

Step-by-step guide for myStrom

3. Turn on Autopilot

In Zerofy, open your myStrom switch, turn on Autopilot and choose Solar – or Smart to also use dynamic tariffs and forecasts. Set the priority, activation threshold and minimum runtime.

Dynamic tariffs

Zerofy can also run your myStrom switch on dynamic electricity prices (EPEX Spot or Nord Pool, e.g. Tibber or aWATTar) or on a fixed time-of-use tariff. Smart mode combines those prices with forecasts of your household consumption and your Fronius solar production.

Learn more about Smart Mode

About Fronius and myStrom

Fronius – Austrian manufacturer of inverters, welding and battery-charging technology. Homeowners typically have a Primo GEN24 (single-phase, 3–6 kW) or Symo GEN24 (three-phase, 3–10 kW) hybrid inverter, older Primo/Symo SnapINverters, and the Fronius Reserva battery (6.3–15.8 kWh). Monitoring app: Fronius Solar.web.

myStrom – myStrom AG is a Swiss company based in Zurich, founded in 2011. Its WiFi Switch is a smart plug for up to 16 A that switches appliances and measures their power, and it is also used to measure the output of plug-in balcony PV systems. Products: myStrom WiFi Switch (CH and Schuko versions), WiFi Switch Zero, WiFi Switch Ex (outdoor, Wieland connector for mini-PV).

Manufacturer information last checked: October 2026.

All devices that work with Fronius