Fronius + go-e

What Zerofy can do with Fronius and go-e

In practice

• Zerofy can switch your go-e Charger between one and three phases. Solar charging can therefore start at about 1.4 kW of surplus (6 A on one phase) and move to three phases once the surplus passes about 4.1 kW.
• A typical Fronius home system (3–10 kW) reaches the 1.4 kW single-phase minimum on most bright days; three-phase charging from about 4.1 kW needs a sunny midday or a larger system.
• 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 charging.
• Zerofy also shows your Fronius battery, so you can see whether surplus goes into the battery or into the car.
• If your car is connected to Zerofy too, turn on Autopilot for either the car or the charger, not both.
• The go-eCharger charges from 6 A, about 1.4 kW on one phase and 4.1 kW on three. Zerofy charges single-phase up to about 3.7 kW of surplus and switches to three phases above that; go-e lists automatic phase switching for Gemini models and HOME V3, so older HOME units stay on the phases they are wired with.

What Fronius and go-e offer on their own

Fronius: Fronius sells its own Wattpilot wallboxes, manufactured by go-e in Austria, a company Fronius holds a stake in. Wattpilot charges on solar surplus from 1.38 kW with automatic 1/3-phase switching, but only with a compatible Fronius inverter (GEN24, Verto, SnapINverter with Datamanager 2.0) and a Fronius Smart Meter at the grid connection point.

go-e: go-e’s own route to surplus charging is the go-e Controller, which measures the house connection with six current sensors and works with any inverter brand, including automatic 1/3-phase switching. Without the Controller, go-e relies on external energy managers through its open API, Modbus TCP or OCPP.

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

Setting up Fronius and go-e 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 go-e

Zerofy uses the go-e Cloud HTTP API with your charger’s serial number and API token, sets the charging current and switches between one and three phases.

1. Update the charger to firmware 052 or later and the go-e app to 2.3 or later.
2. In the go-e app, go to Internet → Advanced Settings and turn on the Cloud HTTP API.
3. Copy the API token shown there and enter it in Zerofy together with the charger’s serial number.

Good to know: Supported are Gemini 2.0 (serial 400000+), Gemini (200000–399999) and HOME (050000–199999).

Step-by-step guide for go-e

3. Turn on Autopilot

In Zerofy, open your go-e Charger, 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 go-e Charger 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 go-e

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.

go-e – go-e is an Austrian charger maker. The current go-eCharger Gemini 2.0 (11 or 22 kW) has documented local and cloud APIs, MQTT, Modbus TCP, a freely configurable OCPP backend and an eSIM; according to the data sheet it is not approved for the Netherlands, France or Italy. Products: go-eCharger Gemini 2.0, Gemini, HOME.

Manufacturer information last checked: October 2026.

All devices that work with Fronius