Growatt + SG Ready

What Zerofy can do with Growatt and SG Ready

In practice

• When there’s enough surplus, Zerofy switches the relay and the heat pump receives the SG Ready signal. How it reacts – for example by heating the hot-water tank to a higher temperature – is set in the heat pump’s own controller.
• A heat pump draws roughly 1–3 kW while running, which a typical Growatt home system (2.5–10 kW) can cover on sunny days.
• Zerofy gets new Growatt data every 5 minutes. Heat pumps shouldn’t switch often, so set a minimum runtime in Autopilot.
• Zerofy also shows your Growatt battery, so you can see whether surplus goes into the battery or into the heat pump.
• Set in the heat pump controller how many degrees the hot-water and heating setpoints rise in the boost state (“recommended operation”); the default differs by manufacturer. Fronius and Enphase only switch between normal and recommended operation, so the heat pump keeps its own minimum run times.

What Growatt and SG Ready offer on their own

Growatt: The GroBoost heater controller sends surplus solar to immersion heaters, adjustable from 0 to 10.8 kW across three outputs (three 3.6 kW single-phase heaters or one three-phase heater). Growatt’s own product pages don’t mention control of heat pumps or SG Ready.

SG Ready: Several inverter energy managers drive SG Ready directly: Fronius (GEN24 or Datamanager 2.0 with Smart Meter and a 12 V relay), SMA Sunny Home Manager 2.0 (relay or I/O module), Huawei EMMA, SolarEdge Home Load Controller or Smart Energy Relay, Sungrow SH-RT hybrids (built-in DO relay) and the Enphase IQ Energy Router+. Most of them switch on a fixed surplus threshold.

Zerofy connects the two: it reads Growatt production and controls your SG Ready heat pump to match, together with your other devices in one app, with dynamic tariffs and forecast-based Smart mode.

Setting up Growatt and SG Ready in Zerofy

1. Connect Growatt

Zerofy connects to the Growatt cloud: you log in with your ShinePhone credentials.

1. Make sure your inverter is online and registered in the ShinePhone app.
2. In Zerofy, choose Growatt and log in with your ShinePhone username and password.

Good to know: Inverter data is supported; battery and meter data may only be partly available depending on the system. Battery control and using the battery in Autopilot are listed as coming soon for Growatt.

Step-by-step guide for Growatt

2. Connect SG Ready

Zerofy switches the SG Ready inputs through a smart relay such as a Shelly that you connect to Zerofy; Autopilot then sends SG Ready signals based on solar surplus and low electricity prices.

1. Have an electrician wire a smart relay (e.g. Shelly) to the heat pump’s SG Ready inputs.
2. Add the relay to Zerofy.
3. Configure the relay as SG Ready controller in the app and turn on Autopilot.

Good to know: SG Ready gives Zerofy on/off-style states, not temperature readings or setpoints. To use all four states, the relay needs two channels, one per SG Ready input.

Step-by-step guide for SG Ready

3. Turn on Autopilot

In Zerofy, open your SG Ready heat pump, 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 SG Ready heat pump 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 Growatt solar production.

Learn more about Smart Mode

About Growatt and SG Ready

Growatt – Growatt (Shenzhen Growatt New Energy, China, founded 2011) makes string and hybrid inverters such as the MIN TL-X and MIN TL-XH series, the NEO microinverters and the NOAH 2000 balcony battery. Its own ecosystem, GroHome, adds the THOR wallboxes, APX HV batteries and the GroBoost heater controller. Monitoring app: ShinePhone.

SG Ready – SG Ready (Smart Grid Ready) is a label introduced in 2012 by the German Heat Pump Association (BWP) for heat pumps that an external controller can switch between four operating states via two contacts. It is a signalling convention, not a data protocol: the heat pump’s own controller decides how far to raise temperatures in the boost state. Products: Heat pumps with the SG Ready label (two potential-free control inputs), from many manufacturers.

Manufacturer information last checked: October 2026.

All devices that work with Growatt