Sungrow SG5K-D and HomeAssistant

In December 2021 we decided to install Solar Panels on our house (thanks to Quest Energy in Perth for doing a great job), choosing JA Solar Solar Panels and a Sungrow SG5K-D inverter. Unfortunately there isn't an official Sungrow Inverter integration for HomeAssistant, but it is possible to feed solar data to HomeAssistant by sticking together a few components.

A high-level diagram showing components and data flows is given below:

 

1: SolarIoT connects periodically to Sungrow Inverter using ModBus over TCP and periodically reads the inverter's read registers and holding registers.

2: SolarIoT sends data to pvoutput.org.

3: SolarIoT sends data to a local MQTT broker on a specified topic.

4: HomeAssistant MQTT integration subscribes to the specified topic and makes the Solar Inverter data available via HomeAssistant Sensors.

This setup lets me use HomeAssistant to track my Solar production and energy consumption over the day:

Details of how to configure all the components are below:

Sungrow Inverter

I have a SG5K-D with a wifi module that sends data to iSolarCloud (and Solar Analytics) periodically. It's also possible to connect in to the wifi module and pull down data using ModBus over TCP.

SolarIoT

SolarIoT connects to a ModBus capable inverter and reads registers and then sends the data to other systems. This works well for me as I want to send my inverter data to pvoutput.org, but also want to publish the data to other local systems that will use the solar inverter data. To do the latter I've configured my instance of SolarIoT to publish the data to a local MQTT broker.

I had problems with SolarIoT with my Sungrow SG5K-D where connections would succeed most of the time, but once in a while the inverter would stop responding to ModBus handshakes. I found that I could work around this by doing a TCP connect to the inverter on the ModBus power, waiting a couple of seconds and then disconnecting and I would need to do this whenever the inverter ModBus comms went into a stuck state. I've forked the SolarIoT source here and added a feature to automate the resetting dummy connection when SolarIoT has issues communicating with the inverter (add --sungrow-reset to the command line options to use it).

I also expanded the ModBus map for the SG5K-D so it includes the "daily export energy" register which is needed for HomeAssistant's energy dashboard.

There's also a fix for pvoutput.org with the SG5K-D: the "power meter" value for the SG5K-D measures house power consumption, not the self-consumption of PV energy so this value must not be sent otherwise the data in pvoutput.org will be incorrect.

I'm running SolarIoT on one of my Linux VMs. I'll deploy it into a container eventually, I haven't gotten around to setting it up yet :)

MQTT Broker

I run a MQTT broker (Mosquitto) to manage publishing and subscribing data from various IoT sensors (e.g. Sungrow inverter, Xiaomi / Aqara Zigbee sensors, TP Link Kasa smart switches with power monitoring, OpenSprinkler and a custom battery voltage sensor I built for my powered home sliding gate). SolarIoT publishes payloads to a topic "inverter/stats".

HomeAssistant

HomeAssistant has an MQTT integration but in this case manual configuration in the config files are needed because we need to specify the device class, state class and unit of measurement fields so the energy dashboard can use the sensors. My configuration for this is below (from sensors.yaml): 

- platform: mqtt

  state_topic: "inverter/stats"

  name: "Inverter - Daily Power Yield"

  value_template: '{{ value_json["daily_power_yield"] }}'

  unit_of_measurement: Wh

  device_class: energy

  state_class: total_increasing

- platform: mqtt

  state_topic: "inverter/stats"

  name: "Inverter - Daily Export Energy"

  value_template: '{{ value_json["daily_export_energy"] }}'

  unit_of_measurement: kWh

  device_class: energy

  state_class: total_increasing

- platform: mqtt

  state_topic: "inverter/stats"

  name: "Inverter - Daily Purchased Energy"

  value_template: '{{ value_json["daily_purchased_energy"] }}'

  unit_of_measurement: kWh

  device_class: energy

  state_class: total_increasing

Just a reminder that my configuration.yaml has the following in it to read sensor config from sensors.yaml:

# manually configured sensors

sensor: !include sensors.yaml

And you also need to make sure the recorder integration has been set up to save sensor data, for example mine is below:

recorder:

  purge_keep_days: 28

  db_url: !secret URL_MariaDB

Nb. I don't have any sensors listed in my recorder section as I'm using the implicit behaviour to record all sensors.

Once the MQTT sensors have been configured and their entities are showing values from the inverter, the Energy dashboard can be set up with the MQTT sensors that we set up previously:

Once this is all set up, you'll be able to use HomeAssistant's energy dashboard (it will look like this once it has collected enough data to show a whole day's energy production and consumption):