Some notes as I go along. We have
- A Renault Zoe
- A Growatt hybrid solar/battery system
- An OpenEVSE charger
- HomeAssistant instance
- An MQTT broker
The challenge is to get all of those talking together so that when the growatt battery is full and the sun is shining, any excess solar goes into the car rather than the grid.
It’s a little confusing as OpenEVSE seems to push OpenEnergyMonitor as the way to do all of this. However I don’t want yet another service on the network when I should be able to do all of this with what I have.
This looks like a good starting point.
01/02/2024
Success! It turns out the secret source is not having a leading ‘/’ on the MQTT topic of the data coming from my Growatt inverter, which is really an ESPHome ESP32 talking to Home Assistant.