Hello. Thanks to this community, I was able to get an OpenADR virtual end node written in Python to communicate with HA using MQTT. I am running HA on a Raspberry Pi 4 using HA supervised installation. The VEN is running as a separate job under Debian on the Pi. I am using the VEN to receive hourly prices from my utility. I have HA automations set up to respond to the price and control Zigbee devices connected to HA.
When the VEN receives a price event, it transmits it to HA using MQTT. I have MQTT sensors set up to make the price available to the HA automations. There are other HA automations that read energy values from devices and transmit that data back to the utility on OpenADR. The data from the devices is sent to the VEN also using MQTT.
If anyone is interested in more details I can provide a pointer to the VEN repo or answer questions about the automations, etc. It’s all pretty straightforward, and I am not an HA expert so there are probably better ways to do this than what I have done. Also this is a pilot program my utility is doing with OpenADR so it might be of limited usefulness for most people. I think it’s a good example though of how you can make HA respond to events coming from OpenADR.