For those boards you need a ESP and for the Openterm device you need a special board that can handle >10V to TLL voltage.
The P1-sensor with bitbang serial communication. So you don't need external chips to invert the signal from the energy meter. This causes the communication to be less stable, however you can easily miss a message without problems.
When you do not have Home-assistant you can use this thermostat.
Connect any compatible OpenTerm CV with Home Assistant. Using MQTT
The thermal camera is connected using the esp to wifi. Goal is to make a hotspot people can join to go to the webpage to stream the realtime camera.
See blogpost
Under additional board manager URL's:
http://arduino.esp8266.com/stable/package_esp8266com_index.json
https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_dev_index.json
Under board Manage boards:
* Openterm (Ihor Melnyk)
* Adafruit_MLX90640
* Adafruit esp8266
* More I guess