As much as I like the EmonTH, for me they are simply too expensive for general deployment round the house, so I have been after a cheaper alternative for a while.
I think I’ve at last found a solution.
It consists of these Xiaomi Mijia Bluetooth Hygrothermograph devices (available for around the £10 mark) with the data read using this node-red module node-red-contrib-xiaomi-ble and a PiW Zero. One advantage of these devices is they also have a display.
Whilst they are likely to not be as reliable (in reading data terms) or accurate as an EmonTH (the temperature does oscillate), they work sufficiently well to be used to manage room temperatures especially when the readings are fed through a filter.
I’m using this PiW Zero to also do some presence detection using Bluetooth and the 2 seem to sit happily alongside each other.
Of course I then publish the data through MQTT and pull it into EmonCMS