The beacon format is in part of the mcStudio download.
Yes beacons are extremely low power. Sending a temprature every minute get you 6 year battery life on a coin-cell.
The download contains the file BeaconWhitePaper.pdf. Beacons are send over UDP or can be sent also to MQTT. There is a .Net example in the doc, which is simple to convert to python.
We will change the web-site to make it easier to find.