Power consumption of LEGO Bluetooth elements
Here below I have a look at battery power consumption of the following devices : Boost, Wedo 2 and Powered Up hubs, and Powered Up remote handset. During regular usage, most of the power consumption is caused by the active elements (motors), but the idle power can be significant too, especially for programmable devices that are often "on" while you are writing/debugging programs!
The battery life quoted below is the time an average alkaline battery would last at the considered current. I used a capacity of 1000mAh for the AAA cells and 2500 mAh for AA cells (WeDo 2)
Overall, thanks to the large capacity of the AA cells of WeDo 2, idle consumption is not a significant issue.
For the Boost hub, the idle current consumption is significant. Worse: if the program stops without an explicit end of program, the current remains at 145mA instead of going down to 71mA.
Powered Up Remote Handset
The power consumption in Off state is a bit high, but nothing really worrying. As a general advice, don't let batteries in any device as they might leak... For a reason I can't explain, the power consumed is lower if the hub is far away (3 - 4 meters). The paired current depends slightly on the LED color (channel), 5.2mA for green to 6.7mA for blue. Probably the LED current was adjusted to keep the same brightness...
Powered Up Hub
Idle power consumption of Powered Up hub is OK, even if AAA cells make it last less than WeDo 2 with its AA cells!