There’s a new paper by Seyed Mahdi Darroudi, Raül Caldera-Sànchez and Carles Gomez of Department of Network Engineering, Universitat Politècnica de Catalunya/Fundació, Spain on Bluetooth Mesh Energy Consumption: A Model.
They set up some experiments to measure current consumption under various parameters:
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They found that a sensor device running on a simple 235 mAh battery, sending a data message every 10 secs, can achieve a lifetime of up to 15.6 months.
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This battery is probably a CR2032 battery. Read our post on Beacon Battery Size, Type, Capacity and Life for typical beacons battery sizes and capacities.
Read about Beacons and the Bluetooth Mesh