At 0.000000001A and 2,000kV, the bell uses about 0.000002 Watts of power!,(reply>), Well alright, then!,(reply>), About 3.1 watt-hours have been spend? an iphone 6 battery has 6.91Wh and lasts claims to last 10 days on standby, so it would last 4.4624 days on this. And it's big and not rechargeable.