Last modified: 2021-10-15 16:36

Power Consumption

Raspberry Pis are small mobile Linux computers. So an obvious question is how long they can survive without a permanent power-supply. Here are power consumption data for different Raspberry setups. The obvious observation it that the values don't match each other very well and should be taken as what they are: one shot estimations to get an idea how long a particular configuration can run from a power bank.

Zero as desktop

For the first data series I used a Raspberry Zero WH with a button-shim soldered to it. The setup is

A Configuration Current
1 as described above 230 mA
2 no mouse 208 mA
3 no keyboard 153 mA
4 no (mouse, keyboard and) USB hub 88 mA
5 without Monitor 230 mA
6 Zero only, no devices attached 87 mA
7 one Core at 100 % 281 mA
8 with W-LAN usage 256 mA
9 with idle bluetooth 230 mA
10 with X-Windows ~ 250 mA
11 with X-Windows, 100 % CPU avg. 300 mA
12 button-shim driver running 245 mA

The descriptions in the configuration column are relative to the baseline.

Camera usage

The next table is about the camera. I used

B Configuration Current
1 idle 224 mA
2 recording video 319 mA
3 camera open but idle 319 mA

Notes:

with picamera.Picamera() as camera:
    time.sleep(30)

Raspi Zero with button-shim only

This series is about the same Raspi from A but this time only the button-shim is connected, that is

C Configuration Current
1 button-shim driver not running 80 mA
2 button-shim driver active 83 mA
3 W-LAN hotspot active 112 mA
4 scp with 2.5 MByte/sec by W-LAN 192 mA
5 powered off 38 mA

Notes:

Raspi Zero with VNC server

This scenario tests a setup, which might be more realisitic for a mobile use:

D Configuration Current
1 running, VNC server not started 79 mA
2 VNC server running but unconnected 94 mA
3 + connected to client 110 mA
4 + opened camera 185 mA

Summary

Z Option Current
1 Zero WH 80 - 90 mA
2 W-LAN without traffic +25 mA
3 Camera +100 mA
4 running as desktop 230 mA
5 Zero WH, powered off 38 mA