Raspberry Pi 3 model B power consumption
Measurements made at 5.00V with an Instek PSP-2010 programmable power supply on pins 2 and 6.
The Pi was running Arch Linux 32bit with kernel 4.4.41 idling, to figure out what was on or off, follow the sequence:
- After boot standby: 1.22W
- HDMI off: 1.18W
- hostapd on: 1.32W
- Ethernet unplugged: 1.13W
- USB off: 0.78W (wow!)
- All of the above off, downclock to 200MHz: 0.58W
- All on, 4 cores sysbench, SD write: 3.95W
The biggest lesson here is that if you don’t need USB and can use WiFi instead of Ethernet (that sits on the USB bus) you can save 0.4W which represents 33% of the idle power usage.
And if you need no network connectivity at all and no HDMI (for example you’re just controlling something via SPI) you can save as much as 0.64W (52%) by turning it all off.
For reference, these are the commands on Arch Linux:
- HDMI off: /opt/vc/bin/tvservice -o
- USB off: echo 0 > /sys/devices/platform/soc/3f980000.usb/buspower