Jeff Geerling Suggests a Firmware Setting That Drops the Raspberry Pi 5's "Vampire" Power Draw
Drop the Raspberry Pi 5's power draw while ostensibly "off" from 1.2W to 0.01W with this one simple setting.
Developer Jeff Geerling has highlighted a little-known setting which can dramatically reduce the power draw of a supposedly-powered-off Raspberry Pi 5 — at the cost of a loss of compatibility with some Hardware Attached on Top (HAT) accessories.
"By default, the Raspberry Pi 5 (like the Pi 4 before it) leaves the SoC [System on Chip] powered up (just in a shutdown state) when you shut down the Pi," Geerling explains. "Because of this, a Pi 5 will still sit there consuming 1.2-1.6W when completely shut down, even without anything plugged in except power. That's a lot — even compared to a modern desktop PC!"
The Raspberry Pi 5 was unveiled in late September and launched last month, providing a major upgrade in performance over its predecessor — delivering anything from double to nearly 20 times the compute performance, workload-dependent. It's also the most power-hungry model, and while improvements to its loaded power draw will likely follow in future firmware updates Geerling has publicized a simple setting which can drop the device's "vampire" power draw in a soft-off state considerably.
The problem stems from a need to keep portions of the board powered up in order to support selected Hardware Attached on Top (HAT) accessories — specifically, the 3.3V power rail, which is kept live even when the Raspberry Pi is in an "off" state. If you don't have a HAT accessory known to have problems with the 3.3V rail being powered off while the 5V rail is still active, you can change the power management configuration accordingly.
Geerling advises to use the rpi-eeprom-config tool with the -e flag to edit the configuration and add the setting POWER_OFF_ON_HALT=1. When enabled and the Raspberry Pi rebooted to load the new configuration, the 3.3V rail will be powered off when the Raspberry Pi shuts down — dropping the power draw from around 1.2W to 0.01W. The change doesn't affect the power button, nor does it stop the Raspberry Pi 5's new real-time clock (RTC) from ticking away.
Geerling's full write-up on the change is available on his blog.
