A bug in the power management daemon
powerd in macOS causes high CPU usage around 100-105%. On notebook Macs, this greatly impacts battery life and creates a lot of heat and fan noise.
Force-quitting the process in Activity Monitor is not affective. To kill the process, run the following command in Terminal:
pmset schedule cancelall
I recommend saving this command to a shell script and running it via
bash when needed.
#!/bin/bash pmset schedule cancelall