The plugin AutomaticShutdown (https://plugins.octoprint.org/plugins/automaticshutdown/) is great if you want to turn off your Printer after your print is finished.
In my case I have the Octopi, the printer and a LED-lamp attached to a Fritz!Dect 200 remote controlled powersocket and configured it to turn itself off when the powerconsumption sinks below 12 Watts for 5 Minutes.
So if the print is finished the autoshutdown-plugin shuts down the OctoPi. The socket detects the lower powerconsumption and shuts off itself off after the specified time…
Save some energy here…