Energy saver feature is divided into several different options to prolong a computer's battery life by optimizing a resources consumption.
All of the following features are usable only when the computer's charger is unplugged and it's running from battery.
Parallels Toolbox for Mac
Hide non-active apps
When you enable this option Energy Saver hides active (idle) applications.
It makes the hidden applications go to Mac's built-in App Nap mode in which they consume very little energy.
Pause non-essential processes
With this option enabled Energy Saver pauses a number of system processes which are always running in the background.
These processes include Spotlight indexing, AppStore updates check and macOS updates check.
Having these processes paused significantly extend battery life.
Eject external devices
When this option is selected Energy Saver tries to eject all external devices which are connected to the Mac at the moment.
It includes hard disks and smartphones.
NOTE: Energy Saver may fail to eject the drives if they are in use (e.g. the data is being transferred to/from the drive or it's being formatted).
Pause Time Machines backups
After choosing this option Energy Saver temporarily prevents Time Machine from creating regular backups.
Since Time Machine backup process mostly consumes a lot of Mac resources, having this option set drastically reduces overall energy consumption.
NOTE: Energy Saver does not stop Time Machine backups if they are already in progress.
Important: make sure not to have this option to be always on if Time Machine backups are critical to you.
Parallels Toolbox for Windows
Launch when on battery
When you enable this option Energy Saver activates once you unplug the PC from a charger.
Windows Power Plan settings are modified by enabling the following options.
Reduce screen brightness
After choosing this option Energy Saver automatically reduces screen brightness based the amount of battery charge left.
Enable CPU optimizations
With this option enabled Energy Saver limits CPU peaks preventing the computer from excessive resources consumption and overheat.
Enable video optimizations
When this option is selected the computer's video card is set to the fastest response, therefore video quality is reduced and Windows Aero affects are disabled for a longer battery life.
Enable other optimizations
When you enable this option Windows power saving settings are mostly affected.
The computer screen and the connected external hard drives and external displays will be automatically ejected/disconnected when the computer is left idle for longer than a minute.