Display Brightness
In order to preserve the battery you want to reduce the display brightness.
Respective Tray Icon:
Tray Icon Name  | Icon  | Where to configure  | 
Notebook BAT  | ![]()  | Menu path: Setup > System > Power Options > Battery  | 
Right-click the battery symbol in the system tray.
The context menu opens.
Click the slider of the brightness display to reduce the Display Brightness.

                                    