$ sudo apt-get update
$ sudo apt-get install gnome-power-manager 

gnome-power-manager is installed in your system.

Make ensure the gnome-power-manager package were installed using the commands given below,

$ sudo dpkg-query -l | grep gnome-power-manager *

You will get with gnome-power-manager package name, version, architecture and description in a table

gnome-power-manager package basic information: