kernal 2.6.21  has introduced a new feature in your linux distro called tickless . Unlike the olden days where your computer was working at a constant frequency say , 1000Hz , the processor frequency is varied to suit the requirements . A cool application named powertop had been introduced since then to take care of your power management in Linux os . Powertop is a powerful tool which assists you in identifying which hardware or software is preventing your computer from having less usage of power . Ok , now I know , you need your Ubuntu to be energy efficient right ? ok ,  install powertop .Issue the following commands to install powertop .

$ sudo apt-get install powertop

Now your computer is loaded with powertop . To see how it works , enter the following commands :

$ powertop