These quick changes increased my battery life from 5-6 hours to well over 10 hours with a Thinkpad X250. I would highly recommend these for any mobile Ubuntu install.
[raw]sudo add-apt-repository ppa:linrunner/tlp
sudo apt-get update
sudo apt-get install tlp tlp-rdw
(For thinkpads continue with)
sudo apt-get install tp-smapi-dkms acpitool
[/raw]Now update your TLP file with
[raw]gksudo gedit /etc/default/tlp[/raw]Finally Add Powertop
[raw]sudo apt-get install powertop
sudo powertop –auto-tune
sudo powertop
[/raw]Reboot
