Ubuntu Linux

TLP is an advanced power management tool for optimizing battery life on laptops running Linux. Its default configuration is usually enough to see an improvement in battery life, however, TLP offers a wide range of configuration options which can be changed by editing its configuration file.
 

TLP is a command line tool and it doesn't come with a graphical user interface, but there is a third-party GTK GUI (written in Python) interface for TLP, called TLPUI. For how to install and use this TLP GUI in Ubuntu, see Linux Uprising blog.