Save battery power on laptops

 TLP is an advanced power management tool for Linux. It comes with a
 default configuration already optimized for battery life. At the same
 time it is highly customizable to fulfil specific user requirements.
 .
 TLP supplies separate settings profiles for AC and battery power and can
 enable or disable bluetooth, WiFi and WWAN radio devices upon system startup.
 .
 For ThinkPads it provides a unified way to configure charging thresholds and
 recalibrate the battery for all models which support it (via tp-smapi or
 acpi-call).
 .
 TLP is a pure command line tool with automated background tasks, it
 does not contain a GUI.