Laptop users are concerned with getting the most out of their battery power. KDE provides a Power Management utility that makes it easy to see your current battery settings and to create power profiles that best match your needs. If you click on the battery icon in your system tray, the Power Management window will open, as seen in Figure 7.4a:
Figure 7.4a: Power Management Window of Battery Widget in the System Tray
If you don't see a battery icon, you may need to click the up arrow in the system tray to view hidden icons. If it is still not there, you can add this widget to the system tray by clicking on the Panel tool box icon (located in far right corner of the panel) -> +Add Widgets. Search for the term "battery" and double-click the battery icon. You can then click the red X to close the Add Widget window.
As seen in Figure 7.4a, this window will indicate if the battery is plugged in and the percentage of the charge. If you click the Power Profile drop down menu, you will have the option to choose from five power profiles: Performance, Powersave, Agressive Powersave, Xtreme Powersave, and Presentation. The rest of this section will show you how to view and modify the settings for each power profile.
If you wish to conserve some battery power, you can use the slider to adjust the screen brightness to the lowest usability level.
If your BIOS supports it, you can click the Sleep or Hibernate buttons whenever you wish to enter that mode.
Note: if you encounter problems with Sleep or Hibernate mode, the section on ACPI may help you to diagnose or fix the problem.
If you click the wrench icon, you will enter the Power Management utility, seen in Figure 7.4b. You can also start this utility from Kicker -> System Settings -> Power Management.
Figure 7.4b: Viewing and Creating Power Profiles Using KDE's Power Management Utility