Power Management in Linux: How to Increase Battery Runtime

As laptops become more integrated into our everyday lives, efficient power management becomes more and more important. Not only does better power management lead to longer battery life, but conserving energy is also the environmentally conscious thing to do.

There are a few things that can be done. In addition to taking advantage of default power management settings, and perhaps installing more efficient power management software if available, there is also some power habits to consider, like the screen brightness settings or CPU usage. Here's how:

Consider your computer use. Do you leave it on when you aren't using it, instead of shutting it down or putting it in hibernate? Is the LCD screen excessively bright when dimmer settings might be more appropriate? Do you have the wireless connection on more than you actually need? Can you cut down on your CPU usage? Does the fan run more often than it actually needs to in order to keep your system cool? Does your hard drive spin up more often than it needs to? Do you keep lots of tabs open in your internet browser? Do you defragment your hard drive often?

Whew.

Believe it or not, all of these contribute to battery runtime, and they're all easy things to take into account. Simply disable functions that you use rarely, enabling them only as needed, and close out of any programs not in immediate use. Many of these can be closely monitored with the help of software programs (later in this article), but a general awareness and power consciousness is probably the best thing you can do for your power management.

Without further ado, power management programs in Linux systems:

There's no magic button on Linux to make it suddenly more efficient. Before you go and install new applications, use what you have. All distros come with some sort of power management software. This typically involves a cute little battery icon giving you the ability to adjust LCD screen brightness, hibernate/shutdown timers, and maybe a few other bells and whistles depending on the distro. Carefully go through what's available in your power management program to appropriately adjust it to your own minimum power needs.

Make sure you keep your system fully updated: some updates include power-saving features.

From here, there are two main roads to follow: frontend software programs, and BIOS and command lines utilities.

Some people want a little less terminal crunching and a little more on-the-fly usability. PowerTOP by LessWatts to the rescue! One of the most wasteful sources of CPU usage is through programs that are using it unnecessarily—programs that are idle. What PowerTOP aims to do is to identify the sources of power waste, down to the very program, and alert you to it. It's up to you from then on out to fix the issue, but PowerTOP provides a powerful starting point. Here's a program-by-program breakdown of power waste.

Using this in tandem with your default power management software, as well as general power habits common sense, will make you almost optimally efficient. However, If you want to get a bit more technical, read on. Next we will discuss which BIOS methods and command line utilities can further increase your battery runtime.