Battery Life Improvements Edit on GitHub

Every running program consumes the battery. This could be a program that is part of the operating system, or a program currently in use like Firefox or Libre Office. We recommend using TLP to quickly reduce overall power consumption and using powertop to check what software is consuming the battery.

The biggest consumer of power is the display backlight. Up to 10% more battery life can be gained by reducing display brightness. Our laptops don’t currently have an ambient light sensor and brightness needs manual adjustment with Fn+F8 and Fn+F9.

Power Profiles

With the system76-power package there are Power Profiles that can be accessed in the System Menu in the image below.

FlexiCharger

On several models of our laptops, FlexiCharger can be used to change the charging behavior of the battery. A general consensus is that charging a battery to 100% every time will shorten its overall lifespan.

To adjust the top charge, reboot the computer and enter into BIOS by holding down F2, and navigate to Advanced, then Advanced Chipset Control, and set Flexicharger to Enabled. Two new sub-menus will appear, and can be set to the user’s desired percentages. The longevity of lithium batteries is dependent on the number of charge cycles they go through. The larger the percentage of spread between Top and Bottom charge percentages, the longer the physical battery will last. For optimal longevity, charge cycles of 40%~80% are a good idea:

Start Charge 40%
Stop Charge 80%

Save and exit the BIOS

• FlexiCharger will allow your System76 laptop to run solely off the AC power connection, and leave the battery alone while the computer is operating normally
• This prevents unnecessary micro-charging which reduces battery longevity
• It is particularly useful when your laptop is plugged into AC power adapter for extended periods of time
• FlexiCharger can be disabled at any time in the BIOS, which reverts the charging profile to factory defaults. Before heading out into the wild blue yonder, disable FlexiCharger to charge your laptop battery to 100%.

Useful Programs

TLP is an excellent program for increasing battery life on all of our laptops. TLP is a pure command line tool with automated background tasks and does not contain a GUI. Its default settings are excellent for most situations and require little tuning. TLP will take care of most of the settings that Powertop autotuning would, and with less trial and error.

To install TLP, run this command:

sudo apt install tlp tlp-rdw --no-install-recommends

TLP will take effect upon restart. To see current configuration settings, run this command:

sudo tlp-stat

The program is highly configurable by editing the settings file. Run this command to edit the file:

sudo gedit /etc/default/tlp

Starting with TLP 1.3 the default configuration file has changed so the command for that version is below:

sudo gedit /etc/tlp.conf

The /etc/tlp.conf file is for user configuration while /etc/tlp.d/*.conf file is for drop-in customization snippets.

All of the info about the the program can be found with these 2 commands:

man tlp
man tlp-stat

To install powertop, please open a terminal and run this command:

sudo apt install powertop

After installing the program, reboot your computer and calibrate the readings on battery power with this command:

sudo powertop -c

This will take about 15 minutes to run the calibration. The system will turn the display off a few times, and you won’t be able to do anything else on the PC during the process. Powertop can be run just by itself to see what is using resources on your system. It needs to be left open for a little amount of time to gather statistics, and be more accurate. Run it with this command:

powertop

Powertop can also generate HTML reports with this command:

sudo powertop --html=report

Open the report located at ~/report.html to see the results.

It’s useful to create a baseline by running powertop after a cold startup, without opening any applications, and then run it a few more times throughout the day to get a comparison of different workloads. Make sure to specify a different filename each time for comparison. Look at running software and see if programs can be uninstalled or if the settings of high resource using programs can be changed.

Tuning

After looking at running software, head over to the ‘Tuning’ tab. We recommend install TLP first, and then seeing if powertop finds any other tuning suggestions.

powertop provides many suggestions to increase battery life. To test enabling of all of the suggested tunings, please run this command:

sudo powertop --auto-tune

Please test the settings and make sure they doesn’t introduce any instability or oddities. The above command will only last until reboot. The most likely problem with the auto-tune command is that external USB devices have delays after inactivity. To make the new settings persist after reboot, please edit the /etc/rc.local file with this command:

sudo gedit /etc/rc.local

And add:

sudo powertop –auto-tune

above the ‘exit 0’ line, or add the individual tuning options.

Do not do this without testing! Several auto-tune settings will create system instability!

Disable Ethernet

If Ethernet is never used, or is only used irregularly, then it can be disabled to save power. Please run this command:

ifconfig

And note the name of the interface. It will probably be enp4s0f2 or similar. Disable it by running this command:

sudo gedit /etc/network/interfaces

And add this line to the file:

iface enp4s0f2 inet manual

Then, if Ethernet needs used, this command can be run to enable it for the session:

sudo ifconfig enp4s0f2 up

Useful Commands

upower -d

This will show the information that your computer can read about the battery.

sudo rm /var/lib/upower/*

If the battery life indicator is inaccurate, this will remove the stored statistics. After a few charge/discharge cycles the indicator should be more accurate.