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 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.
On several models of our laptops, Flexicharger can be used to change the top charge the computer will fill the battery to. A general consensus is that charging a battery to 100% every time will shorten it’s 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. Reduce the top charge down 10-20% to possibly gain additional battery lifespan, at the cost of daily battery life.
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. It’s 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
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.
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!
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
upower -i /org/freedesktop/UPower/devices/battery_BAT0
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.