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Why does my computer get less battery life with Ubuntu compared to Windows?
When I used Windows 7 with Dell Inspiron, I got a battery life of 2 hours. But ever since I installed Ubuntu, the battery life has taken a hit. When I recharge the battery to almost full and then unplug it from power socket, the battery shows 1:42 hours. But within a minute, this drops down to 0:41.
I even installed powertop 1.97 to combat this, but only configurations I can do in powertop is within tunables, which is shown in the figure.
I heard that powertop almost increases battery capacity by double. So, what should I do?
On some Dells the embedded controller (EC) gets confused; removing the power and the battery and leaving the machine for a few minutes for the EC to powerdown may help.
If the machine is consuming too much power it may be worth consulting: https://wiki.ubuntu.com/Kernel/PowerManagement
Have you re-calibrated the battery? This can be done by letting it drain completely, then charging it over night.
I was also experiencing this similar problem. my dell inspiron would only give 2 hours of backup. Then i found an application called jupiter. after its installation i got approx 3:30 backup power. to install jupiter just enter the following ppa in the terminal.