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After searching this and other forums, I haven't seen this same issue listed anywhere for Ubuntu 12.

Prior to installing Ubuntu 12.10, my Netbook (Acer AspireOne D250, SATA HDD) was consistently getting 2:30-3 hrs battery life under Windows XP Home, SP3. However, immediately after installing Ubuntu 12.10, the battery life starts out at 2:30 hrs (99%), but less than 1 minute later suddenly drops to 1:30 hrs (99%), which seems very odd. It could be a complete coincidence that the battery is suddenly flaky at the exact same moment that Ubuntu 12.10 was installed, but that doesn't seem likely.

I'm a newbie to Ubuntu, so I don't have much experience tweaking/trouble-shooting yet. Here's what I've tried so far:

  • enabled laptop mode (sudo su, then echo 5 > /proc/sys/vm/laptop_mode) and checked that it is running when the A/C adapter is unplugged, but it doesn't seem to have made any noticeable difference in battery life,
  • installed Jupiter, but it didn't work and messed up the system, so I had to uninstall it,
  • disabled bluetooth (wifi is still on b/c it is necessary), set the screen to lowest brightness, etc.,
  • run through at least 1 full power cycle (running until the netbook shut itself off due to critical battery) and have been using it normally (sometimes plugged in, often unplugged until the battery gets very low) for a week since installing Ubuntu 12.10.
  • installed powertop, but have no idea how to interpret its results.

Here are the results of acpi -b:

  1. w/ A/C adapter: Battery 0: Full, 100%
  2. immediately after unplugging: Battery 0: Discharging, 99%, 02:30:20 remaining
  3. 1 minute after unplugging: Battery 0: Discharging, 99%, 01:37:49 remaining
  4. 2-3 minutes after unplugging: Battery 0: Discharging, 95%, 01:33:01 remaining
  5. 10 minutes after unplugging: Battery 0: Discharging, 85%, 01:13:38 remaining

Results of cat /sys/class/power_supply/BAT0/uevent:

  1. w/ A/C adapter:
    POWER_SUPPLY_NAME=BAT0
    POWER_SUPPLY_STATUS=Full
    POWER_SUPPLY_PRESENT=1
    POWER_SUPPLY_TECHNOLOGY=Li-ion
    POWER_SUPPLY_CYCLE_COUNT=0
    POWER_SUPPLY_VOLTAGE_MIN_DESIGN=10800000
    POWER_SUPPLY_VOLTAGE_NOW=12136000
    POWER_SUPPLY_CURRENT_NOW=773000
    POWER_SUPPLY_CHARGE_FULL_DESIGN=4500000
    POWER_SUPPLY_CHARGE_FULL=1956000
    POWER_SUPPLY_CHARGE_NOW=1956000
    POWER_SUPPLY_MODEL_NAME=UM08B32
    POWER_SUPPLY_MANUFACTURER=SANYO
    POWER_SUPPLY_SERIAL_NUMBER=
  2. immediately after unplugging:
    POWER_SUPPLY_NAME=BAT0
    POWER_SUPPLY_STATUS=Discharging
    POWER_SUPPLY_PRESENT=1
    POWER_SUPPLY_TECHNOLOGY=Li-ion
    POWER_SUPPLY_CYCLE_COUNT=0
    POWER_SUPPLY_VOLTAGE_MIN_DESIGN=10800000
    POWER_SUPPLY_VOLTAGE_NOW=11886000
    POWER_SUPPLY_CURRENT_NOW=773000
    POWER_SUPPLY_CHARGE_FULL_DESIGN=4500000
    POWER_SUPPLY_CHARGE_FULL=1956000
    POWER_SUPPLY_CHARGE_NOW=1937000
    POWER_SUPPLY_MODEL_NAME=UM08B32
    POWER_SUPPLY_MANUFACTURER=SANYO
    POWER_SUPPLY_SERIAL_NUMBER=
  3. 1 minute later:
    POWER_SUPPLY_NAME=BAT0
    POWER_SUPPLY_STATUS=Discharging
    POWER_SUPPLY_PRESENT=1
    POWER_SUPPLY_TECHNOLOGY=Li-ion
    POWER_SUPPLY_CYCLE_COUNT=0
    POWER_SUPPLY_VOLTAGE_MIN_DESIGN=10800000
    POWER_SUPPLY_VOLTAGE_NOW=11728000
    POWER_SUPPLY_CURRENT_NOW=1174000
    POWER_SUPPLY_CHARGE_FULL_DESIGN=4500000
    POWER_SUPPLY_CHARGE_FULL=1956000
    POWER_SUPPLY_CHARGE_NOW=1937000
    POWER_SUPPLY_MODEL_NAME=UM08B32
    POWER_SUPPLY_MANUFACTURER=SANYO
    POWER_SUPPLY_SERIAL_NUMBER=
  4. 2-3 minutes later:
    POWER_SUPPLY_NAME=BAT0
    POWER_SUPPLY_STATUS=Discharging
    POWER_SUPPLY_PRESENT=1
    POWER_SUPPLY_TECHNOLOGY=Li-ion
    POWER_SUPPLY_CYCLE_COUNT=0
    POWER_SUPPLY_VOLTAGE_MIN_DESIGN=10800000
    POWER_SUPPLY_VOLTAGE_NOW=11583000
    POWER_SUPPLY_CURRENT_NOW=1209000
    POWER_SUPPLY_CHARGE_FULL_DESIGN=4500000
    POWER_SUPPLY_CHARGE_FULL=1956000
    POWER_SUPPLY_CHARGE_NOW=1878000
    POWER_SUPPLY_MODEL_NAME=UM08B32
    POWER_SUPPLY_MANUFACTURER=SANYO
    POWER_SUPPLY_SERIAL_NUMBER=
  5. 10 minutes later:
    POWER_SUPPLY_NAME=BAT0
    POWER_SUPPLY_STATUS=Discharging
    POWER_SUPPLY_PRESENT=1
    POWER_SUPPLY_TECHNOLOGY=Li-ion
    POWER_SUPPLY_CYCLE_COUNT=0
    POWER_SUPPLY_VOLTAGE_MIN_DESIGN=10800000
    POWER_SUPPLY_VOLTAGE_NOW=11230000
    POWER_SUPPLY_CURRENT_NOW=1239000
    POWER_SUPPLY_CHARGE_FULL_DESIGN=4500000
    POWER_SUPPLY_CHARGE_FULL=1956000
    POWER_SUPPLY_CHARGE_NOW=1644000
    POWER_SUPPLY_MODEL_NAME=UM08B32
    POWER_SUPPLY_MANUFACTURER=SANYO
    POWER_SUPPLY_SERIAL_NUMBER=

Results of upower -i /org/freedesktop/UPower/devices/battery_BAT0:

  1. w/ A/C adapter:
    native-path: /sys/devices/LNXSYSTM:00/device:00/PNP0A08:00/device:02/PNP0C0A:00/power_supply/BAT0
    vendor: SANYO
    model: UM08B32
    power supply: yes
    updated: Tue Nov 27 15:24:58 2012 (823 seconds ago)
    has history: yes
    has statistics: yes
    battery
    present: yes
    rechargeable: yes
    state: fully-charged
    energy: 21.1248 Wh
    energy-empty: 0 Wh
    energy-full: 21.1248 Wh
    energy-full-design: 48.6 Wh
    energy-rate: 8.3484 W
    voltage: 12.173 V
    percentage: 100%
    capacity: 43.4667%
    technology: lithium-ion
  2. immediately after unplugging:
    native-path: /sys/devices/LNXSYSTM:00/device:00/PNP0A08:00/device:02/PNP0C0A:00/power_supply/BAT0
    vendor: SANYO
    model: UM08B32
    power supply: yes
    updated: Tue Nov 27 15:41:25 2012 (1 seconds ago)
    has history: yes
    has statistics: yes
    battery
    present: yes
    rechargeable: yes
    state: discharging
    energy: 20.9196 Wh
    energy-empty: 0 Wh
    energy-full: 21.1248 Wh
    energy-full-design: 48.6 Wh
    energy-rate: 8.3484 W
    voltage: 11.86 V
    time to empty: 2.5 hours
    percentage: 99.0286%
    capacity: 43.4667%
    technology: lithium-ion
    History (charge):
    1354023683 99.029 discharging
  3. 1 minute later:
    native-path: /sys/devices/LNXSYSTM:00/device:00/PNP0A08:00/device:02/PNP0C0A:00/power_supply/BAT0
    vendor: SANYO
    model: UM08B32
    power supply: yes
    updated: Tue Nov 27 15:42:31 2012 (17 seconds ago)
    has history: yes
    has statistics: yes
    battery
    present: yes
    rechargeable: yes
    state: discharging
    energy: 20.9196 Wh
    energy-empty: 0 Wh
    energy-full: 21.1248 Wh
    energy-full-design: 48.6 Wh
    energy-rate: 13.5432 W
    voltage: 11.753 V
    time to empty: 1.5 hours
    percentage: 99.0286%
    capacity: 43.4667%
    technology: lithium-ion
    History (charge):
    1354023683 99.029 discharging
    History (rate):
    1354023751 13.543 discharging
  4. 2-3 minutes later:
    native-path: /sys/devices/LNXSYSTM:00/device:00/PNP0A08:00/device:02/PNP0C0A:00/power_supply/BAT0
    vendor: SANYO
    model: UM08B32
    power supply: yes
    updated: Tue Nov 27 15:45:06 2012 (20 seconds ago)
    has history: yes
    has statistics: yes
    battery
    present: yes
    rechargeable: yes
    state: discharging
    energy: 20.2824 Wh
    energy-empty: 0 Wh
    energy-full: 21.1248 Wh
    energy-full-design: 48.6 Wh
    energy-rate: 13.7484 W
    voltage: 11.545 V
    time to empty: 1.5 hours
    percentage: 96.0123%
    capacity: 43.4667%
    technology: lithium-ion
    History (charge):
    1354023906 96.012 discharging
    1354023844 97.035 discharging
    History (rate):
    1354023906 13.748 discharging
    1354023875 12.992 discharging
    1354023844 13.284 discharging
  5. 10 minutes later:
    native-path: /sys/devices/LNXSYSTM:00/device:00/PNP0A08:00/device:02/PNP0C0A:00/power_supply/BAT0
    vendor: SANYO
    model: UM08B32
    power supply: yes
    updated: Tue Nov 27 15:54:24 2012 (28 seconds ago)
    has history: yes
    has statistics: yes
    battery
    present: yes
    rechargeable: yes
    state: discharging
    energy: 18.1764 Wh
    energy-empty: 0 Wh
    energy-full: 21.1248 Wh
    energy-full-design: 48.6 Wh
    energy-rate: 13.2948 W
    voltage: 11.268 V
    time to empty: 1.4 hours
    percentage: 86.0429%
    capacity: 43.4667%
    technology: lithium-ion
    History (charge):
    1354024433 86.043 discharging
    History (rate):
    1354024464 13.295 discharging
    1354024433 13.662 discharging
    1354024402 13.781 discharging

I noticed that between #2 and #3 (0 and 1 minutes after unplugging), while the battery still reports 99% charge and drops from 2:30 hr to 1:30 hr, the energy usage goes from 8.34 W to 13.54 W and the current_now increases, but shouldn't it be using less energy in battery mode since the screen is much dimmer and it's in power saving mode? (or is that normal behavior?)

It also seems to drain more quickly than what it predicts, especially with the 1-1.25 hour drop in the first minute of being unplugged, which seems odd.

What really concerns me is that Ubuntu 12.10 may not be properly managing the battery (with the sudden change in charge/life from 2:30 to 1:30 or 1:15 within a minute of unplugging), and that a new battery may quickly die under Ubuntu 12.10.

I'd greatly appreciate any advice/suggestions on what to do, and especially whether there's a way to get back the 1-1.5 hrs of battery life that were suddenly lost when changing from WinXp to Ubuntu 12.10.

Thanks :)

share|improve this question
    
Not so much an "answer" per se, but you have to run powertop in the terminal. so sudo powertop then while its running it should give you options to press specific keys to enable / disable certain functions. Also, You could try uninstalling any and every program you're not actually using. In my experience some programs will run background processes and it seems to me that this absorbs more cpu time and therefore more power. Best of luck I'll be curious to see the "solutions". –  Arammil Jan 23 '13 at 16:44

2 Answers 2

Your battery is shot and needs replaced:

energy-full: 21.1248 Wh
energy-full-design: 48.6 Wh
capacity: 43.4667%

This shows the battery is holding less than half of its design capacity.

voltage: 12.173 V

This is also off; the fully charged voltage should be 12.5 V.

share|improve this answer
1  
I wouldn't say that it needs to be replaced but it should if you want full capacity again. –  André Stannek Nov 27 '12 at 17:04

Basically the answer of @psusi is right but I might have a workaround.

The fact that Windows runs longer on that battery indicates that it has still more capacity than Ubuntu calculated. If this is the case, it can run longer than the shown battery time. All you have to do is to disable the automatic shutdown on low power as explained in this answer.

If you do so your laptop will keep running even though Ubuntu shows 0% battery power. The only problem is you have no way to tell how long. At some point, it will turn of without a warning. Besides from not being properly shut down, you will loose unsaved data.

share|improve this answer
1  
The capacity is measured by the battery itself, not Ubuntu. The windows getting longer runtime is probably just remembered from when the battery was in better condition. –  psusi Nov 27 '12 at 19:54
    
Of course, thanks for pointing that out. Corrected my answer. –  André Stannek Nov 27 '12 at 21:26
    
Thanks for the info, but I don't need the battery to have full capacity. I just need it to have the same or similar capacity that it had under Windows XP (a few minutes before I installed Ubuntu 12.10 and immediately lost 1 hour from the battery life). So, psusi, 2.5 hrs isn't "remembered" from when the battery was in better condition. Windows still has 2.5 hrs battery life and Ubuntu isn't utilizing this 2.5 hr capacity). So, the question remains - why Ubuntu 12.10 has 1 hour less battery time than Windows XP Pro does, and what to do about it? Thanks! :) –  zondu Jan 22 '13 at 19:00

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