I have recently bought a very expensive new MacBook Pro with 8 GB memory and now I am frustrated by its very fast battery drainage. Often I see only 2 hours left on full battery charge!

Right now it is only 2:22 hours with no process above 200MB except 1 GB for kernel_task. Also 4 GB memory is free after a "memory clean" (I am also disappointed that Apple does not properly clean memory by itself).

What are possible causes of that low battery performance and how to deal with them?

Any help is greatly appreciated.

EDIT. I do memory clean with this app, hope it does what it says and not spreads a virus or likes.

Battery Information:

  Model Information:
  Serial Number:    D863063R190DGDLBH
  Manufacturer: SMP
  Device Name:  bq20z451
  Pack Lot Code:    0
  PCB Lot Code: 0
  Firmware Version: 406
  Hardware Revision:    2
  Cell Revision:    158
  Charge Information:
  Charge Remaining (mAh):   4976
  Fully Charged:    No
  Charging: Yes
  Full Charge Capacity (mAh):   6696
  Health Information:
  Cycle Count:  133
  Condition:    Normal
  Battery Installed:    Yes
  Amperage (mA):    2870
  Voltage (mV): 12272

UPDATE. I restarted Mac today in the morning and closed all applications - still only 3 hours. In the afternoon I have closed all applications - and miraculously I saw whopping 8 hours! Then launched Komodo and Chrome and back to 4 hours. Really puzzling...

  • What OS version?
    – bmike
    Commented Dec 15, 2013 at 4:02
  • @bmike OS 10.8.5 Commented Dec 15, 2013 at 4:26
  • Define what you mean by "memory clean"?
    – Joop
    Commented Dec 15, 2013 at 7:43
  • 5
    Know some of these apps regularly get top downloads in app Store. Follow some tech podcasts and from what i can remember consensus is that they just take your money. OSX manages memory pretty well.
    – Joop
    Commented Dec 15, 2013 at 10:58
  • 2
    Memory doesn't eat batteries, running processes do! If you open the CPU part of Activity Monitor, which are the top 5 processes and how much % of the CPU do they use?
    – nohillside
    Commented Dec 15, 2013 at 13:19

3 Answers 3


Your first step towards a solution should be to run Activity Monitor which can be found by searching in Spotlight or Applications > Utilities. Set the tab to CPU and watch for applications that are using a lot of CPU. Investigate the programs or processes that display high usage.

I recently encountered high CPU usage with Google Chrome. Web searches reveal many opinions as to the reason but the best solution is to disable Chrome plugins unless you really need them. When I disabled my plugins, the CPU usage dropped considerably.

  • I've been looking at Activity Monitors, most processes are small except kernel_task, but Chrome launches lots of them! Yet even without Chrome I see bad performance more often than not. :( Commented Dec 16, 2013 at 12:20
  • 1
    @Dmitri CPU, not memory. Memory consumption doesn't matter at all. The thing that burns all the battery is the CPU.
    – deceze
    Commented Dec 16, 2013 at 12:27
  • Mac users interested in the best battery life for their machines use Safari instead of Chrome or Firefox.
    – Bert
    Commented Dec 16, 2013 at 13:26
  • @Bert Battery whole life or time between recharge? Commented Dec 16, 2013 at 15:10

Komodo has long been known to eat a lot of CPU time (and therefore battery life) on the Mac. I'm not sure if it's because of the cross-platform toolkits they use or if the program is just inefficient. Combine this with running Chrome and you have the potential for short battery life.

Have you considered another text editor? TextWrangler, BBEdit, Coda 2, SublimeText 2, TextMate 2 are all popular options on the Mac.

  • Will look into other editors, thanks, though I've been quite happy with Komodo otherwise. Commented Dec 16, 2013 at 16:48
  • Safari seems to be slower than Chrome, though the SE seems to be hating Chrome judging by the clunky look and bugs. Commented Dec 16, 2013 at 16:54
  • Just tried Safari and "Save page" is disabled! How can I use them if they can't even let me save a page??? Commented Dec 18, 2013 at 5:54

I've just gone through two brand new MacBook Pro Retina 15's, "fresh" from Apple Store, both of which were giving me only 3-4 hours on a fresh charge.

After resetting NVRAM and SMC, I now get 5-6 or more hours.

If you buy a new MacBook -- and are getting less than 5 hours per charge -- try resetting your NVRAM and SMC.

How to Reset NVRAM:

  1. Shut down the computer.
  2. Locate the following keys on your keyboard: COMMAND , OPTION, the letter P, and the letter R.
  3. Turn on the computer
  4. Press and hold the COMMAND - OPTION - P and R keys before the gray screen appears and before you hear any chimes.
  5. Hold the keys down until the computer restarts and you hear the startup sound for the second time.
  6. Release the keys.

Reset SMC:

  1. Shut down the computer.
  2. Plug in the MagSafe power adapter to a power source, connecting it to the Mac if its not already connected.
  3. On the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time. The OPTION key is also known as ALT.
  4. Count to 5 then release all the keys and the power button at the same time.
  5. Press the power button to turn on the computer.
  6. Note: The LED on the MagSafe power adapter may change states or temporarily turn off when you reset the SMC.


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