Q: Battery life dropped considerably on Mountain Lion.

Disappointment.  I grew tired of my late 2010 MacBook Air's ML performance.  As mentioned earlier, half the use time and battery health diminishing quickly.  I decided to revert to Lion, the OS it came with. 

After charging it to 100% I completed a fresh, "scrape and pave" install of Lion 10.7.4.  I didn't import anything, didn't active iCloud, Dropbox, anything...just have Lion running without any open applications; screen brightness at 50% and WiFi is off.

Unplugged the mag connector and let it start indexing.  After indexing completed (about three minutes since there's not much to index) I restarted it and let the battery reading settle in.  Now after about five minutes of medium to light duty work the charge has dropped to 91% with 3:20 available.

My battery was at 95% health after 119 cycles and I averaged 6 to 7 hours of normal use (Mail, Safari, etc.) before installing ML.  Now it is 93% after 125 cycles and I'll be lucky if I get 3 hours of use.  I thought reverting to Lion would bring things back to normal.  Sadly it has not. 

Very disappointed.

I will keep an eye on it as it's possible things will improve after a couple of cycles...certainly hope so.  I'll report back if so.  But if not, since it's out of warranty I'm not sure what else to do.  My MBA was an awesome computer...one of the best I ever owned...prior to Mountain Lion.  Now it's no longer useable as a portable device IMHO.  I'm certainly glad I have an iPad to take with me...works for most things I want to do and my iMac is happy with ML, but I really miss using my MacBook Air.    Hope Apple is able to sort this out for us.

I posted some graphs (on page 113 of this mammoth thread) showing no difference between ML and Lion on my 2009 MBP.  It is very much a case of what apps and processes are running.  Your Spotlight indexing is best done with mains power and my worst case scenario was Skype video, with the iSight camera taking power too. My computer takes 0.2A while sleeping, so with 4.6Ah available, would run down in 24 hours.  I'm getting three hours under normal use, but it is quite old.

Nope, sorry, I don't buy that. If apple didn't want me to run ML because it wasn't "designed" for it, then I would not have been able to install it. While running, it runs just fine... Nice and fast and responsive. And it doesn't overheat, nor do the fans run wild... Which tells me it's not using more processor or gpu than normal.  ML didn't add any high performance doo dads that can attribute to the power loss.  Ive seen power loss with no applications running. I can't believe an OS would be "designed" to drain power as much as ML does. I stand by that there is a huge power related bug in ML.. why would there be such a huge drain even when the system is asleep? It's not doing anything, none of these new fangled HTML, flash etc.

at the genius bar, they kept telling me that apple has added over 250 new apps to this OS, and that could cause the battery to drain faster.  as for it draining while asleep, i thought i read that apple added something in this OS that kept information (like Mail, Calendar, things like that) updated while asleep.  seeing as Mail always updates when i turn my mbp on and i've lost up to 17% in one night, i doubt that's the culprit of the night drain.

I'd buy that if all 250 new apps were running at the same time! And yes, they've enhanced DarkWake which keeps power to devices and some apps even when asleep. I referenced a wwdc video that went into it. However I've pot the system to sleep after logging out...no users logged in, no apps running. And still there was power loss.

Hey jt,

Apple did not deny us installing ML- but Apple never made any performance or efficiency claims ref ML on any older systems. So the OS is not designed to drain power- it actually is designed superbly around Sandy Bridge and Ivy Bridge. It is also designed to take advantage of the amazing Intel cores and their own multithreading, tasking and so on. Throw ML on a Penryn, and if one gets 3 hours I will say they are very lucky. Same goes for 2011 units, if they were nearly as good as the Ivy Bridges,would have purchased discounted a unit.

"why would there be such a huge drain even when the system is asleep?" There is not- except on few lemon machines, and definitely, older architectures. I am receiving my replacement MBA this Tuesday and am easily betting it will have no battery problems. Current MBA, even with a wireless 2.4 Mhz mouse, I can barely exceed -800mAh drain, and I charged it every three days. Takes 90 min tops from 5% to green. Barely drains 1% overnight in sleep and apps estimate 30 days standby time. Makes sense. I believe that 99.999% of  2011 and 2012 units are not at all affected. We cannot use the minority lemons as reference to conclude that ML is such a drain. I initially thought that. But weeks of experimenting on different systems, of asking around, I could not find a single affected user in my circle of friends or Apple geniuses I know. Except here. Not bad considering the millions of Macs shipped last quarter. But easy for the few affected users all converged here and mutually reinforce a bias that ML is a hog. But  a theory is valid only if test results can be universally recreated given the same variables. This is not the case for the vast majority of mobile macbook users.

If a unit drains when at sleep, overnight, so on, I would call it defective and an oddity. Anyone disagreeing with me can just go buy a mac, test it for a week, show us, and get it reimbursed if defective.

Njersaidhi's unit is defective, and once Apple will replace it, he will come tell us how his new MBP runs very well.  And I do feel for 2011 users that appear affected and never got extra warranty, but it still appears to be a very tiny minority of affected units.

yesssss. I followed you and it seems ok. waiting until tomorrow to say for sure but so far the numbers are back to 6+ hours :-) :-)

[forget - It lasted just few minutes and then back to the previous crap numbers. The problem is still there. Apologies for the wrong information. ]

So your saying all the people here who have experienced draining while asleep... And I'm not going through 113 pages to find then.. All have "defective" units? My MacBook that has been performing flawlessly, is now defective? Sorry but I don't agree. Was ML designed specifically for new hardware? No, doubt it... Was it optimized for newer machines, sure that's why you could only install on a handful of machines. I'm sorry I dont buy that installing a updated OS makes my machine a lemon... More likely there is a problem with power handling in ML... There is a updated power management system (DarkWake).  I'm betting there is a problem with that for older machines, and some newer, than my machine being deemed a lemon because its not the latest and greatest.

jt519 wrote:

 

So your saying all the people here who have experienced draining while asleep... And I'm not going through 113 pages to find then.. All have "defective" units? My MacBook that has been performing flawlessly, is now defective? Sorry but I don't agree.

As you can't be bothered to read the post how would you know? there are enough guesses here without you adding more!

My bad, I meant I'm not going to go and reread 113 pages of posts. I've been following and reading every post, that's how I know there are others who have similar sleep power draining issues.

Sure it's only two since they've been directed to this thread, but here

https://discussions.apple.com/message/19212806#19212806

No guesses here.

jt, all I can say is the fol:

- we take your Macbook unpgraded/installed Mountain Lion.. And you have the problems you described.

- We consider 1 000 000+ macbooks with identical configuration, and Mountain Lion installed, that experience no such problems- or nothing their users could notice.

- therefore, yours is defective. It is also possible to have a working unit that stops working at some point.

- If your unit was flawless, then it would also not experience any issues. As such it is or became, at some point, underperforming and defective. With luck, it may be the battery alone- but you need to try a replacement. Even batteries have a 1/1000 failure/eratic health rate issue. A new OS, calibration and so on would merely expose it.

Overall, if your macbook drains when off or sleep, it is defective. 99.9999% of units out there do not. If they did it would be a catastrophic pr problem for Apple. Absence of evidence confirms the isolated and unfortunate situation yourself and select other users experience.

Couldn't be happier now.  A full fresh reinstall of ML did the trick for me on my Late 2011 MBP.

hi zane81, i hear you - telling you to "read the small print" is very dishonest - its dishonest because apple promotes your machine and your software as "absolutely remarkable", and apple knows as well as you and i, that there is a real problem with ML.

apple knows this because 1. people at apple can read and write, 2.these pages are on an apple website, 3.apple california dont phone people all around the world over a trifle, 4.well known and authoritative websites - just one example - just one -  Forbes (not card carrying anti apple anarchists) -  are reporting on the ML problem.. in fact everyone is reporting on the problem except apple !

as for  the lucky few who got dead machines on arrival,  the problem for the remaining 99% of us is that ML is bad for our machines, and most of us have machines out of the warranty period - how do we get new machines ?

and has anyone with a 2011 air or pro with a battery damaged by ML had apple replace the battery for free - for machines with batteries damaged by ML, but out of the warranty period...

my original post is way back - about 40 pages ago - it's hugely wrong for apple to keep selling ML without any sort of warning about problems - and at the same time tell Zane81 and me, and everyone else who speaks to apple that there is no problem with ML/its fine/wait for the next update/disable all the ML features then ML will work...

time and time again new ML users report ML problems in these pages - weeks and weeks after apple became aware of the ML problem -

downgrading back to Lion fixed my machine - but anyone reading this - remember to back up, and don't time machine everything back on to your Lion machine - if you time machine everything back - you run the risk of  bringing back the ML issues...

They replaced mine free of charge, on a 2011 MBP that is 2 months out of warranty.  I detailed my ordeal and the process I went through on here.  I had it replaced last week at an Apple Store.