Q: Battery life dropped considerably on Mountain Lion.

I'm sorry to hear that so many are having problems.

For what it's worth, I have ML installed on my early 2008 17"MBP, 2010 15"MBP, 2011 11"Air and 2012 15"rMBP.  The Air and rMBP have had the SMC update.

All of these machines are getting great battery life with ML.  The 2008 MBP has a replacement battery that's about 4 months old.  I've had the rMBP since July 3rd (so it has been a month since first power on).  I've been doing mostly just coding (so typing into XCode and web browsing to look up stuff).

I charge the machine overnight, take it off charger in the morning, use it for about 2 hours before lunch time, do some browsing while I eat for about an hour, then code and reply to e-mail for another 6 hours before I go home. I generally get in another hour or so of reading my news feeds and personal e-mail at home before I get a power warning.  I almost always let it run completely down (which forces me to go to bed) before  I plug it in.

Maybe I'm lucky or just have a different usage pattern.  For reference, my 11" MBA would give me a smidgen less than 4 hours of coding usage before it needed a recharge.

Keep in mind that I ONLY use Safari as my browser, and DO NOT have Flash or Java installed.

I spend most of my time in XCode, Safari, Mail, Notes, Pulp (discontinued newsfeed reader), Pages, Keynote, iTunes and SourceTree.

Note the 10:41 below, which is a bit high...

I posted on page 2 about losing battery life after Mountain Lion install, and on another thread a couple days later saying that battery life had improved greatly after 2 days (indexing?) but was still not up to what it had been under Lion.

I got a call from an Apple engineer a couple days ago, and worked with him to get all kinds of cool info I didn't know existed to him.  They (Apple) simply could not have been nicer over the period of a few calls and emails.  Dealt with 2 different engineers, and both were extremely pleasant and, of course competent beyond the normal engineering type.

I cannot imagine having a problem with a Dell or HP and getting a call from their engineering dept. after posting on the interwebs.  Apple seems to be gathering info to get to the bottom of the battery situation.  It is odd, as not everyone is having a problem with battery life.

My machine:  MacBookPro9,1 (15" Hi-res antiglare 2012 non retina, 2.3 ghz, RAM increased to 16gb with OWC good stuff, and the 500gb Hitachi HD replaced with a Samsung 830 256gb SSD.)  The engineers both said something like "ah, same mods I'd have done on this new MBP."

They'll get to the bottom of it.

John F

LV, NV

I'll throw in as well. On a mid 2011 MBP with battery life less than half of what it was. I did discover on my own that graphics switching was turned off after the upgrade, but even then, still taking a bigger battery hit than should be expected. Just wanted to enter into the conversation in case this gets updated with any solutions. Thanks!

Perhaps I should also say that I purchased a MBA for my mother, only spec difference is that mine is an 11" and hers is a 13" screen (both mid-2011, i7, 256GB), mine usually in clamshell connected to a TBD and hers open on a kitchen table - my experience with the 11" was when took it out to a restaurant a couple of days ago) ...

Today, mom and I were doing a little lesson, via TeamViewer, and I had her leave her MBA unplugged to cycle the battery, and I was surprised at how fast her battery emptied out ... my guess, and guess only, is that we had to plug it in ca. 2.5 hours.

Other:  both have the latest Flash Player installed, and I am running Click-to-Flash on mine.  Aside from that, no exotic software except TeamViewer and VLC player on both.  Both have the SMC update installed.

Message was edited by: Robert Huebi

Same problem with a end 2011 15" MBP.

Battery life is also less than half compared with 10.7.4.

Example: charging state: 46% means battery life time of about 1 hour and 35 minutes.

And I am just reading and writing emails using mail.app.

But I have the feeling that charging takes longer also compared with 10.7.4.

So where are we now?  What is the solution? Does anyone know?    

Solution.. Chrome and find out

Solution: Don't hold your breath. Apple still hasn't solved the same problem Lion created last year

I'm starting to think the problem stems from the new version of Mail.  When I turn Mail off the batttery performance drastically improves.  Does anyone else notice this?    

No, I don't think it's mail. It could be one of the many contributors but many people are seeing battery drain with 98% "free" CPU. There are a few things than can "eat" battery, beyond CPU.

Nearly always, it points to something around the GPU. It is a known battery hog and when I last did analysis with Apple (back in December) the problems them definately seemed related.

When you look at why you need to do an SMC reset - even if it doesn't help you - it's an admission by Apple that things can go wrong and the SMC reset can do all sorts of things. I do see improved battery life (dramtically) for a while when I do a proper (it's easy to get make a mistake) SMC reset.

I think Apple will first write more debugging / performance code into the O/S to try and pinpoint when this occurs. When Apple look at my logs, unsurpsingly, they see little in the way of "runanaway" processes that can explain it. If it was "email" or any other "obvious" program, they would have found it by now. Go read the article from Apple on WHY an SMC reset is required. Even if you don't do it, it's an enlightening insigth into "things" Apple cannot catch directly! It's their own "last resort" even!

Interesting. Where is this article?  Re: GPU, I have installed gfxCardStatus, and this is not really helping either.

:-(    

Here - SMC ; http://support.apple.com/kb/HT3964

Intriguing - I wish there were more "tech" on it... I'll go look..

Familiar with this article. Another thing that makes it really difficult to nail the culprit: the reported remaining time varies considerably over the course of time, even though I have almost no applications running - just safari - and my usage does not significantly vary.  One minute I have 4 hours remaining, the next 3 hour, the next 5, etc.    

Btw - I like your screen name.     

I have Late 2011 13" i5 mbp.

I was using my mac 5-5.5 hours but now i have the same issue when i plug out the power adpt. i am seeing 98%.

CPU Temp. 64 and fan is Avg 3500 RPM this avg. is comeing with chrome (with 6 page tabs), one wallpaper app and an app which keeping copies of my cmd + c.

My bat. healt was 91% and now 83%

I done SMC resetting nothing changed...

When i open photoshop for score out my lastname for a 1 min. my cpu become 72 and fans 4300 RPM.

What can i do anything else resetting smc ?

Ps. Temp.s is Celcius