Battery life dropped considerably on Mountain Lion.

That's actually really good news [about the reinvestigation]. Please keep us updated 😟.

Yes, I have pointed their team at this thread and the other web sites / forums popping up with this "problem". If you have the issue I ask you post all the apps you know are running and any other useful concise info you have. Anything you've noticed (amazing how they all look the "same" although we know, all different). Include anything that's worked or didn't. It might show some patterns, who knows!

I upgrade my new MBPr and the battery life tanked. From 8 hours to 2 hours. I traced the issue down to Mail. With Mail shutdown all seems well. I completely rebuilt my Mail inboxes to no avail... what is the plan apple?

I've figured that Mail, Chrome, Flash is afecting battery life..

Hmmm ... Apple Mail !! Well it could be.

My computer has been running for almost 3.5 hours with MS Word, PDFs, Teamviewer a few times, dictionary. It is still showing 4.5 hrs left. This improvement could have happened because of updated Dropbox for ML and perhaps because of not running Mail.

I hope Apple is looking into it.

No such problems with Mail here, and it's trying to keep up with 5 IMAP accounts. And that's with mail "push" turned on for all of them.

You may want to try completely trashing your Mail settings an starting over from scratch. Quit Mail, then in the Finder, hold down the option key while choosing Library from the Go menu. Inside that folder, move the Mail folder to the desktop. Then look in the Preferences folder and move the com.apple.mail.plist file to the desktop.

Once you've done that, open Mail. It will be as if you're opening it for the first time. Set up your accounts again, and then let it have some time to download old mail from your IMAP accounts. Once finished, you can import any mailboxes that are missing from the Mail folder on the desktop.

If anything goes wrong with this process, move those two files from the desktop back to their original locations, replacing the newer copies that Mail has created there.

i did a completely clean install of mountain lion twice (erase and re-install) still having massive batt issues, i have no applications running in the background and i am dropping about 20% in 30 mins, of just being on safari. i finally had to downgrade back to lion.. there is definetly a bug in this software!

I agree that there seems to be an issue with Mountain Lion battery usage.

I upgraded to ML on the 26th July, and for the last 5 days everything has been running smoothly EXCEPT that my battery usage has dramatically downgraded. I am using my Macbook Pro (Early 2011) in the same manner as I was before the upgrade, running the same generic software (Mail and Safari always, plus a few other bits and pieces as needed). Prior to upgrade, I would get 6~7 hours battery life...now I am getting a maximum of 4 hours, or less...I can literally watch my battery level going down!

I am definitely not happy about this, I hope Apple comes out with a fix quickly!

Just so you know, the "design capacity" of any battery is only an estimate. If you ever try checking it every day, you'll notice that it can go up and down from day to day. Mountain Lion can definitely affect battery runtime, but it shouldn't have any effect on you battery's capacity.

I call this article a success. Apple finally got called out:

http://www.forbes.com/sites/timworstall/2012/07/31/mountain-lion-kills-battery-l ife-like-lion-did/

Hurrah .... the word is finally getting out ....

Bil 517 - Did the downgrade back to LION actually get your battery life back? This is getting curious'er and curious'er! Back in the 176 page thread of people getting this going from Snow Leopard to LION, people who went back to Snow Leopard said they got their battery life back. So;

Some who went from SL to LION had battery issues but many did not.

Some who then from LION to Mountain Lion had battery issues but many did not.

If both sets of "upgrades" and downgrades give such a mixed bag of results COMBINED with different apps seemingly effecting the battery life between the releases for different people, the fact this is SUCH a mixed bag might be an indicator of what's actually wrong. Consistent inconsistency is itself eventually a viable pattern! i.e. the variabliity of those seeing the problem is quite incredible! Lets think through what that can be. It could be a tolerance level somewhere in the O/S's, the hardware, or some application. The fact that silly tweaks like upgrading your Dropbox, reinstalling mail, PRAM resets all have some significant effect on battery life (if only for a while) is all in itself intriguing, no? I remember, back around just before Christmas when Apple helped me remove an old USB modem driver and I started seeing times of 9+ hours, I even had a real 8 hour work day (and recorded the screen shots). After about a week, something happened and I quickly got back to little more than 3 hours but we could NEVER pin point it to any one thing!

Yes, the article here is good - maybe FORBES will bring it to more senior people's attention;

http://www.forbes.com/sites/timworstall/2012/07/31/mountain-lion-kills-battery-l ife-like-lion-did/

I'm also seeing a drastic decrease in battery life on my Macbook Pro mid 2009 (2.26 GHz 8GM RAM) after upgrading from Snow Leopard to Mountain Lion.

Went from 5h-6h on a full charge to about half of that.

No Time Machine backups or indexing going on, and this happens even with everything in Activity Monitor below 10% (most of it close to 0-1%).

I'm sensing its a problem with the upgrade itself. It's not necessarily the upgrade's compatibility with the machine nor is it what it does to the machine. It could be the toll the upgrade takes on the battery [or something of that sort].

Oh well, I'm getting my rMBP today, I'll install ML and tell you the results.

I upgraded from Lion to Mountain Lion and the battery life is equals. Always 2 hours! 😟

This bug is born when i upgraded from Snow Leopard to Lion and it persist today!

I have bought a new battery but without success.

Please Apple fix it, i love you but i'm really angry for this.