After numerous reports of poor battery performance under OS X Mountain Lion, ArsTechnica performed tests that confirmed a 38% reduction in battery life.
Our own testing revealed similar (and significant) drops in battery runtime after installing Mountain Lion. In previous tests, we were able to regularly achieve just over 8 hours of use by relying solely on our Retina MacBook Pro's integrated Intel HD4000 GPU. Performing the same "real-world" test using the same software applications and usage pattern, we never got the Retina MacBook Pro to run for more than a few minutes past 5 hours after a full charge.
Steve_c, a user contacted by Apple Support about the issue, confirmed it was software based. "I can confirm this is definitely a software (OS) issue, as the guy that was dealing with me said that an update will be issued via the [Mac App Store] as soon as they can work a fix."
Apple hasn't officially confirmed a fix is coming but the site did forward all their test results to the company for analysis.
Let us know if you've experienced an issue with battery life after installing OS X Mountain Lion in the comments.
Yup.. I figured there were poor battery issues on my 17" MBP (early 2011 ver) but I thought it was my imagination.. hope Apple provides an update soon!! It's just about bearable for now..
Noticed significant battery decrease on Macbook Retina display since Mountain Lion update, even with notifications all turned off.
Hope they sort it out soon!
it was on sleep since yesterday, i did some tasks including connecting a superdrive for viewing some photos, now i'm using it just for surfing the net, and actually updating the Xcode, light is dimmed to half, key lights half as well,
the percentage is now: 76% and 5.24 hrs remaining.
i didn't notice that it is loosing power fast,
I have an aluminum MacBook (not a pro) that was produced for a short time and I saw a significant decrease in battery on lion and standby times that were about a day on a full charge. With mountain lion my battery life has increased to over 2 hours again and standby time has increased greatly, maybe only loosing 5% in a day now.
Perhapse I just had a bad install but mountain lion has done wonders for my little old MacBook.