OS X 10.8.2 Restores Notebook Battery Life to OS X Lion Levels

Just over a month ago, Ars Technica reported that many users had noticed a significant decrease in battery life on their notebooks after upgrading from OS X Lion to OS X Mountain Lion. In its own testing, Ars Technica saw a 38% decrease in battery life following the upgrade.

The Mac Observer followed up with more extensive testing showing a similar 33% drop in battery life on a test machine following the upgrade to OS X Mountain Lion, and also finding that OS X 10.8.1 improved battery life over the original Mountain Lion release. The improvements did not, however, bring battery life back up to the levels seen under OS X Lion.

With OS X 10.8.2 now well into testing, The Mac Observer has performed its most complete set of tests yet, not only testing the effect of moving from OS X 10.8.1 to Build 12C35 of OS X 10.8.2 on battery life, but also looking at upgrades from OS X Snow Leopard to OS X Lion.

Of most immediate impact, The Mac Observer's study shows that the testing build of OS X 10.8.2 completely restores battery life to OS X Lion levels, yielding approximately 380 minutes of power under the testing protocol, compared to 260-275 minutes under OS 10.8.0 and 280-300 minutes under OS X 10.8.1.

Just as we saw in our previous tests, the upgrade to 10.8 Mountain Lion decreased battery life significantly, by about 1 hour and 45 minutes, or 30 percent. The upgrade to 10.8.1 restored about 30 minutes of battery life for our MacBook Pro, an improvement for sure, but not nearly enough to regain lost ground.

The big change came with 10.8.2, which is still undergoing developer testing. Using the latest build, 12C35, we saw a tremendous increase in battery life, to the point where running time was a few minutes longer than even that of 10.6.8.

10 8 2 battery life
In addition, the study shows that users experienced a similar but smaller effect on battery life with the introduction of OS X Lion, an issue that was not fully resolved until the release of OS X 10.7.3 over six months after the public debut of OS X Lion.

Not all notebook users have experienced significant battery life reductions under OS X Mountain Lion, and thus it is unclear exactly what the root cause of the issue is. But for those who have been suffering from the problem, it seems that OS X 10.8.2 may deliver a resolution that will restore full battery life to their machines.

Top Rated Comments

D.T. Avatar
109 months ago
Lost my power adapter, running on battery right now, hope this comes out in the next 2 hours and 38 minutes ...
Score: 86 Votes (Like | Disagree)
edk99 Avatar
109 months ago
Am I reading this right that a SSD has a shorter battery life then a HDD? I would of thought something with moving parts used more power then something that has no moving parts. :confused:
Score: 41 Votes (Like | Disagree)
tanousjm Avatar
109 months ago

Maybe I'm missing something here, but aren't SSDs supposed to increase battery life compared to HDDs?

And I'm not talking about the ~5 minutes differences here, from what I've read SSDs were supposed to significantly increase battery life.


Hi guys; I performed the tests for The Mac Observer. As I explained in the article, we were also confused as to why the HDD was getting better battery life than the SSD. We looked into it and discovered that our hard drive, a Western Digital Scorpio Blue, is extremely power efficient, using .59 watts at idle and 1.4 watts while active.

This is very low for a mechanical hard drive and our high performance Vertex SSD used more power: 1.3 watts idle, 2.5 watts active.

Some low speed, energy efficient HDDs have closed the gap in power consumption with SSDs, but YMMV.
Score: 25 Votes (Like | Disagree)
Xenomorph Avatar
109 months ago
But is Safari snappier?
Score: 20 Votes (Like | Disagree)
AngerDanger Avatar
109 months ago
Introducing the all new, previous battery life. Only on Mountain Lion :apple:
Score: 15 Votes (Like | Disagree)
charleswhalley Avatar
109 months ago
OS X 10.8.2 Restores Notebook Battery Life to OS X Lion Levels

Apple are you listening. Far too many products - hardware and software are being released that clearly need months more development testing. You mojo will be lost sooner rather than later if this continues.

I wonder what the iPhone 5 has wrong with it......
Score: 14 Votes (Like | Disagree)

Top Stories

lg wing

LG Considering Exit From Smartphone Business, Halts LCD Production for iPhone

Wednesday January 20, 2021 5:38 am PST by
LG is considering exiting the smartphone business entirely amid declining shipments and accrued losses of $4.5 billion over the past five years (via The Korea Herald). LG CEO Kwon Bong-Seok cautioned staff earlier today that the company is re-evaluating its presence in the smartphone industry: Since the competition in the global market for mobile devices is getting fiercer, it is about...
google maps detailed street level e1611052089473

Google Maps Gains Enhanced Street-Level Detail in Four Major Cities

Tuesday January 19, 2021 2:34 am PST by
Google Maps has quietly been updated to include significantly more detailed street-level information in a handful of key cities around the world. Upon zooming in, Google's maps for Central London, Tokyo, San Francisco, and New York now benefit from shapes and widths that match the scale of roads more accurately. Meanwhile, enhanced graphical representations of sidewalks, crosswalks,...
2019 mac pro side and front

Tim Cook Gifted Donald Trump 'First' 2019 Mac Pro

Wednesday January 20, 2021 5:45 pm PST by
Apple CEO Tim Cook gifted former United States President Donald Trump with the first 2019 Mac Pro that came off of the assembly line in Austin, Texas, according to a financial disclosure report that was released today (via The Verge). "Mac Pro Computer, the first created at the Flex Factory in Austin, Texas," reads the entry, which values the machine at $5,999, the base price for a Mac Pro....
airpods max sim ejector

AirPods Max Headband Removable With Just a SIM Ejector Tool, Hinting at Interchangeable Headbands

Tuesday January 19, 2021 8:25 am PST by
It is possible to remove the headband of AirPods Max with just a standard SIM card ejector tool, hinting at the possibility of interchanging headbands to achieve a different colorway. Image via Prelook In December, MacRumors revealed the large variety of AirPods Max ear cushion color combinations when it became clear that they were magnetically attatched and available for sale separately....
iphone 5s black slate

Images of Unreleased iPhone 5s in Black and Slate Shared Online

Sunday January 17, 2021 9:47 am PST by
Twitter user @DongleBookPro has today shared images of a prototype iPhone 5s in an unreleased Black and Slate color. The iPhone 5s was launched in September 2013. The device featured Touch ID, a 64-bit processor, and a True Tone LED flash for the first time. Other new features included a five-element lens with an f/2.2 aperture, a 15 percent larger camera sensor, Burst Mode, and Slo-Mo...
iphone 12 vs iphone 12 mini

Apple Shifting Some Production From iPhone 12 mini to iPhone 12 Pro to Meet Demand

Wednesday January 20, 2021 8:12 am PST by
Apple has reportedly cut production of the iPhone 12 mini by two million units to create more manufacturing capacity for the iPhone 12 Pro, according to a new Morgan Stanley investment note seen by PED30. Apple is believed to have made the switch for the first quarter of 2021 in an effort to combat continuing lead times for the more popular iPhone 12 Pro. iPhone 12 Pro lead times remain ...
Apple VR Feature

Bloomberg: Apple's First AR/VR Headset 'Pricey, Niche Precursor' to More Ambitious AR Glasses and Could Launch Next Year

Thursday January 21, 2021 3:27 am PST by
Apple's first virtual reality headset will be a "pricey, niche precursor" to a more ambitious augmented reality product, according to a new report from Bloomberg's Mark Gurman. As a mostly virtual reality device, it will display an all-encompassing 3-D digital environment for gaming, watching video and communicating. AR functionality, the ability to overlay images and information over a view...
shot on iphone 12 apple

Apple Highlights Photos Shot by iPhone 12 Users: Portraits, Cityscapes, and More

Tuesday January 19, 2021 6:05 am PST by
Apple today shared a gallery of photos shot by customers using the iPhone 12 mini, iPhone 12, iPhone 12 Pro, and iPhone 12 Pro Max, with scenes including cityscapes, landscapes, portraits of people, and more at day and night. Shot on iPhone 12 Pro Max by "NKCHU" in China (top) and shot on iPhone 12 Pro Max by Rohit Vohra in India (bottom) iPhone 12 mini and iPhone 12 models have a dual camera ...
Apple and Hyundai feature

Apple Car Production Again Linked to Kia Motor's US Plant in Georgia

Tuesday January 19, 2021 4:19 am PST by
Hyundai intends to transition the company's Apple Car involvement to its Kia brand as part of an internal arrangement that could see production move to the U.S., according to a new report today. On Sunday, Korea IT News reported that Apple and Hyundai are seeking a partnership agreement for the upcoming Apple Car by March, and that the electric vehicles could be made at a Georgia factory...
iPhone 13 Notch Feature

iPhone 13 Rumored to Feature Smaller Notch, Pro Model Cameras to Use Larger Image Sensor

Thursday January 21, 2021 1:38 am PST by
Apple's iPhone 13 series will feature a redesigned Face ID system that will allow for a smaller notch at the top of the screen, according to a new report today. The rumor comes via hit-and-miss Taiwanese industry publication DigiTimes, whose supply chain sources also claim that the ultra wide-angle lens in Apple's next-generation iPhones is due for an upgrade. The next-generation iPhones'...