Test results, published by Appleinsider, show a significant improvement in battery life in MacBooks as a result of installing the new OS X Mountain Lion 10.8.2 beta developer build. Using the latest beta version of OS X, MacBook battery life has increased by 85 minutes compared to the current version 10.8.1.
The Mac Observer benchmarked multiple OS X versions for comparison, from Snow Leopard 10.6 to Mountain Lion 10.8.2 (developer build 12C35). The impact of the operating system on battery life was determined.
For testing, we used a 2011 15-inch MacBook Pro based on an i7 processor with a frequency of 2 GHz, and 8 GB of RAM, a Radeon HD 6490M graphics card, two internal hard drives: an OCZ Vertex 4 64 GB SSD and a Seagate Momentus 750 GB HDD.
Each operating system was tested with a full battery, all applications and services were disabled, including Wi-Fi. The screen brightness was set to 50 percent, the display was set for long-term active use, the screensaver was disabled. Automator simulated typical medium power workflows and repeated them until the battery was completely depleted.
Taking Mac OS X 10.6.8 Snow Leopard as a starting point, the final benchmark results showed significant improvements in battery life with the release of OS X Lion Mountain 10.7 and 10.8. In subsequent versions, the battery life dropped by more than 40 minutes, and only after the release of three more versions was it restored to the original level of Snow Leopard. The Mountain Lion, released in July, is especially striking: a huge loss in battery life of a whopping 105 minutes. With the release of the latest version 10.8.1, this figure dropped by 30 minutes.
However, with the release of OS X 10.8.2, battery life was not only restored to Snow Leopard levels, it was breaking records. OS X 10.8.2 outperforms all of its predecessors, delivering 8 minutes more work over Snow Leopard and 88.5 more minutes over the previous version, Mountain Lion 10.8.1.
Earlier it was reported that with Mountain Lion, users experienced multiple issues related to battery life. In particular, some MacBook Air owners have argued that after installing Mountain Lion OS X 10.7, the battery lasts barely half the time it did before. Subsequent tests of the latest official release, Mountain Lion OS X 10.8.1, showed that Apple engineers worked hard on the battery life issue, resulting in a significant increase in battery life.
These tests prove that the latest OS X 10.8.2 beta developer release will provide even longer battery life, perhaps even outperforming its predecessor OS X 10.6 Snow Leopard.
So far, the official released version of OS X 10.8.1 cannot boast of the presented successes in power saving, demonstrated by the aforementioned testing. In the meantime, Apple is determined to work further on the issue of increasing battery life after the release of Mountain Lion.
