OS X Mountain Lion may be degrading battery life

Ars Technica carried out a number of tests showing that Apple's new operating system OS X 10.8 Mountain Lion is draining batteries significantly faster than the previous OS X Lion. The test unit lost some 38 percent of runtime after having installed Mountain Lion. The test was conducted a number of times, each using the same applications under what was described as a "daily workload." Being used actively were Safari, Chrome, Twitter, iChat, TextEdit, Photoshop, Mail and Outlook.

In a series of unscientific tests, a MacBook Pro with Retina display was run on battery power both with and without Mountain Lion installed. Ars was able to hit just over eight hours of runtime with Lion and the integrated Intel HD4000 GPU, meaning the computer wasn't leveraging the discrete and power-hungry NVIDIA GeForce GT 650M. With Mountain Lion installed and using the same settings, however, runtime dipped to around five hours.

There is no solution for the issue, but some suggested that the problem lies with one of Mountain Lion's new features like Power Nap. Another version of the problem that might cause the issue is the problem with resetting machine's system management controller. Interestingly, only certain machines are affected by the purported battery drain issue and some users are even reporting their battery life increased after installing the new operating system.