For a very long time, there were issues regarding power and battery with the MacBook Air mid 2013 models. It was essential to fix them immediately considering its longevity.
The AppleInsider reported Apple announced the release of new MacBook Air system management controller (SMC) for its ultraportables addressing the issue that causes excessive battery drain. The MackBook Air SMC Update 2.0 targets those models of 2013 which are creating problems when the laptop lid is closed and the computer should be in a low power use mode.
There are some posts on the Apple's Support Communities forum pertaining to the battery drain problem, which also suggests that the issue is majorly related to the operating system. The post largely said the MacBook Air initially gave 10 to 14 hours of life using Chrome and Air Mail app, along with Power Point and MS Word. Once it was upgraded to Mavericks, the running battery life came down from 3.5 to 4.5 hours without adding any third party software.
The answer to this problem was specifically after a new operating system comes in, different applications sometimes do not match up with the optimization. Firefox has now version 26.0 but Chrome still needs to be upgraded with new version.
Similarly, during the previous year in October, Apple had issued MacBook Air SMC update version 1.9 addressing the issue where the battery would unexpectedly stop functioning or would it would not be recognized by the system. Apple had released a trio of SMC updates, one each for the MacBook Pro and MacBook Air Firmwares. The MacBook Pro was issued with an update 1.8, MacBook Pro Retina with 1.2 update and MacBook Air was updated with 1.9.
The current issue with MacBook Air is considered with the SMC update that requires OS X Mavericks 10.9.2 or later, or OS X Mountain Lion 10.8.5 or later to run. The update is available as a free download from the Apple Support Web site or through the Software Update app on compatible MacBook Air models. The download comes in an 804 KB.