I just recently upgraded from lion to mountain lion on my 13 inch macbook air 2011 and i realized a significant drop in battery life. When i was on lion, my average battery life was around 5 hours but now with mountain lion it significantly decreased to 2 1/2 - 3 hours (Doing the same tasks and on the same brightness). Anyone experiencing the same issue and any solutions that i could try? If nothing else works i might just bring it to the genius to have it check upon. I've looked at GGJStudio's battery life guide: http://forums.macrumors.com/showpost.php?p=9875442&postcount=23 but it didn't help. My battery health : 87% and with 237 charges. Looked up activity monitor and realized kernel_task taking up about > 15% cpu and using up 300 mb of ram Thanks!