So I've heard on the internet that I don't have to (or even shouldn't) turn off my Mac. Instead it is suggested to put it to sleep (something about Unix running maintenance processes during night). Also a friend of mine was telling me his MBA eats about 1-2% battery during night. I've tried putting my rMBP to sleep for a few days now (basically closing lid). Power Nap is turned off, I quit all Apps before I put it to sleep. Despite all this I get about 12-14% battery drainage during 12 hours. What might be the cause? Is it normal?