You didn't post your battery stats or any info indicating it was Nova. I can tell you I've run Nova for years with no battery drain and have Nova as my default launcher on my Note 3. It is one of the best performing, least intrusive, minimal battery usage launchers you can run. It uses less battery than the stock launcher. While it's not impossible that you could have some app installed that is conflicting with it and causing trouble, with no info and no stats provided by you, I'd have to guess the problem is not with Nova just based on my own and everyone else I know that uses it experience.
There's actually not even any indication from the one screen shot you did provide that you are definitely having any problem at all. You're at 91% battery and we don't know what you were doing with your phone for those 41 minutes. I also see you have very low signal.