Cyanogen OS 12 was recently announced with Android Lollipop. While it has great features, some users have reported a huge battery drain. The root cause of this drain has been found out and it is believed to be OTA update component of Google Play Services (SystemUpdateService), which was disabled in KitKat and earlier versions of Cyanogen.
XDA developers have identified this issue and have created a fix for it. They have made a modded Google Play Services package that can help solve the battery drain problem. Follow the guide below to fix this issue.