I just completed a first version of a backup-script that shuts a few apps down that lock important files, starts a backup-process and waits 'till completion, then sends the computer into hibernate. I run this script now before I go to bed, this way everything gets backed up at a time when I know it doesn't bother me, yet as soon as it's done it goes into hibernate mode to save electicity.
The script is attached below. It is written using the nifty AutoHotKey software. It uses peters backup as a backup solution and Wizmo to send the computer into hibernate mode. The script is a simple textfile so adjust anything according to your needs. I left all the paths I used in the script so that you have an idea of a real-world scenario.