I had the same issue with Kuhno92's version guzzling the battery, so I made some modifications. I use this in my project '
Little Langtale', here's the link to the version that should be more battery efficient, inspired by Kuhno92's work for PW2 and up. I'm using a Kindle Oasis myself.
https://github.com/64bits/Little-Lan...inescreensaver