Originally Posted by dakini
my suspicion ... and why i asked the questions about the file ... is that the size of the file does affect battery drain. i have an 8MB epub I sideloaded, and I noticed incredibly fast drain on my battery. I've had a couple other kepubs that have been missing some of the chapter anchors and so they load large chunks -- 150 pages or so -- and they seem to drain the battery a lot faster than normal sideloaded epubs.
so, in my experience the size of the file, and how much of it gets loaded at a time, seem to affect drain, which I think is what Mrs. Often is also noticing on her device.
Thanks for passing along this information. I too find it interesting and will take it into consideration when next worrying about my battery. It seems to be working well at the moment -- 3 hours reading a day for 14 days is good enough for me.