title_body: Kindle (classic) power consumption when reading PDF vs. MOBI I'm reading mostly PDFs on my Kindle Classic (e-ink) device. Most of my e-books are PDFs, and after converting them, I've find out it's easier for me to read original PDF than converted version.
  
  However, how does the energy consumption look like? Consider the number of page changes is the same for both format, for which format the energy used to load/parse/process the energy consumption would be lower?
  
  MOBI is designed to be easier to read on e-book readers, but are those readers designed to process that format more energy-efficient than the alternatives?
upvoted_answer: If the PDF file is not formatted to the size of your Classic Kindle screen (roughly A6 format or 6"x4") you will consume a lot more power because you will need to zoom in and out and navigate on the page in order to read it. A MOBI file does not have this kind of problem because it dynamically resize the text so you can read without interaction.
  
  Your e-ink device (any Kindle generation) will be off while you read and will power on when you click on any button or on the screen. So as well as it is on sleep mode it will consume less power. The device only needs power to refresh the screen and redraw anything or change pages, thus any interaction that redraws anything consumes more power.