Originally Posted by geertm
An e-ink screen only needs power to change the screen. Once the picure is on the screen the screen does not need power (even if you would remove the battery, you would still see the picure).
An e-ink screen cannot burn in, so the infrequent screen change is not a problem (the change does need power!).
Also, when I'm not going to read in, let's say, 4 hours or more I just turn off the device, sleeping mode consumes a little energy but not because the e-ink screen
but the process running on background, I think it's like 0,5% of the battery per hour.