The first power consumption test I did using a 6600mah (3v7 LiPo) is shown with the brown line, because I was running the LCD backlight at 100% and using a conventional laptop hard drive the power circuit called a halt when the battery was still half charged. I strongly suspect that I was simply drawing too much current for the battery to deliver as it became more depleted.
For the second test (in blue) I used a less retina burning but still quite readable 40% backlight and a solid state hard drive I managed to ride the battery all the way down to 11% with a total duration of over four and a half hours. Although I’m probably putting a bit more of a drain on the battery than I should, I can set an alarm for 30% and shutdown at 20% and still get a little over four hours battery life, not too shabby.
The (power management) reported current is shown in orange, presumably the current is on an upward slope as the battery delivers decreasing voltage…
During these test, the system was put under a low load (10%-20% single core use) grabbing a web page once every 90 seconds, the readings were take once a minute. As the usage was continuous this for me gave an automated rough equivalent of normal use by an actual user, doing browsing and office type activities – ie not 100% on all cores compiling a kernel, while running an immersive 3d first person perspective shooter!