Comment 31 for bug 875801

I'd like to chime in here with a few observations.

1) When gathering data from powertop one needs to ensure the sample time is long enough and also one takes a bunch of samples to ensure you are getting valid data.
2) The power consumption measurements from some batteries is tricky to estimate using tools like powertop because the battery sometimes re-calibrates the battery capacity measurements and this gives false estimations in userspace tools.
3) Twiddling all the powertop settings to GOOD settings may in fact on some hardware not actually do anything helpful, and in some cases may cause worse effects. I've measured this using a high precision multimeter and I can back this assertion with hard data.

I've got a bunch of tools in my ppa which may be useful - ppa:colin-king/powermanagement

do:

sudo add-apt-repository ppa:colin-king/powermanagement
sudo apt-get update
sudo apt-get install powerstat

and then run powerstat to see what kind of power consumption you get over a long period of time:

sudo powerstat

Powerstat will calculate average, min/max and standard deviation (the latter is useful to see how accurate+reliable your battery measurements are).

Also, I recommend taking measurements when you battery is fully charged and using this as a starting point for all your testing to ensure you are starting from a known baseline.