My laptop has none of these (it also has no battery currently), but it does have a "powercap" device.
It seems this device is able to set restrictions on the user power.
And it (naturally) can read the power draw in order to enforce them.
The power draw can be found at the
energy_uj file, i.e.:
It'll show the lecture (or lectures, if you have many powercap devices) in micro-Joules.
This is actually a counter of the energy consumed, so you need to divide it by a time delta in order to get the power.
Is this the power drawn by my laptop, or just a part of it? I don't know.