I don't have it here at the house, and I cannot recall the name of it, but I have a device that you connect in line (in the power cord) to a device, and it records the energy consumption. (We used it to decide whether to replace an old style freezer.)
Laser printers DO use a good deal more power than inkjets, unless that has changed. It used to be that many of my (Amish) customers were running off of a small generator (Honda 2000, for example) to charge a battery, or small solar arrays. A laser printer would bring everything down as soon as you turned it on - had to have a generator running. (This was around 10 years ago.)