I'm looking at whether to buy a wireless electricity monitor such as this:
<(Amazon.com product link shortened) />/ B000LQ79Q6/ref=sr_1_1?ie=UTF8&s=electronics&qid02911664&sr=1-1>
which clips around the input meter lead so measuring the current and multiplies this by a set voltage to calculte the power consumption.
Or to buy a power monitor that actually measure the power used by the device:
<(Amazon.com product link shortened) />/ B000Q7PJGW/ref=pd_bxgy_ce_img_b?ie=UTF8&qid02911664&sr=1-1>