This widget only makes sense on laptops. On systems which have no battery installed, it will only report "No battery" and therefore be pretty useless. Besides, it requires that APM V1.1 be installed and working. As a rule of thumb, if the WPS "Power" object is working correctly on your laptop, the power widget should do also.
If there is a battery installed, the power widget will report two things:
Note that you can drag and drop fonts and colors onto the power widget.
You can also double-click on the widget to have the regular WPS
"Power" object opened quickly.