Welcome to the Forum.

Is the yellow circled plug in the right hand picture plugged into something? If so, what is on the other side of the panel? If it is not plugged in to anything, that is where the power outlet would be.
If you look at the 17th diagram in this link it shows a DC/AC Inverter Module located on the right side of the front passenger's footwell. Not sure if that is what you are looking for.
2011-2015 Explorer Component Location Views
Peter