...once you know how to open the door, get the power up & running and finding the right button to push & turn...
I don't fly the GV but on my type, you will have to do that and in less than 10 minute max or it's bye bye the battery. Of course if you know how to start the APU, all will be safe... As long as you know how to get the Gen on.
So yes, all easy when you know how
. Now as for a guy who has never seen it, putting him in the seat and asking him to do it without any kind of brief or prior knowledge, forget it.