When we get some solar, we are going portable as well. Mainly for several reasons.
First of all, I don't want to put holes in the roof. I don't want cables running all across the roof and down vents. My luck and Murphy will move in.
Secondly, many people have said about not getting optimal energy brough in with the panels laying flat. Heck, you could lay them flat on the ground for all that matters and save the holes in the roof...lol With the portable, I will be able to move them around to get optimal sun.
Lastly, I want to be able to use them at home. I plan on eventually getting a battery bank and inverter for the house. We are total electric. This would be a great option to have in case the power goes out. Plus I could operate items in the garage from time to time on it and save on my elctric bill some. I can use the protables for this.