In game solar array pulls 60kw. Your 9 walls produce a total combined wattage of 45 kw by deconstructing one whole solar array to place on them. So you need 12 walls per solar panel. Maybe also add 1 metal sheet for mounting all of the panels in place, making it, 12 walls, 1 solar panel, 1 metal sheet to craft 12 walls.

I would also reduce the cost for research to remove blue science from its requirement and raise the red and green science a little. There's no need for blue science, this isn't a revolutionary concept after all. You're just gluing solar panels to a wall and with an unfortunate draw back, it requires lots and lots of power poles, or the research of substations.