Educated and DD based guess on my part, but I think the UL tests are wind shear, a will they hold up on a roof at 90-110 MPH or the same on lighting standards.
Since they are eliminating the metal and glass, and fastening the Phenolic base/Epoxy top & seal Plastic panels to a roof, they likely need the UL certification for many building permit code requirments, expect say farms and ranches in the middle of no where. The Phenolic stuff is tough as nails and dates back to WWII, that stuff lasted forever.