Maritza,
Per
FL 163.04, the Association can not deny the installation of solar panels. However, the Association "may determine the specific location where solar collectors may be installed on the roof within an orientation to the south or within 45° east or west of due south if such determination does not impair the effective operation of the solar collectors."
I suspect that the owner simply thought that since the Association couldn't deny, they didn't need to ask. Of course, that would be an incorrect thought but a common mistake. My suggestion, have the owner simply submit paperwork after the fact for documentation purposes. Run articles in your newsletter reminding everyone of the need to seek prior approval for exterior changes and move on to more important business.