A module rail for a photovoltaic system includes a module-supporting surface, and upper portion, and opposing vertical sidewalls. A first set of openings are spaced apart from one another along the length of the rail. Each of the openings in the first set extend through the upper portion for receiving a first set of fasteners for use in securing at least one photovoltaic module to the module rail. A second set of openings are spaced apart from one another along the length of the rail. Each of the openings in the second set extending through at least one of the module-supporting surface and one of the sidewalls for receiving a second set of fasteners for use in securing at least one photovoltaic module to the module rail.