A supporting rack for a solar panel with a framework mountable on a surface such as a roof, this framework including two elongate runners extending parallel to each other and a cross-member extending between and connecting the two runners. Upper and lower clamp assemblies detachably and adjustably mount the solar panel on top of the framework so that the panel extends at an acute angle to the plane of the runners. There are two front clamp assemblies, each mountable on a respective runner and clamped to a front edge of the solar panel. A clevis pin connection pivotally connects the clamping mechanism to its respective runner. Two upper, rear clamp assemblies each have an adjustable J-clamp member and a back plate. After installation of the rack, the panel is pivotable from an operating position at an acute angle to the runners to a greater angle to facilitate maintenance or repair.