NOVELTY - The assembly (1) has a support frame (2) for supporting a photovoltaic panel (5), where sides (2A-2D) of the frame are made from a single and same hollow section and assembled in a water-tight manner. The section comprises a lower face, two side faces and an upper part that carries a gripping unit to hold an edge of the panel, where the section is made of plastic i.e. PVC. Internal vertical and horizontal partitions extend from one of the side faces to the other side face and/or from the upper part to the lower face of the section to form compartments in a core of the section.    USE - Photovoltaic panel assembly for use in a photovoltaic power plant (claimed) that is arranged on a roof of a building, a land and at a high corrosion environment such as sea or aquatic corrosion environment e.g. water treatment, industrial or closed basin, for producing electricity.    ADVANTAGE - The section is hollow and made of plastic, so that the sides of the frame made from the section are insensitive to corrosion, and the frame exhibits buoyancy, thus enabling installation of the photovoltaic power plant at the high corrosion environment. The design of the assembly enables providing lifting elements on the frame to adjust the inclination of the panel according to an installation location of the panel such that the panel forms an angle, which is less than or equal to 15 degree, with a median plane of the frame, thus allowing cleaning of the panel by streaming so as to reduce maintenance cost of the assembly and increase service life of the assembly, and enabling the surface of the panel turned toward the Sun to be orthogonal to the Sun rays, irrespective of inclination of a surface on which the frame is installed, so as to increase the electricity production efficiency of the panel, while avoiding shadow between the panel and an adjacent panel. The assembly is simple in design.    DESCRIPTION OF DRAWING(S) - The drawing shows a perspective view of a photovoltaic panel assembly.    Photovoltaic panel assembly (1)    Support frame (2)    Sides of support frame (2A-2D)    Photovoltaic panel (5)    Grooves (11A-11C)