Solar panel roof

A solar panel system mounted on a roof of a building, comprising:

• a plurality of supporting joists arranged substantially normal to an upper ridge of the roof, and extending from said upper ridge to a lower region of the roof, and
• a set of rectangular solar panels, each solar panel supported along opposing sides by two said supporting joists,
• wherein each respective joist is formed with a plurality of wedge-shaped recesses, each recess having, in an end closest to the upper ridge, an end surface normal to the roof extending across a width of the respective joist, and a flat, sloping supporting surface meeting with a bottom edge of the end surface, said plurality of recesses together forming a saw-tooth contour, said end surface having a height substantially corresponding to a thickness of said solar panels, wherein each solar panel is received in respective wedge-shaped recesses of respective supporting joists, resting on respective supporting surfaces of said respective recesses with an upper edge of each solar panel meeting respective end surfaces of said respective recesses, and wherein an upper said solar panel has a lower edge which protrudes over an upper edge of a lower said solar panel in an overlapping manner,
• further comprising a set of fixation elements configured to fix the solar panels to the supporting joists, each fixation element having a saw-tooth contour matching the overlapping solar panels.