THREE-DIMENSIONAL THERMAL OR PHOTOVOLTAIC SOLAR PANEL WITH INCORPORATED HOLOGRAPHY

The present invention relates to a solar panel with three-dimensional (3D) unitary structures or cavities that is made entirely of plastic materials and applicable to both a thermal solar panel and a photovoltaic solar module. The difference between both cases is that in the first case, the structure incorporates pipes (6) for a heat-carrying fluid, whereas in the second case it is provided with photovoltaic solar cells (8). The type of material with which they are constructed also differs: while the entire panel in both cases is still made of plastic or polymeric materials, the thermal solar application uses materials with very low thermal conductivity for retaining heat, whereas the photovoltaic application is carried out with materials with high thermal conductivity precisely for dissipating heat and preventing a decrease in cell efficiency due to heating. The assembly is very lightweight since it is made of plastic materials, and it also prevents the need for aluminum frames or external securing systems since the rigidity is assured by the structure itself, and plastic injection allows directly incorporating any securing or gripping system. It also allows adding any opening for connecting solar cells to one another. On the other hand, each 3D unitary structure concentrates sunlight on the end solar radiation receivers (pipes (6) or cells (8)), covering the entire seasonal and daily spectrum of angles of incidence, without needing active solar tracking. The thickness of said structure is quite small as a result of taking advantage of the concentrating advantages of not only one but three optical elements: on the plastic base (12) there are placed a highly reflective surface (10), a reflection hologram (9) having a wide spectral and angular bandwidth, and a transparent optical medium (11) with a refractive index and tilt angle such that it traps the light therein by total internal reflection (TIR). Optical losses are therefore significantly reduced and a large part of the solar spectrum is directed towards the radiation receiver.