MONOLITHIC PHOTOVOLTAIC SOLAR CONCENTRATOR
A photovoltaic solar collector and concentrator apparatus consists of a solid, one-piece, sun light transmitting, non-imaging optical element coupled to a photovoltaic cell. The photovoltaic solar collector and concentrator has an entry surface including focusing elements and an opposed surface including uncoated reflector elements. The focused sun light is directed by the reflector elements via total internal reflection directly towards the photovoltaic cell without any reflection from the entry surface. An additional redirecting element based on total internal reflection and integral with the collector and concentrator optical element is used to couple the sunlight from the reflector elements to a photovoltaic cell positioned in plane parallel to the entry surface.
1 . A photovoltaic solar collector and concentration apparatus comprising:
a non-imaging solar concentrator consisting of a solid, one-piece, light transmitting component having (i) an input surface including a plurality of sunlight collecting and focusing elements (ii) a stepped surface opposed to the input surface defining a series of sunlight reflectors corresponding to the focusing elements, and (iii) a concentrated light output surface; and
a photovoltaic solar cell optically coupled to the concentrator and wherein the impinging sunlight received by the focusing elements within an angle of acceptance is focused onto the light reflectors positioned to direct the focused sunlight therefrom towards the photovoltaic solar cell via total internal reflection either (a) directly and without an additional reflection from the input surface or (b) indirectly via an additional optical redirecting element.
2 . The apparatus of claim 1 , wherein the reflectors do not have a mirror coating.
3 . The apparatus of claim 1 , wherein the focusing elements are made of a material chosen from glass and plastic.
4 . The apparatus of claim 1 , wherein the optical element is made of a plastic chosen from acrylic, silicone and polycarbonate.
5 . The apparatus of claim 1 , wherein the focusing elements are spherical, aspherical, parabolic, elliptical, free form, or a combination thereof.
6 . The apparatus of claim 1 , wherein the reflectors are flat or curved, elliptical, parabolic, hyperbolic, or free form.
7 . The apparatus of claim 1 wherein the stepped surface includes a plurality of reflective steps between the reflectors.
8 . The apparatus of claim 7 , wherein the focusing elements and plurality of reflective steps form concentric rings about an axis central and normal to the concentrated light receiving region.
9 . A photovoltaic solar collector and concentration apparatus comprising:
a non-imaging solar concentrator consisting of a solid, one-piece, light transmitting component having a plurality of focusing elements coupled to a plurality of TIR reflecting surfaces;
a photovoltaic solar cell optically coupled to the concentrator to receive focused light directly from the TIR reflecting surfaces.