Highly efficient solar arrays

Abstract

In an example, a solar energy system includes multiple PV modules, multiple reflectors, and a racking assembly. Each of the reflectors is positioned opposite a corresponding one of the PV modules. The racking assembly mechanically interconnects the PV modules and the reflectors to form an interconnected system. The racking assembly defines gaps within the racking assembly and between adjacent PV modules and reflectors. The interconnected system includes multiple contact points associated with the gaps. The gaps and contact points configure the interconnected system to accommodate surface unevenness of an installation surface up to a predetermined surface unevenness.

What is claimed is: 
     
         1 . A reflector configured to be implemented in a solar energy system, the reflector comprising:
 a reflective sheet configured to reflect light having wavelengths within a reflectance spectrum of the reflective sheet; and   a frame supporting the reflective sheet, the frame including two side members positioned at opposing sides of the reflective sheet;   wherein:
 each side member has a length greater than a length of the reflective sheet and is arranged such that top and bottom portions of the side member respectively extend beyond upper and lower ends of the reflective sheet; and 
 each side member includes a substantially flat upper surface extending along at least most of the length of the corresponding side member and configured to support the reflective sheet along a corresponding lengthwise edge portion of the reflective sheet. 
   
     
     
         2 . The reflector of  claim 1 , wherein:
 each side member defines a slot extending along at least most of the length of the side member and bounded at least partially by the corresponding upper surface; and   the slot of each side member is configured to receive the corresponding lengthwise edge portion of the reflective sheet.   
     
     
         3 . The reflector of  claim 1 , wherein the frame further comprises two support members extending widthwise between the two side members. 
     
     
         4 . The reflector of  claim 3 , wherein each support member includes a cross-sectional shape normal to a length of each support member, the cross-sectional shape being characterized by:
 a base member having a first end and a second end opposing the first end;   a first arc connected to the first end and a second arc connected to the second end, wherein each arc includes a first endpoint, a second endpoint and a midpoint located along the arc halfway between the two endpoints, each arc being connected to a corresponding end of the base member at the midpoint of the arc;   a leg pair connected to each arc, each leg pair including a first leg connected to the first endpoint of the corresponding arc and a second leg connected to the second endpoint of the corresponding arc; and   a foot pair connected to each leg pair, each foot pair including a first foot connected to the first leg of the corresponding leg pair and a second foot connected to the second leg of the corresponding leg pair, wherein the first foot and second foot in each foot pair are collinear.   
     
     
         5 . The reflector of  claim 4 , wherein
 each side member has a double-wall-box construction including an inner box connected lengthwise side-by-side with an outer box along at least most of the length of each side member, one side of each box being a common wall shared between the inner and outer boxes that separates the inner box from the outer box;   each arc defines a semi-circular cavity; and   the reflector further comprises a plurality of pan head screws that couple the side members to the support member, each pan head screw being assembled into the reflector such that:
 the pan head screw is inserted completely through two oversized and axially aligned holes defined in an outer wall and the common wall of the corresponding side member; 
 a threaded shaft of the pan head screw is inserted through a hole defined in an inner wall of the corresponding side member that is axially aligned with the two oversized and axially aligned holes; and 
 the threaded shaft is threaded into a corresponding semi-circular cavity of a corresponding support member until a head portion of the pan head screw rests against an inside surface of the inner wall of the corresponding side member and an end of the corresponding support member is retained against an outside surface of the inner wall of the corresponding side member. 
   
     
     
         6 . The reflector of  claim 4 , further comprising an adhesive positioned between one of the two foot pairs of the support member and a back side of the reflective sheet and configured to adhesively couple the support member to the back side of the reflective sheet. 
     
     
         7 . The reflector of  claim 1 , wherein the reflective sheet has a transmittance spectrum including particular wavelengths of visible light such that when the reflector is installed in an overhead structure provided above a particular space, natural lighting having the predetermined wavelengths illuminates the particular space after being transmitted through the reflective sheet. 
     
     
         8 . The reflector of  claim 7 , wherein the natural lighting includes wavelengths of about 400-600 nanometers for certain incident angles. 
     
     
         9 . The reflector of  claim 1 , wherein the reflective sheet comprises a glass substrate and a spectroscopic film comprising a stack of dielectric layers, the spectroscopic film being formed directly on the glass substrate by at least one of direct or reactive sputtering, chemical vapor deposition (CVD), physical vapor deposition, atomic layer deposition (ALD) or plasma-enhanced CVD (PE-CVD). 
     
     
         10 . The reflector of  claim 9 , wherein the spectroscopic film is formed directly on a top surface of the glass substrate or a bottom surface of the glass substrate. 
     
     
         11 . The reflector of  claim 10 , wherein the reflective sheet further comprises at least one of a black absorbing layer, a diffuse reflecting layer, or an aluminum layer. 
     
     
         12 . The reflector of  claim 1 , wherein the side members of the frame are formed by extrusion and include a curvature along their length to cause the reflective sheet to crown. 
     
     
         13 . The reflector of  claim 1 , wherein the reflective sheet includes a layer patterned with a laser, the patterning comprising externally visible advertising information. 
     
     
         14 . The reflector of  claim 1 , wherein the reflective sheet comprises a spectroscopic film configured to reflect light having wavelengths within the reflectance spectrum of the reflective sheet and to transmit light having wavelengths within a transmittance spectrum of the spectroscopic film, the reflective sheet further comprising a diffuse or absorbing film applied behind the spectroscopic film and configured to prevent light transmitted through the spectroscopic film from being transmitted completely through the reflective sheet. 
     
     
         15 . The reflector of  claim 1 , wherein:
 the top portion of each side member extends to a height above an upper edge of the reflective sheet when the reflector is installed in an array including a row of reflectors and an adjacent row of photovoltaic modules that face the row of reflectors; and   the top portion of each side member casts a shadow on one or more photovoltaic modules within the adjacent row of photovoltaic modules under at least some angles of incident solar illumination.   
     
     
         16 . A solar energy system, comprising:
 a photovoltaic module, wherein:
 the photovoltaic module includes a frame along a perimeter of the photovoltaic module; 
 the frame includes two side members positioned on opposing sides of the photovoltaic module; 
 each side member has a top end and a bottom end that respectively extend beyond a top edge and a bottom edge of the photovoltaic module; and 
 each side member has a single-wall-box construction; and 
   a rod received through a slot in the top end of each of the two side members, wherein the rod is coupled to a vertical installation surface and couples the photovoltaic module to the vertical installation surface.   
     
     
         17 . The solar energy system of  claim 16 , further comprising a bottom support member that extends from the vertical installation surface against a bottom portion of the photovoltaic module, wherein the bottom support member supports the photovoltaic module at an angle relative to the vertical installation surface. 
     
     
         18 . The solar energy system of  claim 16 , further comprising a base reflector that includes two protrusions on opposite ends of a common edge of the base reflector, wherein each of the two protrusions extends into a hole in the bottom end of each of the two side members to couple the base reflector to the photovoltaic module. 
     
     
         19 . The solar energy system of  claim 18 , wherein the base reflector comprises a semi-rigid layer and a reflective layer configured to reflect light having wavelengths within a reflectance spectrum of the reflective layer. 
     
     
         20 . The solar energy system of  claim 19 , wherein the semi-rigid layer comprises UV-stabilized polyethylene. 
     
     
         21 . The solar energy system of  claim 19 , wherein the base reflector further comprises a metallic stiffener that includes the two protrusions integrally formed on opposite ends thereof, and wherein a cantilever of the metallic stiffener extends into the semi-rigid layer. 
     
     
         22 . The solar energy system of  claim 18 , wherein the two protrusions define an axis of rotation of the base member and wherein the base member is configured to rotate about the axis of rotation to adjust a relative angle of the base member to the photovoltaic module.