Parabolic trough solar energy collection system

Abstract

Examples and variations of apparatus and methods for concentrating solar radiations with trough solar energy collectors are disclosed. A support assembly for a trough solar energy collector has a plurality of transverse ribs attached to longitudinal rails and end assemblies secured to the rails. End assemblies may attach to longitudinal rails through transverse ribs, and guy wires may span from one of the end sections to the other. Transverse ribs may be formed of two rib sections with semi-parabolic shape. Solar energy collecting panels may be placed on the ribs and secured with cowlings and transverse panel-retaining strips, for instance.

1 . A trough solar energy collector, comprising:
 a support assembly for supporting one or more solar energy collecting panels, said support assembly further comprising:
 (a) a plurality of longitudinal rails; 
 (b) a first transverse rib and a second transverse rib both secured to said plurality of longitudinal rails, wherein each of said ribs has a shape approximating an arc of a cylindrical or parabolic surface; and 
 (c) a first end assembly and a second end assembly both secured to said plurality of longitudinal rails; 
 wherein each of said first and second transverse ribs is formed from at least two rib pieces; said rib pieces forming part of said cylindrical or parabolic surface, said first and second rib pieces having portions overlapping one another at an apex, minimum, or vertex of said cylindrical or parabolic surface; 
   at least one solar energy collecting panel; and   a collector tube positioned to receive light reflected by said collecting panel.   
     
     
         2 . A trough solar energy collector according to  claim 1 , wherein each of said rib pieces has at least a portion of its edge bent to about 90 degrees with respect to the plane of said rib piece. 
     
     
         3 . The trough collector according to  claim 1 , wherein each of said rib pieces spans at least half of said arc. 
     
     
         4 . The trough collector according to  claim 2 , wherein said rib pieces are identical or are mirror images of one another. 
     
     
         5 . The trough collector of  claim 4 , wherein each of said rib pieces has at least two mounting holes through which at least two of said longitudinal rails are inserted. 
     
     
         6 . The trough collector according to  claim 4 , wherein each said end assembly is T or Y shaped. 
     
     
         7 . The trough collector according to  claim 1  wherein each said end assembly comprises a first two identical end assembly pieces adjacent to one another. 
     
     
         8 . The trough collector according to  claim 7 , wherein said two identical end assembly pieces overlap, the overlapped portion of the two identical end assembly pieces having a first mounting hole configured to receive a first of said plurality of longitudinal rails. 
     
     
         9 . The trough collector according to  claim 8 , wherein said overlapped portion of two identical end assembly pieces have a second mounting hole configured to receive a second of said plurality of longitudinal rails. 
     
     
         10 . The trough collector according to  claim 7 , wherein each said end assembly comprises a second two identical end assembly pieces arranged identically to said first two identical pieces. 
     
     
         11 . The trough collector according to  claim 1 , wherein each of said first end assembly and second end assembly abuts one said transverse rib to triangulate each longitudinal end of said trough collector. 
     
     
         12 . The trough collector according to  claim 1  and further comprising at least one transverse panel-retaining strip to secure said solar energy collecting panel to said support assembly, wherein said strip spans all said longitudinal rails in a direction perpendicular to the longitudinal direction of the collector. 
     
     
         13 . The trough collector according to  claim 1  and further comprising at least one longitudinal panel-retaining strip to secure said solar energy collecting panel to said support assembly. 
     
     
         14 . The trough collector according to  claim 13 , wherein said longitudinal panel-retaining strip is a cowling positioned around one said longitudinal rail located at one transverse end of said trough collector. 
     
     
         15 . The trough collector according to  claim 14 , further comprising a second cowling, wherein said second cowling is disposed around said first cowling with an edge of said solar energy collecting panel positioned between said first cowling and said second cowling. 
     
     
         16 . The trough collector according to  claim 1  and further comprising a transparent thermal insulating sleeve positioned around said collector tube. 
     
     
         17 . The trough collector according to  claim 16 , wherein said sleeve has a slot along at least the majority of the longitudinal length of said sleeve and wherein said slot has a width greater than or equal to the outer diameter of said collector tube. 
     
     
         18 . The trough collector according to  claim 17 , wherein said sleeve further comprises a removable cover positioned over said slot to retain heat within said sleeve. 
     
     
         19 . The trough collector according to  claim 16  and further comprising a reflector positioned to receive light from the solar energy collecting panel and reflect the light onto the collector tube. 
     
     
         20 . The trough collector according to  claim 19 , wherein the reflector spans at least the majority of the longitudinal length of said sleeve upon a removable cover positioned over a slot in said sleeve.