Double reflecting solar concentrator

Abstract

A double reflecting solar concentrator utilizing a primary reflective surface which reflects incident light toward a secondary surface. The incident light reflects off the secondary surface away from the primary surface's natural focus point toward a secondary focal point positioned on or substantially near the surface of the primary reflective surface.

What is claimed is:  
     
         1 . A solar concentrator comprising: 
 a substantially planar primary reflective surface; and    a secondary reflective surface having a substantially parabolic curvature, the secondary reflective surface positioned adjacent to the primary reflective surface such that at least a portion of the light incident on the primary reflective surface is reflected to the secondary reflective surface and reflected from the secondary reflective surface to a focal line substantially on the primary reflective surface.    
     
     
         2 . The solar concentrator of    claim 1    wherein the primary reflector is positioned relative to the secondary reflector such that light incident on the primary reflector is reflected substantially parallel to a line between the directrix of the secondary reflector and the focus of the secondary reflector.  
     
     
         3 . The solar concentrator of    claim 1    further comprising a support system for rotating said solar concentrator about a rotational axis that is substantially parallel to the focal line and near the primary reflector.  
     
     
         4 . The solar concentrator of    claim 3    wherein the rotational axis is near the focal line.  
     
     
         5 . The solar concentrator of    claim 3    wherein the rotational axis is between the focal line and the secondary reflector.  
     
     
         6 . The solar concentrator of    claim 1    wherein the rotational axis is substantially on the secondary reflector.  
     
     
         7 . The solar concentrator of    claim 1    wherein the primary and secondary reflectors are adjoining.  
     
     
         8 . The solar concentrator of    claim 1    further comprising a solar receiver on the focal line.  
     
     
         9 . A solar concentrator assembly comprising: 
 a parabolic reflector having a parabolic curvature;    a planar reflector being substantially planar and positioned adjacent to the parabolic reflector;    a focal line on one of the parabolic and the planar reflectors; and    a support structure that supports the parabolic and the planar reflectors to rotate together about a rotational axis substantially parallel to the focal line.    
     
     
         10 . The solar concentrator assembly of    claim 9    wherein the rotational axis is near the focal line.  
     
     
         11 . The solar concentrator assembly of    claim 10    wherein the focal line is substantially on the parabolic reflector.  
     
     
         12 . The solar concentrator assembly of    claim 10    wherein the focal line is substantially on the planar reflector.  
     
     
         13 . The solar concentrator assembly of    claim 9    wherein the focal line is substantially on the parabolic reflector and the rotational axis is between the focal line and the planar reflector.  
     
     
         14 . The solar concentrator assembly of    claim 9    wherein the parabolic and the planar reflectors are adjoining.  
     
     
         15 . The solar concentrator assembly of    claim 9    further comprising a solar receiver on the focal line.