Solar collector

Abstract

The invention provides a solar collector comprising a trough-like reflector for receiving solar rays and for concentrating the rays in a direction generally transverse to the length of the reflector between its ends. Concentrator means is provided for receiving the concentrated rays from the trough-like reflector and for concentrating the rays in one or more of a direction generally along said length and a direction generally transverse to said length.

1 . A solar collector comprising a trough-like reflector for receiving solar rays and for concentrating the rays in a direction generally transverse to the length of the reflector between its ends, and concentrator means for receiving the concentrated rays from the trough-like reflector and for concentrating the rays in one or more of a direction generally along said length and a direction generally transverse to said length. 
     
     
         2 . A solar collector as claimed in  claim 1 , wherein said concentrator means comprises at least one of a refractive element and a reflective element. 
     
     
         3 . A solar collector as claimed in  claim 1 , wherein said concentrator means comprises a plurality of elements positioned relative to one another in a direction along the length of the trough-like reflector. 
     
     
         4 . A solar collector as claimed in  claim 2 , wherein one or more of said elements redirects rays in opposite directions along said length to converge towards a predetermined area. 
     
     
         5 . A solar collector as claimed in  claim 1 , wherein said concentrator means concentrates the received rays from the trough-like reflector in a direction transverse to said length. 
     
     
         6 . A solar collector as claimed in  claim 1 , wherein said concentrator means concentrates solar rays received from the trough-like reflector towards a plurality of discrete areas spaced apart in a direction along the length of the trough-like reflector. 
     
     
         7 . A solar collector as claimed in  claim 6 , further comprising any one or more of a solar cell and an optical waveguide positioned at one or more discrete areas. 
     
     
         8 . A solar collector as claimed in  claim 6 , further comprising a ray distribution device for redistributing rays received from the concentrator means. 
     
     
         9 . A solar collector as claimed in  claim 8 , wherein the distribution device increases the uniformity of rays across at least one discrete said area. 
     
     
         10 . A solar collector as claimed in  claim 6 , wherein one or more of the distribution devices comprises a reflective device having opposed reflective side walls for reflecting solar rays received from the concentrator means. 
     
     
         11 . A solar collector as claimed in  claim 10 , wherein the distribution device is configured to prevent reflection by the reflective walls back towards the concentrator means. 
     
     
         12 . A solar collector as claimed in  claim 6 , wherein the distribution device comprises at least one wall which is angled in the ray direction towards an opposed wall of the distribution device. 
     
     
         13 . A solar collector as claimed in  claim 1 , further comprising one or more conduits for carrying fluid and which is positioned to receive thermal energy from solar rays emitted from the concentrator means. 
     
     
         14 . A solar collector as claimed in  claim 13 , comprising first and second channels extending generally in a direction along the length of the trough-like reflector and means for causing fluid to flow in a first direction along one of said conduits and in the opposite direction along the other conduit. 
     
     
         15 . A solar collector as claimed in  claim 13 , further comprising a plurality of upstanding members spaced apart along the length of the trough-like reflector and being coupled or connected to the conduit or another member which extends substantially continuously between the ends of the solar collector. 
     
     
         16 . A solar collector as claimed in  claim 15 , wherein said concentrator means is coupled to said conduit or said continuously extending member. 
     
     
         17 . A solar collector as claimed in  claim 1 , wherein said concentrator means comprises a plurality of discrete concentrators distributed in a direction along the length of the solar collector and, before thermal expansion, having a space therebetween to accommodate thermal expansion of each discrete concentrator in a direction along its length. 
     
     
         18 . A solar collector as claimed in  claim 17 , wherein a plurality of discrete concentrators are coupled to a common member extending in a direction along the length of the solar collector. 
     
     
         19 . A solar collector as claimed in  claim 1 , further comprising a plurality of discrete substrates positioned end to end in a direction along the length of the solar collector and having a gap therebetween, a plurality of discrete substrates being mounted to a common member extending along the length of the solar collector and optionally mounted on said common member in a manner which allows relative movement between the member and each substrate in a direction along the length of the solar collector. 
     
     
         20 . A solar collector as claimed in  claim 19 , comprising at least one of a solar cell and optical waveguide coupled to a discrete substrate. 
     
     
         21 . A solar collector as claimed in  claim 1 , further comprising filter means for filtering out one or more portions of the solar electromagnetic spectrum. 
     
     
         22 . A solar collector as claimed in  claim 21 , wherein said filter means comprises any one or more of a coating on the trough-like reflector, a coating on the concentrator means, a translucent member between the trough-like reflector and the concentrator means, a translucent member between the concentrator means and a means for receiving solar rays from the concentrator means. 
     
     
         23 . A solar collector as claimed in  claim 21 , wherein the filter means is adapted to filter out at least a portion of ultraviolet light and/or at least a portion of infrared light. 
     
     
         24 . A solar collector as claimed in  claim 21 , wherein said filter is adapted to transmit at least a portion of visible radiation. 
     
     
         25 . A solar collector as claimed in  claim 1 , mounted on a system capable of orienting the longitudinal axis of the solar collector in a plurality of different directions. 
     
     
         26 . A solar collector as claimed in  claim 1 , wherein said solar collector is mounted on a system capable of rotating said collector about a longitudinal axis thereof. 
     
     
         27 . A solar collector as claimed in  claim 1 , wherein a plurality of solar collectors are mounted on a common structure, the common structure enabling the elevation of each solar collector to be controlled individually or collectively such that each collector rotates about a different longitudinal axis and collectively the solar collectors rotate about a common axis which is substantially vertical or upright.