Solar collector

Abstract

The present invention relates to a solar energy collector suitable for use in a solar energy collection system. The solar energy collection system includes the collector, a stand that supports the collector and a tracking system that causes the collector to track movements of the sun along at least one axis. The collector includes one or more reflector panels, one or more solar receivers, and a space frame support structure that physically supports the reflector panels and solar receivers. In a particular embodiment, the space frame support structure includes struts that extend through a gap between the reflector panels to support the one or more receivers.

What is claimed is: 
     
         1 . A photovoltaic solar energy collector suitable for use in a solar energy collection system that includes the collector, a stand that supports the collector and a tracking system that causes the collector to track movements of the sun along at least one axis, the collector comprising:
 a plurality of reflector panels including first and second reflector panels that are separated by a gap and that extend in a longitudinal direction;   at least one solar receiver that is positioned above the gap between the first and second reflector panels, each solar receiver including at least one photovoltaic cell, the plurality of reflector panels being arranged to direct incident sunlight to the at least one solar receiver; and   a space frame support structure that physically supports the plurality of reflector panels and the at least one solar receiver, the space frame support structure including a multiplicity of linear struts that are connected at nodes to form a repeating geometric pattern wherein the multiplicity of linear struts include a first strut and a second strut that physically support the at least one solar receiver, the first and second struts slanting downward and outward from the at least one solar receiver and extending through the gap between the first and second reflector panels.   
     
     
         2 . A photovoltaic solar energy collector as recited in  claim 1  wherein:
 the reflector panels have concave reflective surfaces that face inward towards a central region of the collector; and 
 there is an aperture between the first and second support struts that allows air to flow therethrough. 
 
     
     
         3 . A photovoltaic solar energy collector as recited in  claim 1  wherein the first and second reflector panels are arranged symmetrically about a reference plane that extends in said longitudinal direction and wherein the first and second struts are also arranged symmetrically about the reference plane. 
     
     
         4 . A solar collector as recited in  claim 1 , further comprising:
 a longeron that extends in said longitudinal direction, the at least one solar receiver being attached with the longeron;   the nodes of the space frame support structure include a plurality of nodes that are separated by gaps and that are arranged along the length of the longeron; and   a plurality of the struts are coupled to each of the nodes on the longeron and extend diagonally downward from the node to help support the at least one solar receiver.   
     
     
         5 . A solar collector as recited in  claim 1 , wherein:
 the first and second reflector panels each include an inner edge and an outer edge that extend in a longitudinal direction, the inner edges of the first and second reflector panels being positioned closer to one another than the outer edges of the first and second reflector panels, the first and second reflector panels being arranged such that the outer edges of the first and second reflector panels are positioned higher than the inner edges of the first and second reflector panels; and   the at least one solar receiver includes first and second solar receivers that are positioned adjacent to one another over a region that is between the inner edges of the first and second reflector panels, respectively.   
     
     
         6 . A solar collector as recited in  claim 5 , wherein:
 the collector further comprises a upper longeron, the first and second struts being connected with and helping to support the upper longeron, the upper longeron being positioned higher than the first and second reflector panels and extending in said longitudinal direction, the first and second solar receivers being mounted on the upper longeron;   the nodes of the space frame support structure includes a plurality of top nodes that are separated by gaps and that are arranged along the length of the upper longeron, the top nodes being positioned higher than the first and second reflector panels; and   the first and second struts are attached to the top node on the upper longeron and extend diagonally downward therefrom to pass between the first and second reflector panels to help support the first and second solar receivers.   
     
     
         7 . A solar collector as recited in  claim 5 , wherein:
 the second solar receiver is positioned over and shades the first solar receiver; and   the second reflector panel is positioned higher than the first reflector panel.   
     
     
         8 . A solar collector as recited in  claim 5 , wherein:
 the plurality of reflector panels further includes a third reflector panel and a fourth reflector panel, each reflector panel having a backside and a reflective frontside, the third reflector panel being positioned outside the outer edge of the first reflector panel, the fourth reflector panel being positioned outside the outer edge of the second reflector panel, each reflector panel having a concave shape that curves outward from a central region between the first and second reflector panels; and   the at least one solar receiver further includes a third solar receiver and a fourth solar receiver, the third and fourth solar receivers being positioned on the backsides of and at the outer edges of the first and second reflector panels, respectively, wherein the reflective frontsides of the third and fourth reflector panels are arranged to direct incident light to the third and fourth solar receivers, respectively.   
     
     
         9 . A solar energy collection system as recited in  claim 1 , wherein each strut is formed from one selected from a group consisting of roll formed steel sections, hot rolled steel sections and tubular aluminum extruded members. 
     
     
         10 . A solar energy collection system as recited in  claim 1 , wherein:
 the collector further comprises an upper longeron that extends in the longitudinal direction and a connector, the connector being an integrally formed metal piece that at least partially encircles and is secured to the upper longeron, the connector having engagement features for receiving the first and second struts;   the solar collector is substantially symmetrical along a bisecting plane; and   the upper longeron and the attached connector are positioned on the bisecting plane.   
     
     
         11 . A photovoltaic solar energy collector as recited in  claim 1  wherein:
 each of the plurality of reflector panels has a concave shape; and 
 the multiplicity of linear struts includes a plurality of reflector support struts that underlie, are adjacent to and physically support the plurality of reflector panels wherein the plurality of reflector support struts are straight and do not match the concave shape of the reflector panel. 
 
     
     
         12 . A photovoltaic solar energy collection system comprising:
 a solar energy collector including,
 at least one reflector panel that extends in a longitudinal direction, 
 at least one solar receiver, each solar receiver including at least one photovoltaic cell, the plurality of reflector panels being arranged to direct incident sunlight to the at least one solar receiver, and 
 a space frame support structure that physically supports the at least one reflector panel and the at least one solar receiver, the space frame support structure including a multiplicity of linear struts that are connected at nodes to form a repeating geometric pattern; and 
   a stand that pivotally supports the collector for pivotal movement around a pivot axis; and   a tracking system that causes the collector to pivot around the pivot axis to track movements of the sun along at least one axis wherein the range of motion around the pivot axis is one selected from a group consisting of: 1) at least 150 degrees; 2) at least 160 degrees; and 3) at least 170 degrees.   
     
     
         13 . A solar energy collection system as recited in  claim 12  wherein the pivot axis is positioned away from the center of gravity of the collector to facilitate said range of motion. 
     
     
         14 . A solar energy collection system as recited in  claim 12  wherein neither the solar receiver nor any support structure in the collector shades the at least one reflector panel. 
     
     
         15 . A photovoltaic solar energy collector suitable for use in a solar energy collection system that includes the collector, a stand that supports the collector and a tracking system that causes the collector to track movements of the sun along at least one axis, the collector comprising:
 at least one reflector panel that extends in a longitudinal direction;   at least one solar receiver, each solar receiver including at least one photovoltaic cell, the plurality of reflector panels being arranged to direct incident sunlight to the at least one solar receiver; and   a space frame support structure that physically supports the at least one reflector panel and the at least one solar receiver, the space frame support structure including a multiplicity of linear struts that are connected at nodes to form a repeating geometric pattern wherein the repeating geometric pattern repeats along the longitudinal axis and wherein the longitudinal period of the repeating geometric pattern does not equal the length of any reflector panel or solar receiver in the collector.   
     
     
         16 . A solar energy collector as recited in  claim 15  further comprising at least one stringer that extends in a longitudinal direction and underlies a reflector panel of the at least one reflector panel, each stringer including a plurality of attachment points for attaching to the overlying reflector panel. 
     
     
         17 . A solar energy collector as recited in  claim 15  wherein:
 the multiplicity of struts further includes a plurality of reflector support struts that extend out from a central region of the collector towards the periphery of the collector; 
 the reflector support struts underlie the reflector panels and the stringers, each stringer being attached with at least two of the reflector support struts. 
 
     
     
         18 . A solar energy collector as recited in  claim 17 , wherein:
 the collector further comprises a central node, an upper longeron, a lower longeron and a side longeron that all extend substantially parallel to one another in a longitudinal direction and that are all connected with one another using at least some of the struts; and   the at least one reflector support strut includes a first reflector support strut and a second reflector support strut, the first reflector support strut extending from the central node in the space frame support structure to the side longeron, the second reflector support strut extending from the lower longeron to the side longeron, wherein the first and second reflector support struts are arranged to help physically support the at least one reflector.