Terrestrial solar power system using iii-v semiconductor solar cells

Abstract

A system for generating electrical power from solar radiation utilizing a III-V compound multijunction semiconductor solar cell; a concentrator for focusing sunlight on the solar cell; and a heat spreader connected to the solar cell for cooling the cell. The solar cell is preferably an inverted metamorphic multijunction solar cell.

1 . A system for generating electrical power from solar radiation comprising:
 a thin flexible film III-V compound semiconductor solar cell including first and second electrical contacts on a same side of the solar cell;   a concentrator for focusing sunlight on the solar cell, wherein the concentrator has a non-planer outer surface and a non-planer inner surface;   a solar tracker coupled to said concentrator to align the concentrator with the rays of the sun as the sun traverses the sky so that the rays of the sun are focused on the solar cell;   a heat spreader at the inner surface of the concentrator and connected to said solar cell for cooling said cell; and   an electrical circuit connected to said solar cell for transferring electrical energy from said cell, wherein the thin flexible film solar cell is shaped to conform to the non-planer outer surface of the concentrator on said same side of the solar cell.   
     
     
         2 . A system as defined in  claim 1 , wherein said heat spreader is a metal structure with cooling fins. 
     
     
         3 . A system as defined in  claim 1 , wherein said heat spreader is water cooled. 
     
     
         4 . A system as defined in  claim 1 , wherein said solar cell is an inverted metamorphic cell with an insulated via extending therethrough so that the anode and cathode contacts are on one side thereof. 
     
     
         5 . A system as defined in  claim 1 , further comprising a support module for mounting the solar cell, and a via contact for making electrical contact to one of the first and second electrical contacts. 
     
     
         6 . A system for generating electrical power from solar radiation comprising:
 a thin flexible film III-V compound semiconductor solar cell including first and second electrical contacts on a same side of the solar cell;   an optical concentrator for focusing rays of the sun on the solar cell;   a cylindrical support having an outer surface and an inner surface, wherein the cylindrical support comprises of a first electrically conductive element, a second electrically conductive element electrically isolated from the first electrically conductive element, and a dielectric portion for separating the first and second electrically conductive elements; and   a solar tracker coupled to said optical concentrator to align the concentrator with the rays of the sun as the sun traverses the sky so that the rays of the sun are focused by said optical concentrator on the solar cell,   wherein the thin flexible film solar cell is shaped to conform to the outer surface of the cylindrical support on said same side of the solar cell, and wherein the first electrically conductive element is electrically connected to the first electrical contact and the second electrically conductive element is electrically connected to the second electrical contact.   
     
     
         7 . A system as defined in  claim 6 , further comprising a heat spreader with a metal structure and cooling fins. 
     
     
         8 . A system as defined in  claim 7 , wherein said heat spreader is water cooled. 
     
     
         9 . A system as defined in  claim 6 , wherein said solar cell is an inverted metamorphic cell with an insulated via extending therethrough. 
     
     
         10 . A system as defined in  claim 6 , further comprising a support bracket to suspend the cylindrical tube concentrator a focal point along a line approximately at a center of the cylindrical tube concentrator. 
     
     
         11 . A system as defined in  claim 6 , further comprising a via contact for making electrical contact to one of the first and second electrical contacts. 
     
     
         12 . A system as defined in  claim 6 , further comprising an electrical circuit connected to said solar cell for transferring electrical energy from said cell. 
     
     
         13 . A system as defined in  claim 6 , wherein at least one of the first and second electrically conductive elements is a heat spreader with a metal structure. 
     
     
         14 . A system for generating electrical power from solar radiation comprising:
 a thin flexible film III-V compound semiconductor photovoltaic solar cell including a semiconductor body; a first solar subcell in said body having a first band gap; a second solar subcell in said body disposed adjacent said first subcell in said body and having a second band gap smaller than said first band gap; a grading interlayer disposed adjacent said second subcell in said body and having a third band gap greater than said second band gap; and a third solar subcell disposed adjacent said interlayer in said body and being lattice mismatched with respect to said second subcell and having a fourth band gap smaller than said third band gap;   an optical concentrator for focusing sunlight on the photovoltaic solar cell; and   a cylindrical support having an outer surface and an inner surface and comprising of a first electrically conductive element, a second electrically conductive element electrically isolated from the first electrically conductive element, and a dielectric portion for separating the first and second electrically conductive elements, wherein the thin flexible film solar cell is shaped to conform to the outer surface of the cylindrical support on said same side of the solar cell.   
     
     
         15 . A system as defined in  claim 14 , further comprising a solar tracker coupled to said optical concentrator so as to align the concentrator with the rays of the sun as the sun traverses the sky so that the rays of the sun are focused on the solar cell. 
     
     
         16 . A system as defined in  claim 14 , further comprising an electrical circuit connected to said photovoltaic solar cell for transferring electrical energy from said cell. 
     
     
         17 . A system as defined in  claim 14 , wherein said first solar subcell is composed of InGaAlP. 
     
     
         18 . A system as defined in  claim 14 , wherein said third solar subcell is composed of In 0.30 GaAs. 
     
     
         19 . A system as defined in  claim 14 , wherein the concentrator is a Cassegrain reflector. 
     
     
         20 . A system as defined in  claim 14 , further comprising a heat spreader adjacent said solar cell for cooling said solar cell.