Method of forming a solar collector having multiple composite plies

Abstract

A solar collector for use in concentrating solar rays into a high flux density image is formed from laminate plies. Electricity is produced by superimposing the image onto a concentrated photovoltaic cell. Plies are cut from a composite sheet that is made up of carbon fibers in a thermoset polymer, where the carbon fibers run generally parallel with one another. By varying how the plies are cut from the sheet, carbon fibers in different plies are oriented at alternating angles in the plies. The plies arc stacked to form a laminate, where the carbon fibers in each ply are at an angle with carbon fibers in adjacent plies. The plies may include alignment tabs to control the angle between adjacent plies. Pressing the laminate in a heated die and cooling the die with forced convection and then a fluid bath forms a shell for the solar collector.

What is claimed is: 
     
         1 . A method of forming a solar collector comprising:
 providing a composite comprising substantially parallel elongated carbon fibers disposed in a thermosetting polymer;   forming plies from the composite by cutting the composite into sections;   stacking the plies into a laminate so that carbon fibers in each ply are oriented at an angle with carbon fibers in any adjacent ply;   pressing the laminate into a shape having a concave side and a convex side;   heating the laminate; and   applying a reflective material to the concave side.   
     
     
         2 . The method of  claim 1 , wherein the angle between carbon fibers in any adjacent ply is selected from the group consisting of 0°, 30°, 45°, 60°, and 900. 
     
     
         3 . The method of  claim 1 , wherein the number of plies making up each laminate is selected from the group consisting of 6, 7, 8, 9, 10, 11, and 12. 
     
     
         4 . The method of  claim 1 , further comprising providing tabs on each ply for precisely arranging each ply in the laminate. 
     
     
         5 . The method of  claim 1 , wherein a portion of the step of pressing is a cold press for debulking the laminate that is at a pressure of about 200 psi to about 250 psi and wherein while heating the laminate the pressure is at about 70 psi. 
     
     
         6 . The method of  claim 1 , wherein the laminate is set in a die that is disposed in a platen assembly and wherein the pressure and the heat is applied by the platen assembly. 
     
     
         7 . The method of  claim 6 , further comprising removing the die from the platen assembly, cooling the die with a forced convection flow of fluid and then a fluid bath.