Focused solar energy collection system to increase efficiency and decrease cost

Abstract

An efficient and cost effective system for the collection, concentration, and delivery of disperse solar energy to a central location for use in electrical power generation. The system includes a unique structural design for a strong lightweight parabolic dish heliostat. It couples this heliostat with a small collimating lens (or mirror) and a flat side mirror to redirect the resultant concentrated solar energy beam to a central receiver.

1 . A solar energy reflection and focusing system including:
 A device for reflecting and focusing solar energy onto a reactor or heat absorber for the conversion of solar energy into thermal, chemical, electrical energy   A primary parabolic dish for reflecting and focusing the solar energy   A secondary lens or reflector used to refocus the solar energy to modify the solar beam convergence distance   A tertiary reflector used to aim the solar energy onto a reactor or down mirror   
     
     
         2 . The system of  claim 1  wherein the primary parabolic dish points directly at the sun throughout the day 
     
     
         3 . The system of  claim 1  wherein the primary structure of the parabolic dish heliostat is a uniquely shaped structural truss composed of
 a. a central compression member running through the center of the parabolic dish (projecting both in front and back), 
 b. radial tension members composed of guy wires tying both ends of the central compression member to points on the parabolic minor, and 
 c. the fiberglass sandwich backed parabolic mirror itself acting as a compression member, both radial and axial 
 
     
     
         4 . The system of  claim 1  wherein the parabolic mirror can be segmented or single piece. 
     
     
         5 . The system of  claim 1  wherein a quartz lens is attached near the focal point of the parabolic dish so as to approximately collimate the solar energy from the parabolic dish 
     
     
         6 . The alternative to the system of  claim 1  wherein the quartz lens is fabricated as a fresnel lens 
     
     
         7 . The system of  claim 1  wherein the lens has a rotating ring structure external to the diameter of the lens which provides a means to rotate a tertiary reflector surface about the parabolic dish axis so as to control the direction of the outgoing solar beam when combined with  claim 8 . 
     
     
         8 . The system of  claim 1  wherein the tertiary reflection surface has the capability to tilt about an axis perpendicular to the parabolic dish axis so as to control the direction of the outgoing solar beam when combined with  claim 7 . 
     
     
         9 . The alternative to the system of  claim 1  wherein the quartz lens is replaced with a secondary reflector located inboard of the focal point of the parabolic dish so that the solar energy focuses across the area of the reflector surface 
     
     
         10 . The alternative to the system of  claim 1  wherein the secondary reflector (of  claim 9 ) is an approximately hyperbolic shape so that the solar energy beam is more parallel to the axis of the parabolic dish after reflecting from the parabolic dish and the secondary reflector 
     
     
         11 . The alternative to the system of  claim 1  wherein the lens (or secondary reflector of  claim 9 ) produces a solar energy beam which has the required toe-in angle so that the solar energy beam reaches the reactor head or heat absorber surface at a reduced diameter 
     
     
         12 . The system of  claim 1  wherein the tertiary reflector has an approximately flat surface and is able to rotate about the primary parabolic dish axis and tilt about an axis normal to the primary parabolic dish axis so as to aim the solar energy beam to the reactor head or heat absorber 
     
     
         13 . The system of  claim 1  wherein the parabolic mirror surface is made from radially tapered structural segments attached at the segment edges to form a structural ring 
     
     
         14 . The system of  claim 13  wherein the parabolic mirror segments include vents at the edges in order to spoil any wind loads that the mirror may experience. 
     
     
         15 . The alternative to the system of  claim 1  where the quartz lens is made of commercially available glass materials 
     
     
         16 . A solar energy reflecting and focusing system wherein the helio-stat configuration operates by continuously aiming at the sun thereby eliminating the cosine effect due to angular differences between heliostat aiming axis and the suns rays. 
     
     
         17 . A solar energy reflecting and focusing system wherein the secondary lens or mirror in combination with the tertiary reflector enables a continuous aiming of the solar energy beam at the reactor head or heat absorber; adjusting in response to the motion of the primary parabolic axis as it tracks the sun throughout the day