Solar Energy Control

Abstract

A solar energy collection system includes a solar concentrator operative to direct a concentrated solar beam onto a solar receptor. A shutter plate is positioned between the solar concentrator and the solar receptor and is movable from an open position adjacent to the solar beam, to a closed position wherein at least a portion of the solar beam contacts a front face of the shutter plate and is blocked from contacting the receptor. A cooling circuit is operative to circulate a cooling fluid to remove heat from the shutter plate. A shutter drive is operative to move the at least one shutter plate from the open position to the closed position, and a shutter control is operative to stop movement of the shutter plate at a plurality of locations between the open position and the closed position.

1 . For use in a solar energy collection system comprising a solar concentrator operative to direct a concentrated solar beam onto a solar receptor, a solar shutter apparatus adapted to be positioned between the solar concentrator and the solar receptor to selectively block a portion of the solar beam, the apparatus comprising: 
 at least one shutter plate movable from an open position adjacent to the solar beam, to a closed position wherein at least a portion of the solar beam contacts a front face of the shutter plate and is blocked from contacting the receptor;    a cooling circuit operative to circulate a cooling fluid to remove heat from the shutter plate;    a shutter drive operative to move the at least one shutter plate from the open position to the closed position; and    a shutter control connected to the shutter drive and operative to stop movement of the shutter plate at a plurality of locations between the open position and the closed position.    
   
   
       2 . The apparatus of  claim 1  comprising a plurality of shutter plates arranged such that the solar beam passes between the shutter plates, and wherein the shutter drive is operative to move the shutter plates toward each other to the closed position and away from each other to the open position.  
   
   
       3 . The apparatus of  claim 2  wherein the shutter plates are arranged substantially in a plane transverse to the solar beam and pivotally mounted on a shutter frame such that the solar beam passes through a central aperture formed by the shutter plates when in the open position, and wherein the drive is operative to pivot the shutter plates toward each other to the closed position to reduce a size of the central aperture.  
   
   
       4 . The apparatus of  claim 3  comprising a shutter ring rotatably mounted to the shutter frame and wherein the shutter plates are each pivotally mounted at a first portion thereof to the shutter frame and are pivotally connected at a second portion thereof to the shutter ring by a link, and wherein the drive is operative to rotate the shutter ring with respect to the shutter frame to move the shutter plates from the open position to the closed position.  
   
   
       5 . The apparatus of  claim 1  wherein solar beam is cone-shaped and decreases in diameter between the solar concentrator and the solar receptor, and wherein the at least one shutter plate defines a central aperture, and wherein the at least one shutter plate is located in proximity to the solar receptor when in the open position such that the solar beam passes through the central aperture, and is moved toward the solar concentrator to the closed position such that a portion of the solar beam contacts the at least one shutter plate adjacent to the central aperture.  
   
   
       6 . The apparatus of  claim 5  wherein the at least one shutter plate is mounted on a track aligned between the solar concentrator and the solar receptor, and wherein the drive is operative to move the at least one shutter plate along the track.  
   
   
       7 . The apparatus of  claim 1  wherein the cooling circuit comprises a cooling conduit defined by at least one shutter plate and connected to a source of cooling fluid.  
   
   
       8 . The apparatus of  claim 7  wherein the cooling conduit comprises a first hole extending from a first location on an outer edge of the at least one shutter plate to an inner end located inside the at least one shutter plate, and a second hole extending from a second location on an outer edge of the at least one shutter plate to an inner end located inside the at least one shutter plate, such that the first and second holes intersect, and such that cooling fluid circulated into the first hole flows into the second hole.  
   
   
       9 . The apparatus of  claim 8  wherein the first and second holes are located in proximity to the front face of the shutter plate.  
   
   
       10 . The apparatus of  Claim 1  wherein the front face comprises a reflective surface.  
   
   
       11 . The apparatus of  claim 1  wherein the at least one shutter plate is located in proximity to the solar receptor, and wherein a rear face of the at least one shutter plate comprises one of a reflective surface and an insulation layer such that when in the closed position the at least one shutter plate is operative to reduce heat loss from the solar receptor through the at least one shutter plate.  
   
   
       12 . A solar energy collection system comprising: 
 a solar concentrator operative to direct a concentrated solar beam onto a solar receptor;    a shutter plate positioned between the solar concentrator and the solar receptor and movable from an open position adjacent to the solar beam, to a closed position wherein at least a portion of the solar beam contacts a front face of the shutter plate and is blocked from contacting the receptor;    a cooling circuit operative to circulate a cooling fluid to remove heat from the shutter plate;    a shutter drive operative to move the shutter plate from the open position to the closed position; and    a shutter control connected to the shutter drive and operative to stop movement of the shutter plate at a plurality of locations between the open position and the closed position.    
   
   
       13 . The apparatus of  claim 12  comprising a plurality of shutter plates arranged such that the solar beam passes between the shutter plates, and wherein the shutter drive is operative to move the shutter plates toward each other to the closed position and away from each other to the open position.  
   
   
       14 . The apparatus of  claim 13  wherein the shutter plates are arranged substantially in a plane transverse to the solar beam and pivotally mounted on a shutter frame such that the solar beam passes through a central aperture formed by the shutter plates when in the open position, and wherein the drive is operative to pivot the shutter plates toward each other to the closed position to reduce a size of the central aperture.  
   
   
       15 . The apparatus of  claim 14  comprising a shutter ring rotatably mounted to the shutter frame and wherein the shutter plates are each pivotally mounted at a first portion thereof to the shutter frame and are pivotally connected at a second portion thereof to the shutter ring by a link, and wherein the drive is operative to rotate the shutter ring with respect to the shutter frame to move the shutter plates from the open position to the closed position.  
   
   
       16 . The apparatus of  claim 12  wherein solar beam is cone-shaped and decreases in diameter between the solar concentrator and the solar receptor, and wherein the shutter plate defines a central aperture, and wherein the shutter plate is located in proximity to the solar receptor when in the open position such that the solar beam passes through the central aperture, and is moved toward the solar concentrator to the closed position such that a portion of the solar beam contacts the shutter plate adjacent to the central aperture.  
   
   
       17 . The apparatus of  claim 16  wherein the at least one shutter plate is mounted on a track aligned between the solar concentrator and the solar receptor, and wherein the drive is operative to move the at least one shutter plate along the track.  
   
   
       18 . The apparatus of  claim 12  wherein the cooling circuit comprises a cooling conduit defined by at least one shutter plate and connected to a source of cooling fluid.  
   
   
       19 . The apparatus of  claim 18  wherein the cooling conduit comprises a first hole extending from a first location on an outer edge of the at least one shutter plate to an inner end located inside the at least one shutter plate, and a second hole extending from a second location on an outer edge of the at least one shutter plate to an inner end located inside the at least one shutter plate, such that the first and second holes intersect, and such that cooling fluid circulated into the first hole flows into the second hole.  
   
   
       20 . The apparatus of  claim 19  wherein the first and second holes are located in proximity to the front face of the shutter plate.  
   
   
       21 . The apparatus of  claim 12  wherein the front face comprises a reflective surface.  
   
   
       22 . The apparatus of  claim 12  wherein at least one shutter plate is located in proximity to the solar receptor, and wherein a rear face of the at least one shutter plate comprises one of a reflective surface and an insulation layer such that when in the closed position the at least one shutter plate is operative to reduce heat loss from the solar receptor through the at least one shutter plate.