Refrigerator or freezer with enhanced efficiency

Abstract

A refrigerator or a freezer comprises a primary refrigeration system ( 11 ) which is augmented with a passive secondary refrigeration loop ( 15 ) having a condenser ( 30 ) in thermal contact with a primary fluid line ( 12 ) at the location between a primary compressor ( 16 ) and a primary condenser ( 18 ) and preferably placed outside a building so that the passive secondary refrigeration loop ( 15 ) provides cooling to the primary refrigeration system ( 11 ) when the outside temperature is sufficiently low The condenser ( 30 ) of the passive secondary refrigeration loop ( 15 ) is positioned above the points where the primary fluid line ( 12 ) connects with mlet ( 32 ) and outlet ( 34 ) lines of the secondary loop condenser ( 30 )

1 . A refrigerator or freezer comprising:
 a primary refrigeration circuit having a circuit condenser, a circuit evaporator, a circuit compressor, and a circuit fluid line defining a loop which fluidly connects said circuit evaporator to said circuit condenser through said circuit compressor such that said circuit compressor draws refrigerant in said circuit fluid line from said circuit evaporator and pumps said refrigerant toward said circuit condenser;   a passive refrigeration loop or spur comprising a loop or spur condenser;   a loop or spur line fluidly communicating with a lower portion of said loop or spur condenser;   said loop or spur line associated with said fluid line between an outlet of said evaporator and an inlet of said condenser at a location below said loop or spur condenser.   
   
   
       2 . The refrigerator or freezer of  claim 1  wherein said loop or spur line is associated with said circuit line between said circuit compressor and said circuit condenser. 
   
   
       3 . The refrigerator or freezer of  claim 1  wherein said loop or spur line is associated with said circuit line at an outlet of said circuit compressor. 
   
   
       4 . The refrigerator or freezer of  claim 1  wherein said passive refrigeration loop or spur is a loop, said loop or spur condenser is a loop condenser, and said loop or spur line is a loop outlet line and further comprising a loop inlet line extending to an upper portion of said loop condenser, said loop inlet line associated with said circuit line between an outlet of said circuit evaporator and an inlet of said circuit condenser, said loop outlet line associated with said circuit line downstream of said loop inlet line. 
   
   
       5 . The refrigerator or freezer of  claim 4  wherein said loop inlet line is associated with said circuit line between said circuit compressor and said circuit condenser. 
   
   
       6 . The refrigerator or freezer of  claim 4  wherein said loop inlet line is associated with said circuit line at an outlet of said circuit compressor. 
   
   
       7 . The refrigerator or freezer of any one of  claim 4  to  claim 6   claim 4  wherein said loop inlet line and said loop outlet line are fluidly connected at said circuit line through a loop heat exchanger in heat exchange relation with said circuit line. 
   
   
       8 . The refrigerator or freezer of  claim 7  wherein said loop heat exchanger is a spiral tube, one end of which is in fluid communication with said loop outlet line and another end of which is in fluid communication with said loop inlet line, said spiral tube being wound around said circuit line. 
   
   
       9 . The refrigerator or freezer of  claim 4  wherein said loop inlet line is tapped into said circuit line and wherein said loop outlet line is tapped into said fluid line downstream of said loop inlet line. 
   
   
       10 . The refrigerator or freezer of  claim 1  wherein said compressor is a positive displacement compressor. 
   
   
       11 . The refrigerator or freezer of  claim 1  further comprising a shield positioned for shading said loop or spur condenser from sun. 
   
   
       12 . The refrigerator or freezer of  claim 4  further comprising a shield positioned for shading said loop condenser from sun. 
   
   
       13 . The refrigerator or freezer of  claim 1  further comprising a circuit expansion valve between an outlet of said circuit condenser and an inlet of said circuit evaporator. 
   
   
       14 . The refrigerator or freezer of  claim 1  wherein said loop or spur line functions as a loop or spur inlet line and a loop or spur outlet line. 
   
   
       15 . A refrigerator or freezer, comprising:
 a closed primary refrigeration system;   a closed secondary, passive, refrigeration circuit;   said secondary refrigeration circuit having a heat exchanger in heat exchange relation with said primary refrigeration system, said secondary passive refrigeration circuit being one of a heat pipe loop and a thermosiphon loop.   
   
   
       16 . A method of enhancing efficiency of a refrigerator or freezer, comprising:
 positioning a heat exchanger of a passive refrigeration loop having said heat exchanger and a passive loop condenser in heat exchange relation with a waste heat bearing element of a primary refrigeration system of said refrigerator or freezer;   positioning said passive loop condenser outside a building housing said refrigerator or freezer such that said passive loop condenser is exposed to ambient temperature, said passive loop condenser positioned above said heat exchanger.   
   
   
       17 . The method of  claim 16  wherein said passive refrigeration loop is one of a heat pipe loop and a thermosiphon loop. 
   
   
       18 . The method of  claim 16  wherein said passive refrigeration loop is a heat pipe loop, said heat pipe loop comprising a heat pipe line fluidly connecting said heat exchanger with a lower portion of said passive loop condenser. 
   
   
       19 . The method of  claim 18  wherein said heat pipe line is a heat pipe outlet line and further comprising a heat pipe inlet line fluidly connected to said heat pipe outlet line through said heat exchanger, said heat pipe inlet line in fluid communication with said passive loop condenser. 
   
   
       20 . The method of  claim 16  wherein said heat exchanger is a tube and wherein said positioning said heat exchanger comprises winding said tube around said waste heat bearing element. 
   
   
       21 . The method of  claim 16  wherein said primary refrigeration system comprises a primary circuit condenser, a primary circuit evaporator, a primary circuit compressor, and a fluid line defining a loop which fluidly connects said primary circuit evaporator to said primary circuit condenser through said primary circuit compressor such that said primary circuit compressor draws refrigerant in said fluid line from said primary circuit evaporator and pumps said refrigerant toward said primary circuit condenser, said positioning said heat exchanger comprising positioning said heat exchanger at said fluid line between an outlet of said primary circuit evaporator and an inlet of said primary circuit condenser. 
   
   
       22 . The method of  claim 21  wherein said positioning said heat exchanger comprises positioning said heat exchanger at said fluid line between said primary circuit compressor and said primary circuit condenser. 
   
   
       23 . The method of  claim 22  wherein said positioning said heat exchanger comprises positioning said heat exchanger at said fluid line at an outlet of said primary circuit compressor. 
   
   
       24 . The method of  claim 16  further comprising shielding said passive loop condenser from sun.