Abstract:
Disclosed is a method and device for a refrigerant-based thermal energy storage and cooling system with an isolated evaporator coil in a secondary cooling loop. The disclosed embodiments provide a refrigerant-based ice storage system with increased versatility, reliability, lower cost components, reduced power consumption and ease of installation.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application is based upon and claims the benefit of U.S. provisional application No. 61/056,693, entitled “Thermal Energy Storage and Cooling System with Isolated Evaporator Coil,” filed May 28, 2008, the entire disclosure of which is hereby specifically incorporated by reference for all that it discloses and teaches. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    With the increasing demands on peak demand power consumption, ice storage has been utilized to shift air conditioning power loads to off-peak times and rates. A need exists not only for load shifting from peak to off-peak periods, but also for increases in air conditioning unit capacity and efficiency. Current air conditioning units having energy storage systems have had limited success due to several deficiencies, including reliance on water chillers that are practical only in large commercial buildings and have difficulty achieving high-efficiency. In order to commercialize advantages of thermal energy storage in large and small commercial buildings, thermal energy storage systems must have minimal manufacturing costs, maintain maximum efficiency under varying operating conditions, have minimal implementation and operation impact and be suitable for multiple refrigeration or air conditioning applications. Systems for providing stored thermal energy have been previously contemplated in U.S. Pat. No. 4,735,064, U.S. Pat. No. 5,225,526, both issued to Harry Fischer, U.S. Pat. No. 5,647,225 issued to Fischer et al., U.S. Pat. No. 7,162,878 issued to Narayanarnurthy et al., U.S. patent application Ser. No. 11/112,861 filed Apr. 22, 2005 by Narayanamurthy et al., U.S. patent application Ser. No. 11/138,762 filed May 25, 2005 by Narayanamurthy et al., U.S. patent application Ser. No. 11/208,074 filed Aug. 18, 2005 by Narayanamurthy et al., U.S. patent application Ser. No. 11/284,533 filed Nov. 21, 2005 by Narayanamurthy et al., U.S. patent application Ser. No. 11/610,982 filed Dec. 14, 2006 by Narayanamurthy, U.S. patent application Ser. No. 11/837,356 filed Aug. 10, 2007 by Narayanamurthy et al., U.S. Patent Application No. 60/990,685 filed Nov. 28, 2007 by Narayanamurthy et al., and U.S. Patent Application No. 61/029,156 filed Feb. 15, 2008 by Narayanamurthy et al. All of these patents utilize ice storage to shift air conditioning loads from peak to off-peak electric rates to provide economic justification and are hereby incorporated by reference herein for all they teach and disclose. 
       SUMMARY OF THE INVENTION 
       [0003]    An embodiment of the present invention may therefore comprise: a refrigerant-based thermal energy storage and cooling system comprising: a refrigerant loop containing a refrigerant comprising: a condensing unit, the condensing unit comprising a compressor and a condenser; an expansion device connected downstream of the condensing unit; and, a primary heat exchanger connected between the expansion device and the condensing unit that is located within a tank filled with a fluid capable of a phase change between liquid and solid, the primary heat exchanger that performs as an evaporator and facilitates heat transfer from the refrigerant from the condenser to cool the fluid and to freeze at least a portion of the fluid within the tank in a first time period, and the primary heat exchanger that performs as a condenser and facilitates heat transfer from the fluid to cool the refrigerant in a second time period; a cooling loop containing a heat transfer medium comprising: a load heat exchanger; a first isolating heat exchanger that facilitates thermal contact between the refrigerant condensed within the primary heat exchanger and the heat transfer medium, the heat transfer medium that transfers cooling from the first isolating heat exchanger to the load heat exchanger in the second time period; and, a second isolating heat exchanger that facilitates thermal contact between the refrigerant condensed within the condensing unit and the heat transfer medium, the heat transfer medium that transfers cooling from the second isolating heat exchanger to the load heat exchanger in a third time period. 
         [0004]    An embodiment of the present invention may also comprise: a refrigerant-based thermal energy storage and cooling system comprising: a refrigerant loop containing a refrigerant comprising: a condensing unit, the condensing unit comprising a compressor and a condenser; an expansion device connected downstream of the condensing unit; and, a primary heat exchanger connected between the expansion device and the condensing unit that is located within a tank filled with a fluid capable of a phase change between liquid and solid, the primary heat exchanger that performs as an evaporator and facilitates heat transfer from the refrigerant from the condenser to cool the fluid and to freeze at least a portion of the fluid within the tank in a first time period; a cooling loop containing a heat transfer medium comprising: a load heat exchanger; a first isolating heat exchanger that facilitates thermal contact between the fluid and the heat transfer medium, the heat transfer medium that transfers cooling from the first isolating heat exchanger to the load heat exchanger in the second time period; and, a second isolating heat exchanger that facilitates thermal contact between the refrigerant condensed within the condensing unit and the heat transfer medium, the heat transfer medium that transfers cooling from the second isolating heat exchanger to the load heat exchanger in a third time period. 
         [0005]    An embodiment of the present invention may also comprise: a refrigerant-based thermal energy storage and cooling system comprising: a refrigerant loop containing a refrigerant comprising: a condensing unit, the condensing unit comprising a compressor and a condenser; an expansion device connected downstream of the condensing unit; and, a primary heat exchanger connected between the expansion device and the condensing unit that is located within a tank filled with a fluid capable of a phase change between liquid and solid, the primary heat exchanger that performs as an evaporator and facilitates heat transfer from the refrigerant from the condenser to cool the fluid and to freeze at least a portion of the fluid within the tank in a first time period, and the primary heat exchanger that performs as a condenser and facilitates heat transfer from the fluid to cool the refrigerant in a second time period; a cooling loop containing a heat transfer medium comprising: a load heat exchanger; a first isolating heat exchanger that facilitates thermal contact between the fluid and the heat transfer medium, the heat transfer medium that transfers cooling from the first isolating heat exchanger to the load heat exchanger in the second time period; and, a second isolating heat exchanger that facilitates thermal contact between the refrigerant cooled by the fluid within the tank and the heat transfer medium, the heat transfer medium that transfers cooling from the second isolating heat exchanger to the load heat exchanger in a third time period. 
         [0006]    An embodiment of the present invention may also comprise: a method of providing cooling with a thermal energy storage and cooling system comprising: during a first time period: compressing and condensing a refrigerant with an air conditioner unit to create a high-pressure refrigerant; expanding the high-pressure refrigerant to provide cooling in a primary heat exchanger, the primary heat exchanger that is constrained within a tank containing a fluid capable of a phase change between liquid and solid; and, freezing a portion of the fluid and forming ice and cooled fluid within the tank; during a second time period: transferring cooling from the fluid and the ice to the refrigerant within the primary heat exchanger; transferring cooling from the refrigerant cooled within the primary heat exchanger to a heat transfer medium in a cooling loop with a first isolating heat exchanger; and, transferring cooling from the heat transfer medium to a load heat exchanger within the cooling loop to provide load cooling; during a third time period: transferring cooling from the refrigerant from the air conditioner unit to the heat transfer medium in the cooling loop with a second isolating heat exchanger; and, transferring cooling from the heat transfer medium to the load heat exchanger within the cooling loop to provide load cooling. 
         [0007]    An embodiment of the present invention may comprise: a method of providing cooling with a thermal energy storage and cooling system comprising: during a first time period; compressing and condensing a refrigerant with an air conditioner unit to create a high-pressure refrigerant; expanding the high-pressure refrigerant to provide cooling in a primary heat exchanger, the primary heat exchanger that is constrained within a tank containing a fluid capable of a phase change between liquid and solid; and, freezing a portion of the fluid and forming ice and cooled fluid within the tank; during a second time period: transferring cooling from the fluid to a heat transfer medium in a cooling loop with a first isolating heat exchanger; and, transferring cooling from the heat transfer medium to a load heat exchanger within the cooling loop to provide load cooling; during a third time period; transferring cooling from the refrigerant from the air conditioner unit to the heat transfer medium in the cooling loop with a second isolating heat exchanger; and, transferring cooling from the heat transfer medium to the load heat exchanger within the cooling loop to provide load cooling. 
         [0008]    An embodiment of the present invention may also comprise: a method of providing cooling with a thermal energy storage and cooling system comprising: during a first time period: compressing and condensing a refrigerant with an air conditioner unit to create a high-pressure refrigerant; expanding the high-pressure refrigerant to provide cooling in a primary heat exchanger, the primary heat exchanger that is constrained within a tank containing a fluid capable of a phase change between liquid and solid; and, freezing a portion of the fluid and forming ice and cooled fluid within the tank; during a second time period: transferring cooling from the fluid to a heat transfer medium in a cooling loop with a first isolating heat exchanger, and transferring cooling from the heat transfer medium to a load heat exchanger within the cooling loop to provide load cooling; during a third time period: transferring cooling from the fluid and the ice to the refrigerant within the primary heat exchanger; transferring cooling from the refrigerant cooled within the primary heat exchanger to the heat transfer medium in a cooling loop with a second isolating heat exchanger; and, transferring cooling from the heat transfer medium to the load heat exchanger within the cooling loop to provide load cooling. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0009]    In the drawings, 
           [0010]      FIG. 1  illustrates an embodiment of a thermal energy storage and cooling system with an isolated evaporator coil in a secondary cooling loop. 
           [0011]      FIG. 2  illustrates a configuration of another embodiment of a thermal energy storage and cooling system with an isolated evaporator coil in a secondary cooling loop. 
           [0012]      FIG. 3  illustrates a configuration of another embodiment of a thermal energy storage and cooling system with an isolated evaporator coil in a secondary cooling loop. 
           [0013]      FIG. 4  illustrates a configuration of another embodiment of a thermal energy storage and cooling system with an isolated evaporator coil in a secondary cooling loop. 
           [0014]      FIG. 5  illustrates a configuration of another embodiment of a thermal energy storage and cooling system with an isolated evaporator coil in a secondary cooling loop. 
           [0015]      FIG. 6  illustrates a configuration of another embodiment of a thermal energy storage and cooling system with an isolated evaporator coil in a secondary cooling loop. 
           [0016]      FIG. 7  illustrates a configuration of another embodiment of a thermal energy storage and cooling system with an isolated evaporator coil in a secondary cooling loop with subcooling capacity. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0017]    While this invention is susceptible to embodiment in many different forms, it is shown in the drawings, and will be described herein in detail, specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not to be limited to the specific embodiments described. 
         [0018]      FIG. 1  illustrates an embodiment of a thermal energy storage and cooling system with an isolated evaporator coil in a secondary refrigerant loop. This embodiment may function with or without an accumulator vessel or URMV  146  (universal refrigerant management vessel), and is depicted in  FIG. 1  with the vessel in place in the primary refrigerant loop with the air conditioner unit  102 . 
         [0019]    As illustrated in  FIG. 1 , a conventional air conditioner unit  102  utilizes a compressor  110  to compress cold, low pressure refrigerant gas to hot, high-pressure gas. Next, a condenser  111  removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser  111  as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid supply line  112  to the refrigerant management and distribution system  104 , which may optionally include a refrigerant receiver  190  that feeds an expansion device  130  through a three-way valve  186 , to an optional accumulator vessel or URMV  146  acting as a collector and phase separator of multi-phase refrigerant. This expansion device  130  may be a conventional or non-conventional thermal expansion valve, a mixed-phase regulator and surge vessel (reservoir), or the like. Liquid refrigerant is then transferred from the URMV  146  to the thermal energy storage unit  106 . A primary heat exchanger  160  within an insulated tank  140  expands the refrigerant that is fed from a lower header assembly  156  through the freezing/discharge coils  142 , to the upper header assembly  154 . Low-pressure vapor phase and liquid refrigerant is then returned to the URMV  146  and compressor  110  via a low pressure return line  118  from a three-way valve  188  completing the primary refrigeration loop. 
         [0020]    As illustrated in  FIG. 1 , the thermal energy storage unit  106  comprises an insulated tank  140  that houses the primary heat exchanger  160  surrounded by a liquid phase material  152  and/or solid phase material  153  (fluid/ice depending on the current system mode). The primary heat exchanger  160  further comprises a lower header assembly  156  connected to an upper header assembly  154  with a series of freezing and discharge coils  142  to make a fluid/vapor loop within the insulated tank  140 . The upper and lower header assemblies  154  and  156  communicate externally of the thermal energy storage unit  106  with inlet and outlet connections. 
         [0021]    The embodiment illustrated in  FIG. 1  utilizes the air conditioner unit  102  as the principal cooling source for the thermal energy storage unit  106 . This portion of the disclosed embodiment functions in four principal modes of operation, ice-make (charging), ice-melt (cooling) mode, boost mode and bypass mode. 
         [0022]    In ice-make mode, compressed high-pressure refrigerant leaves the air conditioner unit  102  through high-pressure liquid supply line  112  and optional refrigerant receiver  190 , and is fed through an expansion device  130  through three-way valve  186  and URMV  146  to cool the thermal energy storage unit  106 . Here the refrigerant enters the primary heat exchanger  160  through the lower header assembly  156  and is then distributed through the freezing coils  142  which act as an evaporator. Cooling is transmitted from the freezing coils  142  to the surrounding liquid phase material  152  that is confined within the insulated tank  140  and may produce a block of solid phase material  153  (ice) surrounding the freezing coils  142  and storing thermal energy in the process. Warm liquid and vapor phase refrigerant leaves the freezing coils  142  through the upper header assembly  154  and exits the thermal energy storage unit  106  returning to the URMV  146  and then through three-way valve  188  to the air conditioner unit  102  through the low pressure return line  118  and is fed to the compressor  110  and re-condensed into liquid by condenser  111 . 
         [0023]    In ice-melt mode, cool liquid refrigerant leaves the lower portion of the insulated tank  140  via lower header assembly  156  and is propelled by a thermosiphon or optional pump  121  to the primary side of an isolating heat exchanger  162  where cooling is transferred to a secondary refrigerant/cooling loop or cooling circuit  108  on the secondary side of the isolating heat exchanger  162 . Warm vapor or liquid/vapor mixture leaves the primary side of isolating heat exchanger  162  where the refrigerant is returned to the upper header assembly  154  of the thermal energy storage unit  106  and draws cooling from the solid phase change material  153  and or liquid phase change material  152  surrounding the coils. 
         [0024]    The secondary side of the isolating heat exchanger  162  contains a heat transfer medium which may be either coolant or refrigerant that has been cooled by the primary side and leaves the heat exchanger and propelled by thermosiphon or optional pump  120  through a three-way valve  182  to a load heat exchanger  122  where cooling is transferred to a load. Upon leaving the load heat exchanger  122 , the warm refrigerant returns through a three-way valve  180  back to the secondary side of the isolating heat exchanger  162  where it is again cooled and/or condensed. 
         [0025]    In bypass mode, the air conditioner unit  102  utilizes compressor  110  to compress cold, low pressure refrigerant gas to hot, high-pressure gas. Next, a condenser  111  removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser  111  as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid line  112  to an optional refrigerant receiver  190 . Liquid refrigerant is then transferred to an expansion device  130  and then proceeds through a three-way valve  186  to a primary side of the isolating heat exchanger  165  and returns to the air conditioner unit  102  via low pressure return line  118  through another three-way valve  188 . In this mode, cooling is transferred from the expanded refrigerant on the primary side to the secondary side of the isolating heat exchanger  165  and to the cooling circuit  108 . The secondary side of the isolating heat exchanger  165  contains coolant or refrigerant that has been cooled by the primary side, and leaves the heat exchanger and propelled by thermosiphon or optional pump  120  to a load heat exchanger  122  where cooling is transferred to a load. Upon leaving the load heat exchanger  122 , the warm heat transfer medium (refrigerant/coolant) returns through a first three-way valve  180  and through a second three-way valve  182  and back to the secondary side of the isolating heat exchanger  165  where it is again cooled and/or condensed. 
         [0026]    In bypass mode, the system performs in the same manner as a conventional air conditioning system and may operate independent of the thermal energy storage unit. 
         [0027]    Additional cooling may be provided within the embodiment of  FIG. 1  by utilizing the capacity of stored thermal energy from the ice make mode in a combined ice melt and bypass mode or boost mode. In this mode, the air conditioner unit  102  utilizes compressor  110  to compress cold, low pressure refrigerant gas to hot, high-pressure gas. Next, a condenser  111  removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser  111  as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid line  112  to an optional refrigerant receiver  190 . Liquid refrigerant is then transferred to an expansion device  130  and then proceeds through a three-way valve  186  to a primary side of the isolating heat exchanger  165  and returns to the air conditioner unit  102  via low pressure return line  118  through three-way valve  188 . In this mode, cooling is transferred from the expanded refrigerant on the primary side to the secondary side of the isolating heat exchanger  165 . 
         [0028]    In addition to the cooling that is being provided to the cooling circuit  108  by direct influence of the air conditioner unit  102 , stored thermal energy from the ice make mode present in the thermal energy storage unit  106  may be utilized to provide additional cooling to the cooling circuit  108 . This boost cooling is accomplished in the same manner as in ice-melt mode, where cool liquid refrigerant leaves the lower portion of the insulated tank  140  via lower header assembly  156  and is propelled by a thermosiphon or optional pump  121  to the primary side of an isolating heat exchanger  162  where cooling is transferred to a secondary refrigerant/cooling loop or cooling circuit  108  on the secondary side of the isolating heat exchanger  162 . Warm liquid, vapor or liquid/vapor mixture leaves the primary side of isolating heat exchanger  162  where the refrigerant is returned to the upper header assembly  154  of the thermal energy storage unit  106  drawing cooling from the solid phase change material  153  and or liquid phase change material  152  surrounding the coils. 
         [0029]    The cooling circuit  108  that contains a heat transfer medium (coolant or refrigerant) that has been cooled by the primary side of isolating heat exchanger  162  (supplied by cooling from the thermal energy storage unit  106 ). It is clear from these disclosures that the use of a coolant or heat transfer fluid can either keep its phase and stay liquid or gaseous, or can undergo a phase change, with the latent heat adding to the cooling efficiency within the cooling circuit. In circumstances where there is no crossover between the primary refrigerant circuit (compressor  110 ) and the cooling circuit  108 , the heat transfer medium may be a conventional fluid that may remain fluid such as water, glycol, brine, or the like. In circumstances where there is crossover between the primary refrigerant circuit (compressor  110 ) and the cooling circuit  108 , the heat transfer medium may be a conventional commercial refrigerant. The material leaves the isolating heat exchanger  162  and is propelled by thermosiphon or optional pump  120  through three-way valve  182  to the secondary side of a second isolating heat exchanger  165  (supplied by cooling from the air conditioner unit  102 ). Cooling is then transferred to the load heat exchanger  122  where cooling is transferred to a load. Upon leaving the load heat exchanger  122 , the warm refrigerant returns through a three-way valve  180  and back to the secondary side of the first isolating heat exchanger  162  and second isolating heat exchanger  165  where it is again cooled and/or condensed. 
         [0030]    In this mode the system may utilize a relatively small capacity air conditioner and have the ability to deliver high capacity cooling utilizing thermal energy storage. This variability may be further extended by specific sizing of the compressor and condenser components within the system. 
         [0031]    The embodiment illustrated in  FIG. 2  shows a thermal energy storage unit  106  that operates using a refrigerant loop that transfers the cooling between the air conditioner unit  102  and the thermal energy storage unit  106  as in the embodiment of  FIG. 1 . This embodiment may function with or without an accumulator vessel or URMV  146  (universal refrigerant management vessel), and is depicted in  FIG. 2  with the vessel in the primary refrigerant loop. In this example, acting as a collector and phase separator of multi-phase refrigerant, the accumulator or universal refrigerant management vessel (URMV)  146 , is in fluid communication with both the thermal energy storage unit  106  and the air conditioner unit  102 . 
         [0032]    This embodiment also functions in four principal modes of operation: ice-make (charging), ice-melt (cooling), ice-melt/boost (high capacity cooling), and bypass mode. Ice-make mode in the primary refrigerant loop utilizing an air conditioner unit  102  is identical to that of  FIG. 1 . 
         [0033]    In ice-melt mode, the entirety of the fluid is not frozen within the insulated tank  140 , and therefore, an amount of fluid (liquid phase material  152 ) continuously surrounds the block of ice (solid phase material  153 ). At the bottom of the tank, this fluid is very near the freezing point of the medium and this liquid phase material  152  is propelled by a thermosiphon, or optional pump  121  to a primary side of an isolating heat exchanger  162  where cooling is transferred to a secondary side containing a cooling circuit  108 . Warm liquid phase material  152  is then returned to an upper portion of the insulated tank  140  where it is again cooled by the medium within the tank. 
         [0034]    The secondary side of the isolating heat exchanger  162  contains a heat transfer medium which may be either refrigerant (warm vapor or liquid/vapor mixture) or coolant that is cooled by the primary side leaves the heat exchanger where it is propelled by thermosiphon or optional pump  120  through a 3-way valve  182  and to a load heat exchanger  122  where cooling is transferred to a load. Upon leaving the load heat exchanger  122 , the warm vapor phase refrigerant or coolant returns through another 3-way valve  180  to the secondary side of the isolating heat exchanger  162  where it is again cooled. 
         [0035]    In bypass mode, the system performs in the same manner as the embodiment of  FIG. 1  which acts as a conventional air conditioning system and may operate independent of the thermal energy storage unit. 
         [0036]    In a manner similar to the embodiment of  FIG. 1 , ice-melt/bypass or boost mode (high capacity cooling), the primary refrigerant loop driven by air conditioner unit  102  can again continue to cool, can be shut down, or can be disengaged. In addition to the cooling provided by ice-melt from the thermal energy storage unit  106 , air conditioner unit  102  may operate to additionally boost the cooling provided to the load heat exchanger  122 . When in operation, the air conditioner unit  102  utilizes a compressor  110  to compress cold, low pressure refrigerant gas to hot, high-pressure gas. Next, a condenser  111  removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser  111  as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid line  112  through an optional refrigerant receiver  190  to an expansion valve  130 . This expansion device  130  may be a conventional or non-conventional thermal expansion valve, a mixed-phase regulator and surge vessel (reservoir) or the like. 
         [0037]    Refrigerant is metered and regulated by expansion valve  130  and transferred to a 3-way valve  186 . Upon leaving the 3-way valve  186 , refrigerant flows to the primary side of the isolating heat exchanger  165  where cooling is transferred to the secondary side. Warm vapor or liquid/vapor mixture refrigerant leaves the primary side of the isolating heat exchanger  165  and returned to the air conditioner unit  102  through another three-way valve  188  via low pressure return line  118 . 
         [0038]    With both the thermal energy storage unit  106  and the air conditioner unit  102  operating in conjunction, a very high cooling capacity is realized within the system. The cooling circuit  108  that contains coolant or refrigerant that has been cooled by the primary side of isolating heat exchanger  162  (supplied by cooling from the thermal energy storage unit  106 ). The material leaves the isolating heat exchanger  162  and is propelled by thermosiphon or optional pump  120  through three-way valve  182  to the secondary side of a second isolating heat exchanger  165  (supplied by cooling from the air conditioner unit  102 ). Cooling is then transferred to the load heat exchanger  122  where cooling is transferred to a load. Upon leaving the load heat exchanger  122 , the warm refrigerant returns through a three-way valve  180  and back to the secondary side of the first isolating heat exchanger  162  and second isolating heat exchanger  165  where it is again cooled and/or condensed. 
         [0039]      FIG. 3  illustrates an embodiment of a thermal energy storage and cooling system with an isolated evaporator coil in a secondary refrigerant loop. This embodiment may function with or without an accumulator vessel or URMV  146  (universal refrigerant management vessel), and is depicted in  FIG. 3  with the vessel in place in the primary refrigerant loop with the air conditioner unit  102 . 
         [0040]    As illustrated in  FIG. 3 , a conventional air conditioner unit  102  utilizes a compressor  110  to compress cold, low pressure refrigerant gas to hot, high-pressure gas. Next, a condenser  111  removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser  111  as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid supply line  112  to the refrigerant management and distribution system  104 , which may optionally include a refrigerant receiver  190  that feeds an expansion device  130  through a four-way valve  192 , to an optional accumulator vessel or URMV  146  acting as a collector and phase separator of multi-phase refrigerant. This expansion device  130  may be a conventional or non-conventional thermal expansion valve, a mixed-phase regulator and surge vessel (reservoir), or the like. Liquid refrigerant is then transferred from the URMV  146  to the thermal energy storage unit  106 . A primary heat exchanger  160  within an insulated tank  140  expands the refrigerant that is fed from a lower header assembly  156  through the freezing/discharge coils  142 , to the upper header assembly  154 . Low-pressure vapor phase and liquid refrigerant is then returned to the URMV  146  and compressor  110  via a low pressure return line  118  from a four-way valve  194  completing the primary refrigeration loop. 
         [0041]    As illustrated in  FIG. 3 , the thermal energy storage unit  106  comprises an insulated tank  140  and is substantially similar to that described in the embodiment of  FIG. 1 . This current embodiment utilizes the air conditioner unit  102  as the principal cooling source for the thermal energy storage unit  106 . This portion of the disclosed embodiment functions in five principal modes of operation, ice-make (charging), ice-melt (cooling) mode, isolated bypass mode, direct bypass and boost bypass mode. 
         [0042]    In ice-make mode, compressed high-pressure refrigerant leaves the air conditioner unit  102  through high-pressure liquid supply line  112  and optional refrigerant receiver  190 , and is fed through an expansion device  130  through four-way valve  1192  and URMV  146  to cool the thermal energy storage unit  106 . Here the refrigerant enters the primary heat exchanger  160  through the lower header assembly  156  and is then distributed through the freezing coils  142  which act as an evaporator. Cooling is transmitted from the freezing coils  142  to the surrounding liquid phase material  152  that is confined within the insulated tank  140  and may produce a block of solid phase material  153  (ice) surrounding the freezing coils  142  and storing thermal energy in the process. Warm liquid and vapor phase refrigerant leaves the freezing coils  142  through the upper header assembly  154  and exits the thermal energy storage unit  106  returning to the URMV  146  and then through four-way valve  194  to the air conditioner unit  102  through the low pressure return line  118  and is fed to the compressor  110  and re-condensed into liquid by condenser  111 . 
         [0043]    In ice-melt mode, the system operates substantially similar to the embodiment described in  FIG. 1 . 
         [0044]    In isolated bypass mode, the air conditioner unit  102  utilizes compressor  110  to compress cold, low pressure refrigerant gas to hot, high-pressure gas. Next, a condenser  111  removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser  111  as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid line  112  to an optional refrigerant receiver  190 . Liquid refrigerant is then transferred to an expansion device  130  and then proceeds through a four-way valve  192  to a primary side of the isolating heat exchanger  165  and returns to the air conditioner unit  102  via low pressure return line  118  through another four-way valve  194 . In this mode, cooling is transferred from the expanded refrigerant on the primary side to the secondary side of the isolating heat exchanger  165  and to the cooling circuit  108 . The secondary side of the isolating heat exchanger  165  contains coolant or refrigerant that has been cooled by the primary side, and leaves the heat exchanger and propelled by thermosiphon or optional pump  120  to a load heat exchanger  122  where cooling is transferred to a load. Upon leaving the load heat exchanger  122 , the warm refrigerant returns through a first three-way valve  180  and through a second three-way valve  182  and back to the secondary side of the isolating heat exchanger  165  where it is again cooled and/or condensed. 
         [0045]    In direct bypass mode, the refrigerant leaves the condenser  111  delivered through a high-pressure liquid line  112  to an optional refrigerant receiver  190 . Liquid refrigerant is then transferred to an expansion device  130  and then proceeds through a four-way valve  192  to the load heat exchanger  122  via a three-way valve  186  where cooling is delivered to a load. Warm vapor or mixed phase refrigerant leaves the load heat exchanger  122  proceeds through a three-way valve  188  to a four-way valve  194  and returns to the air conditioner unit  102  via low pressure return line  118 . In this manner the system performs as a conventional air conditioning system and may operate independent of the thermal energy storage unit. Optionally, refrigerant leaving the load heat exchanger  122  may be plumbed to enter between valve  187  and URMV  146  to utilize the phase separation capabilities of the URMV  146  prior to transfer to the air conditioner unit  102  via low pressure return line  118 . 
         [0046]    Additional cooling may be provided within the embodiment of  FIG. 3  by utilizing the capacity of stored thermal energy from the ice make mode in a combined ice melt and bypass mode or boost bypass mode. In this mode, high pressure refrigerant gas leaves the air conditioner unit  102  through a high-pressure liquid line  112  to an optional refrigerant receiver  190 . Refrigerant is then transferred to an expansion device  130  and then proceeds through the four-way valve  192  to a primary side of the isolating heat exchanger  165  and returns to the air conditioner unit  102  via low pressure return line  118  through another four-way valve  194 . In this mode, cooling is transferred from the expanded refrigerant on the primary side to the secondary side of the isolating heat exchanger  165  to the cooling circuit  108 . 
         [0047]    In addition to the cooling that is being provided to the cooling circuit  108  by direct influence of the air conditioner unit  102 , stored thermal energy from the ice make mode present in the thermal energy storage unit  106  may be utilized to provide additional cooling to the cooling circuit  108 . This boost cooling is accomplished in the same manner as in ice-melt mode, where cool liquid refrigerant leaves the lower portion of the insulated tank  140  via lower header assembly  156  and is propelled by a thermosiphon or optional pump  121  to the primary side of an isolating heat exchanger  162  where cooling is transferred to a secondary refrigerant/cooling loop or cooling circuit  108  on the secondary side of the isolating heat exchanger  162 . Warm vapor or liquid/vapor mixture leaves the primary side of isolating heat exchanger  162  where the refrigerant is returned to the upper header assembly  154  of the thermal energy storage unit  106  drawing cooling from the solid phase change material  153  and or liquid phase change material  152  surrounding the coils. 
         [0048]    The cooling circuit  108  contains refrigerant that has been cooled by the primary side of isolating heat exchanger  162  (supplied by cooling from the thermal energy storage unit  106 ) and further cooled by the primary side of isolating heat exchanger  165  (supplied by cooling from the air conditioning unit  102 ). The material leaves the isolating heat exchanger  162  and is propelled by thermosiphon or optional pump  120  through three-way valve  186  to the secondary side of a second isolating heat exchanger  165 . Cooling is then transferred to the load heat exchanger  122  where cooling is transferred to a load. Upon leaving the load heat exchanger  122 , the warm refrigerant returns through a three-way valve  180  and back to the secondary side of the first isolating heat exchanger  162  and second isolating heat exchanger  165  where it is again cooled and/or condensed. 
         [0049]    The embodiment illustrated in  FIG. 4  shows a thermal energy storage unit  106  that operates using a refrigerant loop that transfers the cooling between the air conditioner unit  102  and the thermal energy storage unit  106  as in the embodiment of  FIG. 2 . This embodiment may function with or without an accumulator vessel or URMV  146  (universal refrigerant management vessel), and is depicted in  FIG. 4  with the vessel in the primary refrigerant loop. In this example, the URMV  146  is in fluid communication with both the thermal energy storage unit  106  and the air conditioner unit  102 . 
         [0050]    As with the embodiment detailed in  FIG. 3 , the embodiment of  FIG. 4  functions in five principal modes of operation: ice-make (charging), ice-melt (cooling) mode, isolated bypass mode, direct bypass and boost bypass mode. Operation of the ice-make mode in the primary refrigerant loop utilizing an air conditioner unit  102 , and the ice-melt mode utilizing the isolating heat exchanger  165  interfacing with the cooling circuit  108  is substantially similar to the embodiment of  FIG. 2 . 
         [0051]    In isolated bypass mode, the refrigerant leaves the air conditioner unit  102  as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid line  112  to an optional refrigerant receiver  190 . Liquid refrigerant is then transferred to an expansion device  130  and then proceeds through a four-way valve  192  to a primary side of the isolating heat exchanger  165  and returns to the air conditioner unit  102  via low pressure return line  118  through another four-way valve  194 . In this mode, cooling is transferred from the expanded refrigerant on the primary side to the secondary side of the isolating heat exchanger  165  and to the cooling circuit  108 . The secondary side of the isolating heat exchanger  165  contains refrigerant that has been cooled by the primary side, and leaves the heat exchanger and propelled by thermosiphon or optional pump  120  to a load heat exchanger  122  where cooling is transferred to a load. Upon leaving the load heat exchanger  122 , the warm refrigerant returns through a first and second three-way valve  188  and  180  and through a third three-way valve  182  and back to the secondary side of the isolating heat exchanger  165  where it is again cooled and/or condensed. 
         [0052]    In a manner similar to the embodiment of  FIG. 2 , in ice-melt/isolated bypass or boost bypass mode (high capacity cooling), the primary refrigerant loop is driven by air conditioner unit  102  which can again continue to cool, can be shut down, or can be disengaged. In addition to the cooling provided by ice-melt from the thermal energy storage unit  106 , air conditioner unit  102  may operate to additionally boost the cooling provided to the load heat exchanger  122 . When in operation, the air conditioner unit  102  provides refrigerant that leaves the condenser  111  as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid line  112  through an optional refrigerant receiver  190  to an expansion valve  130 . This expansion device  130  may be a conventional or non-conventional thermal expansion valve, a mixed-phase regulator and surge vessel (reservoir) or the like. 
         [0053]    Refrigerant is metered and regulated by expansion valve  130  and transferred to a four-way valve  192 . The refrigerant then flows to the primary side of the isolating heat exchanger  165  where cooling is transferred to the secondary side. Warm vapor or liquid/vapor mixture refrigerant leaves the primary side of the isolating heat exchanger  165  and returned to the air conditioner unit  102  through another four-way valve  194  via low pressure return line  118 . 
         [0054]    With both the thermal energy storage unit  106  and the air conditioner unit  102  operating in conjunction, a very high cooling capacity is realized within the system. The cooling circuit  108  contains refrigerant that may be cooled by the primary side of isolating heat exchanger  162  (supplied by cooling from the thermal energy storage unit  106 ). The material leaves the isolating heat exchanger  162  and is propelled by thermosiphon or optional pump  120  through three-way valve  182  to the secondary side of the second isolating heat exchanger  165  (supplied by cooling from the air conditioner unit  102 ). Cooling is then transferred to the load heat exchanger  122  where cooling is transferred to a load. Upon leaving the load heat exchanger  122 , the warm refrigerant returns through two three-way valves  188  and  180  and back to the secondary side of the first isolating heat exchanger  162  and second isolating heat exchanger  165  where it is again cooled and/or condensed. 
         [0055]    In direct bypass mode, the refrigerant leaves the air conditioner unit  102  and is delivered through a high-pressure liquid line  112  to an optional refrigerant receiver  190 . Liquid refrigerant is then transferred to an expansion device  130  and then proceeds through a four-way valve  192  to the load heat exchanger  122  via a three-way valve  186  where cooling is delivered to a load. Warm vapor or mixed phase refrigerant leaves the load heat exchanger  122  proceeds through a three-way valve  188  to a four-way valve  194  and returns to the air conditioner unit  102  via low pressure return line  118 . In this manner the system performs as a conventional air conditioning system and may operate independent of the thermal energy storage unit. Optionally, refrigerant leaving the load heat exchanger  122  may be plumbed to enter between valve  187  and URMV  146  to utilize the phase separation capabilities of the URMV  146  prior to transfer to the air conditioner unit  102  via low pressure return line  118 . 
         [0056]    The embodiment illustrated in  FIG. 5  shows a thermal energy storage unit  106  that operates using a refrigerant loop that transfers the cooling between the air conditioner unit  102  and the thermal energy storage unit  106  as in the embodiment of  FIG. 2  with additional valves to isolate the air conditioner unit  102  and the expansion device from the thermal energy storage unit  106 . This embodiment may function with or without an accumulator vessel or URMV  146  (universal refrigerant management vessel), and is depicted in  FIG. 5  with the vessel in the primary refrigerant loop. In this example, acting as a collector and phase separator of multi-phase refrigerant, the accumulator or universal refrigerant management vessel (URMV)  146 , is in fluid communication with both the thermal energy storage unit  106  and the air conditioner unit  102 . 
         [0057]    This embodiment functions in four principal modes of operation: ice-make (charging), internal ice-melt (refrigerant cooling), external ice-melt (coolant cooling) and internal/external ice melt (high capacity cooling). Ice-make mode in the primary refrigerant loop utilizing an air conditioner unit  102  is substantially similar to that of  FIG. 1  with valves  185  and  187  open and valves  183  and  184  closed. External ice-melt mode utilizing the isolating heat exchanger  162  interfacing with the cooling circuit  108  is substantially similar to the embodiment of  FIG. 2 . 
         [0058]    In internal ice-melt mode, refrigerant leaves lower header assembly as cool liquid refrigerant delivered through valve  184  and is driven by an optional pump  123  or thermosiphon to a primary side of an isolating heat exchanger  165 . Upon exchanging cooling to the secondary side of this isolating heat exchanger  165 , warm refrigerant is fed through valve  183  and back to the upper header assembly  154 . Here the refrigerant is cooled and condensed by the transfer of cooling from the solid and liquid phase change material  152 ,  153  to the freezing/discharge coils  142  of the primary heat exchanger  160 . In this mode valves  185  and  187  are closed. 
         [0059]    The cooling circuit  108  contains coolant or refrigerant that has been cooled by the primary side of isolating heat exchanger  165  (supplied by refrigerant cooling from the thermal energy storage unit  106 ). The material leaves the isolating heat exchanger  165  and is propelled by thermosiphon or optional pump  120  to the load heat exchanger  122  where cooling is transferred to a load. Upon leaving the load heat exchanger  122 , the warm refrigerant returns through a three-way valves  180  and  182  back to the secondary side of the isolating heat exchanger  165  where it is again cooled and/or condensed. 
         [0060]    In internal/external ice melt mode, high capacity cooling can be transferred to the load heat exchanger  122  by both isolating heat exchangers  162  and  165  at the same time. In this mode, first isolating heat exchanger  162  transfers cooling from the fluid surrounding the ice (external melt cooling) while the second isolating heat exchanger  165  transfers cooling from the refrigerant cooled by the primary heat exchanger  160  within the ice (internal melt cooling). Each isolating heat exchanger  162 ,  165  can simultaneously transfer cooling to the cooling circuit  108  and to the load heat exchanger  122 . While in this or other modes, air conditioner unit  102  can continue to cool, can be shut down, or can be disengaged during the ice melt modes. Additionally the ice melt loops (refrigerant or coolant) may be run in either direction. 
         [0061]    The embodiment illustrated in  FIG. 6  shows a thermal energy storage unit  106  that operates using a refrigerant loop that transfers the cooling between the air conditioner unit  102  and the thermal energy storage unit  106  as in the embodiment of  FIG. 5  with an additional bypass loop that allows the air conditioner unit  102  to deliver cooling directly to the load heat exchanger  122 . This embodiment may also function with or without an accumulator vessel or URMV  146  (universal refrigerant management vessel), and is depicted in  FIG. 6  with the vessel in the primary refrigerant loop. 
         [0062]    This embodiment functions in six principal modes of operation: ice-make (charging), internal ice-melt (refrigerant cooling), external ice-melt (coolant cooling), internal/external ice melt (high capacity cooling), bypass and bypass/boost mode. Ice-make mode in the primary refrigerant loop utilizing an air conditioner unit  102  is substantially similar to that of  FIG. 5  with additional three-way valves  188  and  186  open to the URMV  146  and closed to the load heat exchanger  122 . External ice-melt mode utilizing the isolating heat exchanger  162  interfacing with the cooling circuit  108  is substantially similar to the embodiment of  FIG. 5 . Similarly, the internal ice-melt mode utilizing the isolating heat exchanger  165  interfacing with the cooling circuit  108  is also substantially similar to the embodiment of  FIG. 5 . 
         [0063]    The cooling circuit  108  that contains refrigerant that has been cooled by the primary side of either isolating heat exchanger  163 ,  165  operates in the same manner as the embodiment of  FIG. 5  with the addition of two three-way valves  186 ,  188  placed on either side of the load heat exchanger  122 . 
         [0064]    In bypass mode, refrigerant leaves the condenser  111  delivered through a high-pressure liquid line  112  to an optional refrigerant receiver  190 . Liquid refrigerant is then transferred to an expansion device  130  and then proceeds through a three-way valve  196  to the load heat exchanger  122  via a three-way valve  186  where cooling is delivered to a load. Warm vapor or mixed phase refrigerant leaves the load heat exchanger  122  proceeds through a three-way valve  188  to another three-way valve  198  and returns to the air conditioner unit  102  via low pressure return line  118 . In this manner the system performs as a conventional air conditioning system and may operate independent of the thermal energy storage unit. Optionally, three-way valve  198  may be placed between valve  187  and URMV  146  to utilize the phase separation capabilities of the URMV  146  prior to transfer to the air conditioner unit  102  via low pressure return line  118 . 
         [0065]    In bypass/boost mode, refrigerant is delivered directly to the load heat exchanger  122  in a substantially similar manner as in bypass mode. In addition to this cooling that is delivered by the air conditioner unit  102 , either or both isolating heat exchangers  163 ,  165  may be used to deliver additional cooling form the thermal energy storage unit  106  (internal and/or external melt cooling) to the load heat exchanger  122 . 
         [0066]    The embodiment illustrated in  FIG. 7  shows a thermal energy storage unit  106  that operates using a refrigerant loop that transfers the cooling between the air conditioner unit  102  and the thermal energy storage unit  106  as in the embodiment of  FIG. 6  with an additional loop that allows the thermal energy storage unit  106  to subcool refrigerant exiting the air conditioner unit  102 . This embodiment may also function with or without an accumulator vessel or URMV  146  (universal refrigerant management vessel), and is depicted in  FIG. 7  with the vessel in the primary refrigerant loop. 
         [0067]    This embodiment functions in seven principal modes of operation: ice-make (charging), internal ice-melt (refrigerant cooling), external ice-melt (coolant cooling), internal/external ice melt (high capacity cooling), bypass, bypass/boost mode and bypass/subcool mode. Ice-make (charging), internal ice-melt (refrigerant cooling), external ice-melt (coolant cooling), internal/external ice melt (high capacity cooling), bypass and bypass/boost modes are substantially similar to those same modes as described in the embodiment of  FIG. 6  with the addition of three-way valve  199  and four-way valve  200  in the cooling circuit  108 . 
         [0068]    In bypass/subcool mode, refrigerant leaves the condenser  111  and enters the primary side of subcooling heat exchanger  166  and then is fed to an expansion device  130  and is delivered through a high-pressure liquid line  112  to an optional refrigerant receiver  190 . Liquid refrigerant is then proceeds through a three-way valve  196  to the load heat exchanger  122  via a three-way valve  186  where cooling is delivered to a load. Warm vapor or mixed phase refrigerant leaves the load heat exchanger  122  proceeds through a three-way valve  188  where a portion of the refrigerant is returned to the air conditioner unit  102  optionally through URMV  146  and via low pressure return line  118 , while another portion of the refrigerant may be sent to a four-way valve  200  and through the secondary side of the isolating heat exchanger  162 . Here, the refrigerant is subcooled by the primary side of the isolating heat exchanger  162  which draws cooling from the liquid phase change material  152  within the thermal energy storage unit  106 . Optional or additional subcooling may be delivered to the refrigerant by the other isolating heat exchanger  165  connected to the first isolating heat exchanger  162  via three way valve  182 . After the refrigerant is subcooled in the secondary side isolating heat exchanger  165  by the primary side of isolating heat exchanger  165 , which draws cooling from the refrigerant cooled by the solid phase change material  153 , the subcooled refrigerant is optionally propelled by pump  120  or a thermosiphon through a another three-way valve  199  and returns to the secondary side of the subcooling heat exchanger  166  where subcooling is transferred to the primary side containing refrigerant leaving the air conditioner unit  102 . In this manner the system performs as a subcooled air conditioning system with much greater cooling capacity than the air conditioner unit alone. Whereas the aforementioned refrigerant loops have been described as having a particular direction, it is shown and contemplated that these loops (e.g. cooling circuit  108 ) may be run in either direction. 
         [0069]    The foregoing description of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and other modifications and variations may be possible in light of the above teachings. The embodiment was chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and various modifications as are suited to the particular use contemplated. It is intended that the appended claims be construed to include other alternative embodiments of the invention except insofar as limited by the prior art.