THERMAL ENERGY STORAGE AND COOLING SYSTEM WITH ISOLATED EVAPORATOR COIL

- Ice Energy, Inc.

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.

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Description
CROSS REFERENCE TO RELATED APPLICATION

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

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

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.

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.

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.

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.

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.

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

In the drawings,

FIG. 1 illustrates an embodiment of a thermal energy storage and cooling system with an isolated evaporator coil in a secondary cooling loop.

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.

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.

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.

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.

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.

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

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

In ice-melt mode, the system operates substantially similar to the embodiment described in FIG. 1.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

Claims

1. A refrigerant-based thermal energy storage and cooling system comprising:

a refrigerant loop containing a refrigerant comprising: a condensing unit, said condensing unit comprising a compressor and a condenser; an expansion device connected downstream of said condensing unit; and, a primary heat exchanger connected between said expansion device and said condensing unit that is located within a tank filled with a fluid capable of a phase change between liquid and solid, said primary heat exchanger that performs as an evaporator and facilitates heat transfer from said refrigerant from said condenser to cool said fluid and to freeze at least a portion of said fluid within said tank in a first time period, and said primary heat exchanger that performs as a condenser and facilitates heat transfer from said fluid to cool said 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 said refrigerant condensed within said primary heat exchanger and said heat transfer medium, said heat transfer medium that transfers cooling from said first isolating heat exchanger to said load heat exchanger in said second time period; and, a second isolating heat exchanger that facilitates thermal contact between said refrigerant condensed within said condensing unit and said heat transfer medium, said heat transfer medium that transfers cooling from said second isolating heat exchanger to said load heat exchanger in a third time period.

2. The system of claim 1 further comprising:

a refrigerant management vessel in fluid communication with, and located between said condensing unit and said primary heat exchanger comprising: an inlet connection that receives said refrigerant from said condensing unit and said primary heat exchanger; a first outlet connection that supplies said refrigerant to said primary heat exchanger; and, a second outlet connection that supplies said refrigerant to said condensing unit.

3. The system of claim 1 wherein said expansion device is chosen from the group consisting of a thermal expansion valve, an electronic expansion valve and a mixed-phase regulator.

4. The system of claim 1 wherein said fluid is a eutectic material.

5. The system of claim 1 wherein said fluid is water.

6. The system of claim 1 wherein said load heat exchanger is at least one mini-split evaporator.

7. The system of claim 1 wherein said second time period is concurrent with said third time period.

8. The system of claim 1 wherein said heat transfer medium is a coolant.

9. The system of claim 1 wherein said heat transfer medium is a refrigerant.

10. The system of claim 1 further comprising:

a subcooling heat exchanger that facilitates thermal contact between said heat transfer medium upstream of said load heat exchanger and said refrigerant exiting said condenser to subcool said refrigerant.

11. The system of claim 1 further comprising:

a bypass refrigeration loop that transfers cooling from said refrigerant leaving said expansion device to said load heat exchanger and returns warm expanded said refrigerant to said compressor.

12. A refrigerant-based thermal energy storage and cooling system comprising:

a refrigerant loop containing a refrigerant comprising: a condensing unit, said condensing unit comprising a compressor and a condenser; an expansion device connected downstream of said condensing unit; and, a primary heat exchanger connected between said expansion device and said condensing unit that is located within a tank filled with a fluid capable of a phase change between liquid and solid, said primary heat exchanger that performs as an evaporator and facilitates heat transfer from said refrigerant from said condenser to cool said fluid and to freeze at least a portion of said fluid within said 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 said fluid and said heat transfer medium, said heat transfer medium that transfers cooling from said first isolating heat exchanger to said load heat exchanger in said second time period; and, a second isolating heat exchanger that facilitates thermal contact between said refrigerant condensed within said condensing unit and said heat transfer medium, said heat transfer medium that transfers cooling from said second isolating heat exchanger to said load heat exchanger in a third time period.

13. The system of claim 12 further comprising:

a refrigerant management vessel in fluid communication with, and located between said condensing unit and said primary heat exchanger comprising:
an inlet connection that receives said refrigerant from said condensing unit and said primary heat exchanger;
a first outlet connection that supplies said refrigerant to said primary heat exchanger; and,
a second outlet connection that supplies said refrigerant to said condensing unit.

14. The system of claim 12 wherein said expansion device is chosen from the group consisting of a thermal expansion valve, an electronic expansion valve and a mixed-phase regulator.

15. The system of claim 12 wherein said fluid is a eutectic material.

16. The system of claim 12 wherein said fluid is water.

17. The system of claim 12 wherein said load heat exchanger is at least one mini-split evaporator.

18. The system of claim 12 wherein said second time period is concurrent with said third time period.

19. The system of claim 12 wherein said heat transfer medium is a coolant.

20. The system of claim 12 wherein said heat transfer medium is a refrigerant.

21. The system of claim 12 further comprising:

a subcooling heat exchanger that facilitates thermal contact between said heat transfer medium upstream of said load heat exchanger and said refrigerant exiting said condenser to subcool said refrigerant.

22. The system of claim 12 further comprising:

a bypass refrigeration loop that transfers cooling from said refrigerant leaving said expansion device to said load heat exchanger and returns warm expanded said refrigerant to said compressor.

23. A refrigerant-based thermal energy storage and cooling system comprising:

a refrigerant loop containing a refrigerant comprising: a condensing unit, said condensing unit comprising a compressor and a condenser; an expansion device connected downstream of said condensing unit; and, a primary heat exchanger connected between said expansion device and said condensing unit that is located within a tank filled with a fluid capable of a phase change between liquid and solid, said primary heat exchanger that performs as an evaporator and facilitates heat transfer from said refrigerant from said condenser to cool said fluid and to freeze at least a portion of said fluid within said tank in a first time period, and said primary heat exchanger that performs as a condenser and facilitates heat transfer from said fluid to cool said 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 said fluid and said heat transfer medium, said heat transfer medium that transfers cooling from said first isolating heat exchanger to said load heat exchanger in said second time period; and, a second isolating heat exchanger that facilitates thermal contact between said refrigerant cooled by said fluid within said tank and said heat transfer medium, said heat transfer medium that transfers cooling from said second isolating heat exchanger to said load heat exchanger in a third time period.

24. The system of claim 23 further comprising:

a refrigerant management vessel in fluid communication with, and located between said condensing unit and said primary heat exchanger comprising:
an inlet connection that receives said refrigerant from said condensing unit and said primary heat exchanger;
a first outlet connection that supplies said refrigerant to said primary heat exchanger; and,
a second outlet connection that supplies said refrigerant to said condensing unit.

25. The system of claim 23 wherein said expansion device is chosen from the group consisting of a thermal expansion valve, an electronic expansion valve and a mixed-phase regulator.

26. The system of claim 23 wherein said fluid is a eutectic material.

27. The system of claim 23 wherein said fluid is water.

28. The system of claim 23 wherein said load heat exchanger is at least one mini-split evaporator.

29. The system of claim 23 wherein said second time period is concurrent with said third time period.

30. The system of claim 23 wherein said heat transfer medium is a coolant.

31. The system of claim 23 wherein said heat transfer medium is a refrigerant.

32. The system of claim 23 further comprising:

a subcooling heat exchanger that facilitates thermal contact between said heat transfer medium upstream of said load heat exchanger and said refrigerant exiting said condenser to subcool said refrigerant.

33. The system of claim 23 further comprising:

a bypass refrigeration loop that transfers cooling from said refrigerant leaving said expansion device to said load heat exchanger and returns warm expanded said refrigerant to said compressor.

34. 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 said high-pressure refrigerant to provide cooling in a primary heat exchanger, said 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 said fluid and forming ice and cooled fluid within said tank;
during a second time period: transferring cooling from said fluid and said ice to said refrigerant within said primary heat exchanger; transferring cooling from said refrigerant cooled within said primary heat exchanger to a heat transfer medium in a cooling loop with a first isolating heat exchanger; and, transferring cooling from said heat transfer medium to a load heat exchanger within said cooling loop to provide load cooling;
during a third time period: transferring cooling from said refrigerant from said air conditioner unit to said heat transfer medium in said cooling loop with a second isolating heat exchanger; and, transferring cooling from said heat transfer medium to said load heat exchanger within said cooling loop to provide load cooling.

35. The method of claim 34 further comprising the step of:

managing volumes and phase of said refrigerant with a refrigerant management vessel, said refrigerant management vessel in fluid communication with said air conditioner unit and said primary heat exchanger.

36. The method of claim 34 wherein said steps of said second time period are performed concurrent with said steps of said third time period.

37. The method of claim 34 further comprising the step of:

expanding said heat transfer medium upstream of said load heat exchanger and condensing said heat transfer medium in said first isolating heat exchanger or in said second isolating heat exchanger.

38. The method of claim 34 further comprising the step of:

subcooling said refrigerant that exits said air conditioner unit with a subcooling heat exchanger in thermal communication with said heat transfer medium.

39. The method of claim 34 further comprising the steps of:

during a fourth time period: bypassing said primary heat exchanger with said refrigerant leaving said expansion device; and, transferring cooling from said refrigerant leaving said expansion device to said load heat exchanger to provide direct load cooling; returning warm expanded said refrigerant to said air conditioner unit.

40. 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 said high-pressure refrigerant to provide cooling in a primary heat exchanger, said 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 said fluid and forming ice and cooled fluid within said tank;
during a second time period: transferring cooling from said fluid to a heat transfer medium in a cooling loop with a first isolating heat exchanger; and, transferring cooling from said heat transfer medium to a load heat exchanger within said cooling loop to provide load cooling;
during a third time period; transferring cooling from said refrigerant from said air conditioner unit to said heat transfer medium in said cooling loop with a second isolating heat exchanger; and, transferring cooling from said heat transfer medium to said load heat exchanger within said cooling loop to provide load cooling.

41. The method of claim 40 further comprising the step of:

managing volumes and phase of said refrigerant with a refrigerant management vessel, said refrigerant management vessel in fluid communication with said air conditioner unit and said primary heat exchanger.

42. The method of claim 40 wherein said steps of said second time period are performed concurrent with said steps of said third time period.

43. The method of claim 40 further comprising the step of:

expanding said heat transfer medium upstream of said load heat exchanger and condensing said heat transfer medium in said first isolating heat exchanger or in said second isolating heat exchanger.

44. The method of claim 40 further comprising the step of:

subcooling said refrigerant that exits said air conditioner unit with a subcooling heat exchanger in thermal communication with said heat transfer medium.

45. The method of claim 40 further comprising the steps of:

during a fourth time period: bypassing said primary heat exchanger with said refrigerant leaving said expansion device; transferring cooling from said refrigerant leaving said expansion device to said load heat exchanger to provide direct load cooling; and, returning warm expanded said refrigerant to said air conditioner unit.

46. 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 said high-pressure refrigerant to provide cooling in a primary heat exchanger, said 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 said fluid and forming ice and cooled fluid within said tank; during a second time period: transferring cooling from said fluid to a heat transfer medium in a cooling loop with a first isolating heat exchanger, and transferring cooling from said heat transfer medium to a load heat exchanger within said cooling loop to provide load cooling;
during a third time period: transferring cooling from said fluid and said ice to said refrigerant within said primary heat exchanger; transferring cooling from said refrigerant cooled within said primary heat exchanger to said heat transfer medium in a cooling loop with a second isolating heat exchanger; and, transferring cooling from said heat transfer medium to said load heat exchanger within said cooling loop to provide load cooling.

47. The method of claim 56 further comprising the step of:

managing volumes and phase of said refrigerant with a refrigerant management vessel, said refrigerant management vessel in fluid communication with said air conditioner unit and said primary heat exchanger.

48. The method of claim 56 wherein said steps of said second time period are performed concurrent with said steps of said third time period.

49. The method of claim 56 further comprising the step of:

expanding said heat transfer medium upstream of said load heat exchanger and condensing said heat transfer medium in said first isolating heat exchanger or in said second isolating heat exchanger.

50. The method of claim 56 further comprising the step of:

subcooling said refrigerant that exits said air conditioner unit with a subcooling heat exchanger in thermal communication with said heat transfer medium.

51. The method of claim 56 further comprising the steps of:

during a fourth time period: bypassing said primary heat exchanger with said refrigerant leaving said expansion device; transferring cooling from said refrigerant leaving said expansion device to said load heat exchanger to provide direct load cooling; and, returning warm expanded said refrigerant to said air conditioner unit.
Patent History
Publication number: 20090293507
Type: Application
Filed: May 28, 2009
Publication Date: Dec 3, 2009
Applicant: Ice Energy, Inc. (Windsor, CO)
Inventors: Ramachandran Narayanamurthy (Loveland, CO), Brian Parsonnet (Fort Collins, CO), Donald Thomas Cook (Berthoud, CO)
Application Number: 12/473,499
Classifications
Current U.S. Class: Accumulating Holdover Ice In Situ (62/59); Heat Exchange Between Diverse Function Elements (62/513); Flow Line Connected Transfer Fluid Supply And Heat Exchanger (62/434); Condensed Liquid Receiver, E.g., Surge Tank (62/509)
International Classification: F25D 3/00 (20060101); F25B 41/00 (20060101); F25D 17/02 (20060101); F25B 39/04 (20060101);