System and method for liquid-suction heat exchange thermal energy storage

Disclosed is a method and device for a thermal energy storage liquid-suction heat exchanger (TES-LSHX) for air conditioning and refrigeration (AC/R) applications. The disclosed embodiments allow energy to be stored and aggregated over one period of time, and dispatched at a later period of time, to improve AC/R system efficiency during desired conditions. Not only are the benefits of LSHX stored and aggregated for later use, but when dispatched, the discharge rate can exceed the charge rate thereby further enhancing the benefit of demand reduction to utilities. The disclosed embodiments allow great flexibility and can be incorporated into OEM AC/R system designs, and/or bundled with condensing units or evaporator coils. These TES-LSHX systems can be retrofit with existing systems by installing the product at any point along the existing AC/R system's line set.

BACKGROUND OF THE INVENTION

With the increasing demands on peak demand power consumption, Thermal Energy Storage (TES) 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.

SUMMARY OF THE INVENTION

An embodiment of the present invention may therefore comprise: an integrated refrigerant-based thermal energy storage and cooling system comprising: a condensing unit, the condensing unit comprising a compressor and a condenser; an expansion device connected downstream of the condensing unit; an evaporator connected downstream of the expansion device; a thermal energy storage module comprising: a thermal storage media contained therein; a liquid heat exchanger between the condenser and the expansion device, that facilitates heat transfer between a refrigerant and the thermal storage media; a suction heat exchanger between the evaporator and the compressor that facilitates heat transfer between the refrigerant and the thermal storage media; and, a first valve that facilitates flow of refrigerant from the condenser to the thermal energy storage module or the expansion device.

An embodiment of the present invention may also comprise: an integrated 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, an evaporator connected downstream of the expansion device; a thermal energy storage module comprising: a thermal storage media contained therein; a liquid heat exchanger; and, a suction heat exchanger; a thermal energy storage discharge loop comprising: an isolated liquid line heat exchanger in thermal communication with the liquid heat exchanger, the isolated liquid line heat exchanger in thermal communication with the refrigeration loop between the condenser and the expansion device, the discharge loop that facilitates heat transfer between the thermal storage media and the refrigerant; a first valve that facilitates thermal communication between the liquid heat exchanger and the isolated liquid line heat exchanger; a thermal energy storage suction loop comprising: an isolated suction line heat exchanger in thermal communication with the suction heat exchanger, the isolated suction line heat exchanger in thermal communication with the refrigeration loop between the evaporator and the condenser, the suction loop that facilitates heat transfer between the thermal storage media and the refrigerant; a second valve that facilitates thermal communication between the suction heat exchanger and the isolated liquid suction heat exchanger.

An embodiment of the present invention may therefore comprise: a method of providing cooling with a thermal energy storage and cooling system comprising: compressing and condensing a refrigerant with a compressor and a condenser to create a high-pressure refrigerant; during a first time period: expanding the high-pressure refrigerant with an expansion device to produce expanded refrigerant and provide load cooling with an evaporator; transferring cooling from the expanded refrigerant downstream of the evaporator to a thermal energy storage media within a thermal energy storage module via a suction heat exchanger constrained therein; and, returning the expanded refrigerant to the compressor; during a second time period: subcooling the high-pressure refrigerant downstream of the compressor with the thermal energy storage media within the thermal energy storage module via a liquid heat exchanger constrained therein; expanding the subcooled refrigerant with the expansion device to produce expanded refrigerant and provide load cooling with the evaporator; transferring cooling from the expanded refrigerant downstream of the evaporator to the thermal energy storage media via the suction heat exchanger; and, returning the expanded refrigerant to the compressor; during a third time period: subcooling the high-pressure refrigerant downstream of the compressor with the thermal energy storage media within the thermal energy storage module via the liquid heat exchanger; expanding the subcooled refrigerant with the expansion device to produce expanded refrigerant and provide load cooling with the evaporator; and, returning the expanded refrigerant to the compressor.

An embodiment of the present invention may therefore comprise: a method of providing cooling with a thermal energy storage and cooling system comprising: compressing and condensing a refrigerant with a compressor and a condenser to create a high-pressure refrigerant; during a first time period: expanding the high-pressure refrigerant with an expansion device to produce expanded refrigerant and provide load cooling with an evaporator; transferring cooling from the expanded refrigerant downstream of the evaporator to a thermal energy storage media within a thermal energy storage module via an isolated suction line heat exchanger; and, returning the expanded refrigerant to the compressor; during a second time period: subcooling the high-pressure refrigerant downstream of the condenser with the thermal energy storage media via an isolated liquid line heat exchanger; expanding the subcooled refrigerant with the expansion device to produce expanded refrigerant and provide load cooling with the evaporator; transferring cooling from the expanded refrigerant downstream of the evaporator to the thermal energy storage media via the isolated suction line heat exchanger; and, returning the expanded refrigerant to the compressor; during a third time period: subcooling the high-pressure refrigerant downstream of the condenser with the thermal energy storage media via an isolated liquid line heat exchanger; expanding the subcooled refrigerant with the expansion device to produce expanded refrigerant and provide load cooling with the evaporator; and, returning the expanded refrigerant to the compressor.

An embodiment of the present invention may also comprise: an integrated 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, an evaporator connected downstream of the expansion device; a thermal energy storage module comprising: a thermal storage and transfer media contained therein; a thermal energy storage discharge loop comprising: an isolated liquid line heat exchanger in thermal communication with the thermal energy storage module, the isolated liquid line heat exchanger in thermal communication with the refrigeration loop between the condenser and the expansion device, the discharge loop that facilitates heat transfer between the thermal storage and transfer media in the thermal energy storage module and the refrigerant; a first valve that facilitates thermal communication between the thermal energy storage module and the isolated liquid line heat exchanger; a thermal energy storage charge loop comprising: an isolated suction line heat exchanger in thermal communication with the thermal energy storage module, the isolated suction line heat exchanger in thermal communication with the refrigeration loop between the evaporator and the condenser, the charge loop that facilitates heat transfer between the thermal storage and transfer media in the thermal energy storage module and the refrigerant; a second valve that facilitates thermal communication between the thermal energy storage module and the isolated liquid suction heat exchanger.

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. 1illustrates an embodiment of a thermal energy storage liquid-suction heat exchanger (TES-LSHX) for air conditioning and refrigeration (AC/R) applications. As illustrated inFIG. 1, a variety of modes may be utilized in the system shown to provide cooling in various conventional or non-conventional air conditioning/refrigerant applications and utilized with an integrated condenser/compressor/evaporator (e.g., off-the-shelf unit or original equipment manufactured [OEM]) as either a retrofit to an existing system or a completely integrated new install. In this embodiment, three primary modes of operation are attainable with the system as shown: LSHX mode, charge mode, and discharge modes.

The TES-LSHX embodied inFIG. 1allows the benefits of liquid-suction heat exchangers that can be stored and aggregated over one period of time, and dispatched at a later period of time, to improve AC/R system efficiency during desired conditions. As an example, many TES-LSHX systems may be deployed in a geographic region and the aggregated performance improvements dispatched to reduce peak utility system demand. Not only are the benefits of LSHX stored and aggregated for later use, but when dispatched, the discharge rate can exceed the charge rate, thereby further enhancing the benefit of demand reduction to utilities. The disclosed embodiments allow great flexibility and can be incorporated into OEM AC/R system designs, and/or bundled with condensing units or evaporator coils. These TES-LSHX systems can be retrofit with existing systems by installing the product at any point along the existing AC/R system's lineset.

FIG. 1shows a single valve design for a direct heat exchange configuration. The direct heat exchange configuration refers to the fact that energy is transferred directly from the AC/R system's liquid and suction lines to the storage media or each other. For example, the refrigerant used in the AC/R system to provide cooling to the load, is in direct thermal communication with the storage media. The single valve design shown inFIG. 1allows several modes of operation including LSHX, charge, and discharge. The multi-valve design shown inFIG. 2, allows additional modes of operation, including LSHX isolated (normal direct expansion AC/R operation) and subcooling only discharge.

When operating in charge mode, the system ofFIG. 1activates all basic AC/R components, including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In addition, the TES-LSHX116rejects heat from the storage media160to the cold vapor return line between the evaporator and compressor. Valve V1122directs warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, to the expansion device120, bypassing the TES-LSHX116. The warm liquid is expanded by the evaporator expansion device120to generate a cold mixed phase refrigerant that absorbs heat and is vaporized in the evaporator114to provide cooling. The cold vapor refrigerant leaves the evaporator114and enters the TES-LSHX116where it transfers cooling to (absorbs heat from) the storage media160through the suction heat exchanger170, resulting in increased superheat of the cold vapor refrigerant prior to entering the compressor110. In this mode, there is a net energy removal from the storage media160.

In the LSHX mode of the system ofFIG. 1, all basic AC/R components are active including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In this embodiment, the TES-LSHX116transfers energy from the warm liquid supply line to the cold vapor suction line through direct heat exchange in the liquid heat exchanger175and/or via the storage media160. Valve V1122in this example, directs warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, to the TES-LSHX116(storage module) where it rejects heat to the storage media160and/or the cold vapor refrigerant leaving the evaporator114via the suction heat exchanger170. This rejection of heat to the storage media160, results in increased subcooling of the warm liquid prior to entering the evaporator expansion device120. The warm liquid is expanded by the evaporator expansion device120to generate a cold mixed phase refrigerant that absorbs heat and is vaporized in the evaporator114to provide cooling. The cold vapor refrigerant leaves the evaporator114and enters the TES-LSHX116where it transfers cooling to (absorbs heat from) the storage media160and/or the warm liquid refrigerant leaving valve V1122via the liquid heat exchanger175. This results in increased superheating of the cold vapor refrigerant prior to entering the compressor110. In this mode, the TES-LSHX116acts as a traditional LSHX (i.e., there is zero or a neutral net energy transfer to the storage media160).

In the discharge mode of the system ofFIG. 1, all basic AC/R components are active including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In addition, the TES-LSHX116(storage module) transfers energy from the warm liquid supply line to the storage media160and the cold vapor suction line through direct heat exchange in the LSHX175. In this mode, valve V1122directs warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, to the TES-LSHX116, where it rejects heat to the storage media160and/or the cold vapor refrigerant leaving the evaporator114via the suction heat exchanger170. This results in increased subcooling of the warm liquid prior to entering the evaporator expansion device120. This warm liquid is expanded by the evaporator expansion device120to generate a cold mixed phase refrigerant that absorbs heat and is vaporized in the evaporator114to provide cooling. The cold vapor refrigerant leaves the evaporator114and enters the TES-LSHX116where it transfers cooling to (absorbs heat from) the storage media160and/or the warm liquid refrigerant leaving valve V1122via the suction heat exchanger170, resulting in increased superheat of the cold vapor refrigerant prior to entering the compressor110. In this mode, there is a net energy addition to the storage media160.

FIG. 2illustrates another embodiment of a TES-LSHX for AC/R applications. As illustrated inFIG. 2, the addition of a second valve V2124provides additional modes that may be utilized in the system as shown, to provide cooling in various conventional or non-conventional AC/R applications and utilized with an integrated condenser/compressor/evaporator as either a retrofit to an existing system or a completely integrated new install. In this embodiment, five primary modes of operation are attainable with the system as shown: LSHX mode, charge mode, discharge mode, LSHX isolated mode and subcooling only discharge mode.

In charge mode of the system ofFIG. 2, all basic AC/R components are active including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In addition, the TES-LSHX116rejects heat from the storage media160to the cold vapor return line. Valve V1122directs warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, to the evaporator expansion device120, bypassing the TES-LSHX116. The warm liquid is expanded by the evaporator expansion device120to generate a cold mixed phase refrigerant that absorbs heat and is vaporized in the evaporator114to provide cooling. The cold vapor refrigerant leaves the evaporator114and is directed by valve V2124to the TES-LSHX116where it transfers cooling to (absorbs heat from) the storage media160via the suction heat exchanger170, resulting in increased superheat of the cold vapor refrigerant prior to entering the compressor110. In this mode, there is a net energy removal from the storage media160.

The system ofFIG. 2, when in LSHX mode, operates with all basic AC/R components active, including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In addition, the TES-LSHX116transfers energy from the warm liquid supply line to the cold vapor suction line through direct heat exchange in the liquid heat exchanger175and/or via the storage media160. Valve V1122directs warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, to the TES-LSHX116(storage module). Here, the refrigerant rejects heat to the storage media160and/or the cold vapor refrigerant leaving the evaporator114via the liquid heat exchanger175, resulting in increased subcooling of the warm liquid prior to entering the evaporator expansion device120. The warm liquid is expanded by the evaporator expansion device120to generate a cold mixed phase refrigerant that absorbs heat and is vaporized in the evaporator114to provide cooling. The cold vapor refrigerant leaves the evaporator114and is directed by valve V2124to the TES-LSHX116where it transfers cooling to (absorbs heat from) the storage media160and/or the warm liquid refrigerant leaving valve V1122via the suction heat exchanger170. This results in increased superheat of the cold vapor refrigerant prior to entering the compressor110. In this mode, the TES-LSHX116is in a discharged state and acts as a traditional LSHX (i.e., there is zero or a neutral net energy transfer to the storage media160).

In discharge mode of the system ofFIG. 2, all basic AC/R components are active including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In addition, the TES-LSHX116transfers energy from the warm liquid supply line to the storage media160and the cold vapor suction line through direct heat exchange in the liquid heat exchanger175. Valve V1122directs warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, to the TES-LSHX116where it rejects heat to the storage media160and/or the cold vapor refrigerant leaving the evaporator114via the liquid heat exchanger175. This results in increased subcooling of the warm liquid prior to entering the evaporator expansion device120. The warm liquid is expanded by the evaporator expansion device120to generate a cold mixed phase refrigerant that absorbs heat and is vaporized in the evaporator114to provide cooling. The cold vapor refrigerant leaves the evaporator114and is directed by valve V2124to the TES-LSHX116where it transfers cooling to (absorbs heat from) the storage media160and/or the warm liquid refrigerant leaving valve V1122via the suction heat exchanger170. This results in increased superheat of the cold vapor refrigerant prior to entering the compressor110. In this mode, there is a net energy addition to the storage media160.

In LSHX isolated mode, all basic AC/R components of the system ofFIG. 2are active, including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. The TES-LSHX116is isolated from the AC/R circuit and is inactive. Valve V1122directs warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, to the evaporator expansion device120, bypassing the TES-LSHX116. The warm liquid is expanded by the evaporator expansion device120to generate a cold mixed phase refrigerant that absorbs heat and is vaporized in the evaporator114to provide cooling. The cold vapor refrigerant leaves the evaporator114and is directed by valve V2124to the compressor110, bypassing the TES-LSHX116. In this mode, the TES-LSHX116is isolated from the AC/R circuit and inactive, allowing the AC/R system to operate traditionally (no TES-LSHX or LSHX operation) if desired.

In subcooling only discharge mode, all basic AC/R components of the system ofFIG. 2are active, including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In addition, the TES-LSHX116transfers energy from the warm liquid supply line to the storage media160. Valve V1122directs warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, to the TES-LSHX116where it rejects heat to the storage media160via liquid heat exchanger175, resulting in increased subcooling of the warm liquid prior to entering the evaporator expansion device120. The warm liquid is expanded by the evaporator expansion device120to generate a cold mixed-phase refrigerant that transfers cooling (absorbs heat) and is vaporized in the evaporator114to provide cooling. The cold vapor refrigerant leaves the evaporator114and is directed by valve V2124to the compressor110, bypassing the TES-LSHX116. In this mode, there is a net energy addition to the storage media160.

FIG. 3illustrates yet another embodiment of a TES-LSHX for AC/R applications. As illustrated inFIG. 3, the addition of isolation to the TES-LSHX affords additional versatility and provides additional modes that may be utilized in the system as shown, to provide cooling in various conventional or non-conventional AC/R applications and utilized with an integrated condenser/compressor/evaporator as either a retrofit to an existing system or a completely integrated new install. In this embodiment, five primary modes of operation are attainable with the system as shown: LSHX mode, charge mode, discharge mode, LSHX isolated mode and subcooling only discharge mode.

In charge mode of the system ofFIG. 3, all basic AC/R components are active including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In addition, the TES-LSHX116(storage module) rejects heat from the storage media160to the cold vapor return line through an isolated circuit. The heat exchange process that occurs in the isolating suction line heat exchanger140between the AC/R circuit refrigerant and the suction line secondary circuit refrigerant, results in increased superheat in the cold vapor refrigerant leaving the evaporator114prior to entering the compressor110. Valve V1122is in a “closed” state preventing cold liquid refrigerant from flowing from the TES-LSHX116to the isolating liquid line heat exchanger138. Cold vapor refrigerant in the isolating suction line heat exchanger140, rejects heat to the cold vapor leaving the evaporator114and condenses. The cold liquid refrigerant in the isolating suction line heat exchanger140flows to the TES-LSHX116via refrigerant pump104and valve V2124, which is in the “open” state, where it absorbs heat from the storage media160via the suction heat exchanger170and vaporizes. The vapor generated in the suction heat exchanger170flows back to the isolating suction line heat exchanger140to repeat the process. In the charge mode, there is a net energy removal from the storage media160. The refrigerant pumps102,104in this configuration are optional. An alternative motive force for secondary circuit refrigerant movement is a gravity assisted thermosiphon. Valve V2124is also optional in this configuration.

The system ofFIG. 3, when in LSHX mode, operates with all basic AC/R components active, including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In addition, the TES-LSHX116transfers energy from the warm liquid supply line of the AC/R circuit to the cold vapor suction line of the AC/R circuit through multiple isolated circuits. The heat exchange processes that occur in the isolating heat exchangers138and140, between the AC/R circuit refrigerant, the liquid line secondary circuit refrigerant, and the suction line secondary circuit refrigerant, result in increased subcooling of the warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, prior to entering the evaporator expansion device120. This also results in an increased superheat in the cold vapor refrigerant leaving the evaporator114prior to entering the compressor110. Valve V1122is in an “open” state allowing cold liquid refrigerant to flow from the TES-LSHX116to the isolating liquid line heat exchanger138, via refrigerant pump102. The liquid refrigerant in the secondary circuit absorbs heat from the warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, via the isolating liquid line heat exchanger138, and vaporizes.

The cold vapor refrigerant in the liquid line secondary circuit leaves the isolating liquid line heat exchanger138and returns to the TES-LSHX116, where it rejects heat to the storage media160and/or the cold liquid refrigerant in the suction line secondary circuit via the liquid heat exchanger175, and condenses. Cold vapor refrigerant in the suction line secondary circuit of the suction heat exchanger170leaves the TES-LSHX116and enters the isolating suction line heat exchanger140. Here, heat is rejected to the cold vapor refrigerant leaving the evaporator114via the isolating suction line heat exchanger140, and condenses. The cold liquid refrigerant in the isolating suction line heat exchanger140returns to the TES-LSHX116via refrigerant pump104and valve V2124, which is in the “open” state, where the refrigerant transfers cooling to (absorbs heat from) the storage media160and/or the vapor refrigerant in the liquid line secondary circuit via the suction heat exchanger170, and vaporizes. In this mode, the TES-LSHX116acts as a traditional LSHX. In this mode, there is zero or a neutral net energy transfer to the storage media160. The refrigerant pumps102,104in this configuration are also optional, with alternative motive force being gravity assisted thermosiphon. Valve V2124is also optional in this configuration.

The system ofFIG. 3, when in discharge mode, operates with all basic AC/R components active, including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In addition, the TES-LSHX116transfers energy from the warm liquid supply line of the AC/R circuit to the storage media160, and the cold vapor suction line of the AC/R circuit through multiple isolated circuits. The heat exchange processes that occur in the isolating heat exchangers138and140, between the AC/R circuit refrigerant, the liquid line secondary circuit refrigerant, and the suction line secondary circuit refrigerant, result in increased subcooling of the warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, prior to entering the evaporator expansion device120, and increased superheat in the cold vapor refrigerant leaving the evaporator114, prior to entering the compressor110. Valve V1122is in an “open” state allowing cold liquid refrigerant to flow from the TES-LSHX116to the isolating liquid line heat exchanger138, via refrigerant pump102.

The liquid refrigerant in the secondary circuit, transfers cooling to (absorbs heat from) the warm liquid refrigerant leaving the condenser112via the isolating liquid line heat exchanger138, and vaporizes. The cold vapor refrigerant in the liquid line secondary circuit, leaves the isolating liquid line heat exchanger138, and returns to the TES-LSHX116. Here, the refrigerant rejects heat to the storage media160and/or the cold liquid refrigerant in the suction line secondary circuit via the liquid heat exchanger175, and condenses. Cold vapor refrigerant in the suction line secondary circuit of the suction heat exchanger170, leaves the TES-LSHX116and enters the isolating suction line heat exchanger140. Here, the refrigerant rejects heat to the cold vapor refrigerant leaving the evaporator114, via the isolating suction line heat exchanger140, and condenses. The cold liquid refrigerant in the isolating suction line heat exchanger140, returns to the TES-LSHX116via refrigerant pump104and valve V2124(which is in the “open” state) where it transfers cooling to (absorbs heat from) the storage media160, and/or the vapor refrigerant in the liquid line secondary circuit via the suction heat exchanger170, and vaporizes. In this mode, there is a net energy addition to the storage media160. The refrigerant pumps102,104in this configuration once again are optional, as is valve V2124.

In LSHX isolated mode, all basic AC/R components of the system ofFIG. 3are active, including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In this mode, the TES-LSHX116is inactive, valve V1122is in a “closed” state, and refrigerant pump102is inactive. This prevents liquid refrigerant from leaving the TES-LSHX116and absorbing heat from the warm liquid refrigerant leaving the condenser112via the isolating liquid line heat exchanger138. Valve V2124is in a “closed” state, and refrigerant pump104is inactive. This prevents cold liquid refrigerant in the isolating suction line heat exchanger140from returning to the TES-LSHX116, and absorbing heat from the storage media160, via the suction heat exchanger170. In this mode, the TES-LSHX116is inactive, allowing the AC/R system to operate traditionally (no TES-LSHX or LSHX operation). The refrigerant pumps in this configuration once again are optional.

In subcooling only discharge mode, all basic AC/R components of the system ofFIG. 3are active, including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In addition, the TES-LSHX116transfers energy from the warm liquid supply line, to the storage media160, through an isolated circuit. The heat exchange process that occurs in the isolating liquid line heat exchanger138, between the AC/R circuit refrigerant and the liquid line secondary circuit refrigerant, results in increased subcooling of the warm liquid refrigerant leaving the condenser112prior to entering the evaporator expansion device120. Valve V1122is in an “open” state, which allows cold liquid refrigerant to flow from the TES-LSHX116, to the isolating liquid line heat exchanger138, via refrigerant pump102. The liquid refrigerant in the secondary circuit, absorbs heat from the warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, via the isolating liquid line heat exchanger138, and vaporizes. The cold vapor refrigerant in the liquid line secondary circuit leaves the isolating liquid line heat exchanger138, and returns to the TES-LSHX116. Here, the refrigerant rejects heat to the storage media160via the liquid heat exchanger175, and condenses. Valve V2124is in a “closed” state, and refrigerant pump104is inactive, thereby preventing cold liquid refrigerant in the isolating suction line heat exchanger140from returning to the TES-LSHX116, and absorbing heat from the storage media160via, the suction heat exchanger170. In this mode, there is a net energy addition to the storage media160. The refrigerant pumps102,104in this configuration once again are optional.

FIG. 4illustrates yet another embodiment of a TES-LSHX for AC/R applications. As illustrated inFIG. 4, the addition of isolation to the TES-LSHX affords additional versatility and provides additional modes that may be utilized in the system as shown, to provide cooling in various conventional or non-conventional AC/R applications and utilized with an integrated condenser/compressor/evaporator as either a retrofit to an existing system or a completely integrated new install. In this embodiment the TES-LSHX utilizes a storage/heat transfer media162that acts to store thermal capacity as well as transport this capacity (heating and/or cooling) to the primary AC/R circuit. This storage/heat transfer media162may be brine, glycol, ice slurry, encapsulated storage with liquid, or any other type or combination that facilitates storage and transport of thermal energy. Five primary modes of operation are attainable with the system as shown: LSHX mode, charge mode, discharge mode, LSHX isolated mode and subcooling only discharge mode.

In charge mode of the system ofFIG. 4, all basic AC/R components are active including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In addition, the TES-LSHX116(storage module) rejects heat from the storage/heat transfer media162to the cold vapor return line by directly circulating the storage media through the isolating heat exchanger in communication with the refrigerant loop. The heat exchange process that occurs in the isolating suction line heat exchanger140between the AC/R circuit refrigerant and the suction line secondary circuit, results in increased superheat in the cold vapor refrigerant leaving the evaporator114prior to entering the compressor110.

Valve V1122is in a “closed” state preventing storage/heat transfer media162from flowing from the TES-LSHX116to the isolating liquid line heat exchanger138. Cold storage/heat transfer media162in the isolating suction line heat exchanger140rejects heat to the cold vapor leaving the evaporator114. The cold storage/heat transfer media162in the isolating suction line heat exchanger140flows to the TES-LSHX116via pump105and valve V2124, which is in the “open” state, where it absorbs heat from additional storage/heat transfer media162. The storage/heat transfer media162flows back to the isolating suction line heat exchanger140to repeat the process. In the charge mode, there is a net energy removal from the storage/heat transfer media162. The pumps103,105in this configuration are optional. An alternative motive force for secondary circuit media movement is a gravity assisted thermosiphon. Valve V2124is also optional in this configuration.

The system ofFIG. 4, when in LSHX mode, operates with all basic AC/R components active, including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In addition, the TES-LSHX116transfers energy from the warm liquid supply line of the AC/R circuit to the cold vapor suction line of the AC/R circuit through an isolated circuit. The heat exchange processes that occur in the isolating heat exchangers138and140, between the AC/R circuit refrigerant, the liquid line secondary circuit media, and the suction line secondary circuit media, result in increased subcooling of the warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, prior to entering the evaporator expansion device120. This also results in an increased superheat in the cold vapor refrigerant leaving the evaporator114prior to entering the compressor110. Valve V1122is in an “open” state allowing cold storage/heat transfer media162to flow from the TES-LSHX116to the isolating liquid line heat exchanger138, via pump103. The media in the secondary circuit absorbs heat from the warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, via the isolating liquid line heat exchanger138.

The warm storage/heat transfer media162in the liquid line secondary circuit leaves the isolating liquid line heat exchanger138and returns to the TES-LSHX116, and/or the storage/heat transfer media162in the suction line secondary circuit. Warm storage/heat transfer media162in the suction line secondary circuit leaves the TES-LSHX116and enters the isolating suction line heat exchanger140. Here, heat is rejected to the cold vapor refrigerant leaving the evaporator114via the isolating suction line heat exchanger140. The cold storage/heat transfer media162in the isolating suction line heat exchanger140returns to the TES-LSHX116and/or the storage/heat transfer media162in the liquid line secondary circuit via pump105and valve V2124, which is in the “open” state. In this mode, the TES-LSHX116acts as a traditional LSHX. In this mode, there is zero or a neutral net energy transfer to the storage/heat transfer media162. The pumps103,105in this configuration are also optional, with alternative motive force being gravity assisted thermosiphon. Valve V2124is also optional in this configuration.

The system ofFIG. 4, when in discharge mode, operates with all basic AC/R components active, including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In addition, the TES-LSHX116transfers energy from the warm liquid supply line of the AC/R circuit to the storage/heat transfer media162, and the cold vapor suction line of the AC/R circuit through an isolated circuit. The heat exchange processes that occur in the isolating heat exchangers138and140, between the AC/R circuit refrigerant, the liquid line secondary circuit, and the suction line secondary circuit, result in increased subcooling of the warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, prior to entering the evaporator expansion device120, and increased superheat in the cold vapor refrigerant leaving the evaporator114, prior to entering the compressor110. Valve V1122is in an “open” state allowing cold storage/heat transfer media162to flow from the TES-LSHX116to the isolating liquid line heat exchanger138, via pump103.

The storage/heat transfer media162in the secondary circuit, transfers cooling to (absorbs heat from) the warm liquid refrigerant leaving the condenser112via the isolating liquid line heat exchanger138. The warm storage/heat transfer media162in the liquid line secondary circuit, leaves the isolating liquid line heat exchanger138, and returns to the TES-LSHX116. Warm storage/heat transfer media162in the TES-LSHX116then enters the isolating suction line heat exchanger140. Here, the media rejects heat to the cold vapor refrigerant leaving the evaporator114via the isolating suction line heat exchanger140. The cold storage/heat transfer media162in the isolating suction line heat exchanger140, returns to the TES-LSHX116via pump105and valve V2124(which is in the “open” state) where it transfers cooling to the remaining storage/heat transfer media162, and/or the media in the liquid line secondary circuit. In this mode, there is a net energy addition to the storage/heat transfer media162. The pumps103,105in this configuration once again are optional, as is valve V2124.

In LSHX isolated mode, all basic AC/R components of the system ofFIG. 4are active, including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In this mode, the TES-LSHX116is inactive, valve V1122is in a “closed” state, and pump103is inactive. This prevents storage/heat transfer media162from leaving the TES-LSHX116and absorbing heat from the warm liquid refrigerant leaving the condenser112via the isolating liquid line heat exchanger138. Valve V2124is in a “closed” state, and pump105is inactive. This prevents cold storage/heat transfer media162in the isolating suction line heat exchanger140from returning to the TES-LSHX116. In this mode, the TES-LSHX116is inactive, allowing the AC/R system to operate traditionally (no TES-LSHX or LSHX operation). The pumps in this configuration once again are optional.

In subcooling only discharge mode, all basic AC/R components of the system ofFIG. 4are active, including the compressor110, condenser112, evaporator expansion device120, and the evaporator114. In addition, the TES-LSHX116transfers energy from the warm liquid supply line, to the storage/heat transfer media162, through an isolated circuit. The heat exchange process that occurs in the isolating liquid line heat exchanger138between the AC/R circuit refrigerant and the liquid line secondary circuit media, results in increased subcooling of the warm liquid refrigerant leaving the condenser112prior to entering the evaporator expansion device120. Valve V1122is in an “open” state, which allows cold storage/heat transfer media162to flow from the TES-LSHX116, to the isolating liquid line heat exchanger138, via pump103. The media in the secondary circuit absorbs heat from the warm liquid refrigerant leaving the condenser112, after being compressed by the compressor110, via the isolating liquid line heat exchanger138. The warm storage/heat transfer media162in the liquid line secondary circuit leaves the isolating liquid line heat exchanger138, and returns to the TES-LSHX116. Here, the media rejects heat to the remaining storage/heat transfer media162. Valve V2124is in a “closed” state, and pump105is inactive, thereby preventing cold storage/heat transfer media162in the isolating suction line heat exchanger140from returning to the TES-LSHX116. In this mode, there is a net energy addition to the storage/heat transfer media162. The pumps103,105in this configuration once again are optional.

The disclosed system may utilize a relatively small capacity condenser compressor (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. Whereas the aforementioned refrigerant loops have been described as having a particular direction, it is shown and contemplated that these loops may be run in either direction whenever possible. Additionally, it is contemplated that the isolated loops for the suction line heat exchanger and the liquid line heat exchanger in the embodiment ofFIG. 3may be refrigerant based or coolant based as inFIG. 4. That is, each of the loops may be phase change refrigerant such as R-22, R-410A, Butane or the like, or they may be non-phase change material such as brine, ice slurry, glycol or the like.