REFRIGERANT CIRCUIT WITH INTEGRATED MULTI-MODE THERMAL ENERGY STORAGE

Abstract

Disclosed is a method and device for a refrigerant-based thermal energy storage and cooling system with integrated multi-mode refrigerant loops. The disclosed embodiments provide a refrigerant-based thermal storage system with increased versatility, reliability, lower cost components, reduced power consumption and ease of installation.

Description

CROSS REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of U.S. provisional application No. 61/470,841, entitled “Refrigerant Circuit with Integrated Multi-Mode Thermal Energy Storage,” filed Apr. 1, 2011 and the entire disclosures 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, 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.

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 Narayanamurthy et al., U.S. Pat. No. 7,854,129 issued to Narayanamurthy, U.S. Pat. No. 7,503,185 issued to Narayanamurthy et al., U.S. Pat. No. 7,827,807 issued to Narayanamurthy et al., U.S. Pat. No. 7,363,772 issued to Narayanamurthy, U.S. Pat. No. 7,793,515 issued to Narayanamurthy, U.S. patent application Ser. No. 11/837,356 filed Aug. 10, 2007 by Narayanamurthy et al., application Ser. No. 12/324,369 filed Nov. 26, 2008 by Narayanamurthy et al., U.S. patent application Ser. No. 12/371,229 filed Feb. 13, 2009 by Narayanamurthy et al., U.S. patent application Ser. No. 12/473,499 filed May 28, 2009 by Narayanamurthy et al., and U.S. patent application Ser. No. 12/335,871 filed Dec. 16, 2008 by Parsonnet et al. All of these patents and applications 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: 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; a thermal energy storage module containing a thermal storage media and a primary heat exchanger that facilitates heat transfer from the refrigerant to the thermal storage media in a charge mode, and the primary heat exchanger that facilitates heat transfer from the thermal storage media to cool the refrigerant in a discharge mode; a storage expansion device connected downstream of the condensing unit and upstream of the thermal energy storage module; an evaporator expansion device connected downstream of the condensing unit and the thermal energy storage module; an evaporator connected downstream of the evaporator expansion device; and, a valve system that facilitates flow of refrigerant to the storage module from the compressor or the condenser or the storage expansion device or the evaporator, the valve system that facilitates flow of refrigerant from the storage module to the compressor or the condenser or the evaporator expansion device.

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 a compressor and a condenser to create a high-pressure refrigerant; expanding the high-pressure refrigerant to produce expanded refrigerant and provide storage cooling with a thermal energy storage media via a primary heat exchanger, the primary heat exchanger that is constrained within a thermal energy storage module and in thermal communication with the storage media; and, returning the expanded refrigerant to the compressor; during a second time period: compressing and condensing the refrigerant with the compressor and the condenser to create the high-pressure refrigerant; expanding a first portion of the high-pressure refrigerant to produce the first expanded refrigerant and to provide storage cooling with the thermal energy storage media via the primary heat exchanger, the primary heat exchanger that is constrained within the thermal energy storage module and in thermal communication with the storage media; expanding a second portion of the high-pressure refrigerant to provide cooling to an evaporator to produce the second expanded refrigerant; and, returning the first expanded refrigerant and the second expanded refrigerant to the compressor; during a third time period: compressing the refrigerant with the compressor to create hot, high-pressure gas refrigerant; cooling and condensing a first portion of the hot, high-pressure gas refrigerant with the storage cooling to produce warm liquid refrigerant; condensing a second portion of the high-pressure refrigerant with the condenser; mixing the first portion and the second portion and expanding mixture to provide cooling in an evaporator to produce the expanded refrigerant; and, returning the expanded refrigerant to the compressor; during a fourth time period: compressing the refrigerant with the compressor to create the hot, high-pressure gas refrigerant; cooling and condensing the hot, high-pressure gas refrigerant with the storage cooling to produce the warm liquid refrigerant; condensing the warm liquid refrigerant with the condenser to create subcooled refrigerant; expanding the subcooled refrigerant to provide cooling in an evaporator to produce the expanded refrigerant; and, returning the expanded refrigerant to the compressor; during a fifth time period: compressing and condensing the refrigerant with the compressor and the condenser to create the high-pressure refrigerant; subcooling the high-pressure refrigerant with the storage cooling to produce subcooled liquid refrigerant; expanding the subcooled liquid refrigerant to provide cooling in the evaporator to produce the expanded refrigerant; and, returning the expanded refrigerant to the compressor; during a sixth time period: compressing and condensing the refrigerant with the compressor and the condenser to create the high-pressure refrigerant; expanding the high-pressure refrigerant to provide cooling in the evaporator and produce expanded refrigerant; desuperheating the expanded refrigerant with the storage cooling to produce desuperheated refrigerant; and, returning the desuperheated refrigerant to the compressor; compressing and condensing the refrigerant with the compressor and the condenser to create the high-pressure refrigerant; expanding the high-pressure refrigerant to provide cooling in the evaporator and produce expanded refrigerant; superheating the expanded refrigerant with the storage media to produce the superheated refrigerant; and, returning superheated refrigerant to the compressor; during an eighth time period; compressing and condensing the refrigerant with the compressor and the condenser to create the high-pressure refrigerant; expanding the high-pressure refrigerant to provide cooling in the evaporator and produce expanded refrigerant; returning the expanded refrigerant to the compressor.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings,

FIG. 1 schematically illustrates an embodiment of a refrigerant circuit with integrated multi-mode thermal energy storage.

FIG. 2 is a schematic illustration of the valve conditions for the embodiment of a thermal energy storage refrigerant circuit capable of multiple charging and discharging modes.

FIG. 3 schematically illustrates a configuration of an embodiment of a thermal energy storage refrigerant circuit with integrated trickle charge loop.

FIG. 4 schematically illustrates a configuration of an embodiment of a thermal energy storage refrigerant circuit with full capacity charge loop.

FIG. 5 schematically illustrates a configuration of an embodiment of a thermal energy storage refrigerant circuit with parallel condenser discharge loop.

FIG. 6 schematically illustrates a configuration of an embodiment of a thermal energy storage refrigerant circuit with hot vapor desuperheater discharge loop.

FIG. 7 schematically illustrates a configuration of an embodiment of a thermal energy storage refrigerant circuit with warm liquid subcooler discharge loop.

FIG. 8 schematically illustrates a configuration of an embodiment of a thermal energy storage refrigerant circuit with cold vapor desuperheater discharge loop.

FIG. 9 schematically illustrates a configuration of an embodiment of a thermal energy storage refrigerant circuit with suction line charge loop.

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 refrigerant circuit with integrated multi-mode thermal energy storage. The embodiments shown may function with or without an accumulator vessel (surge vessel) or URMV 102 (universal refrigerant management vessel), and is depicted in FIG. 1 with the vessel in place.

As illustrated in FIG. 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 charge modes, four discharge modes and one bypass mode are possible with the system as shown. These modes of charging and discharging the storage module include trickle charge, full-capacity charge, parallel condenser discharge, hot vapor desuperheater discharge, warm liquid subcooler discharge, cold vapor desuperheater discharge and suction line charges.

The charging modes utilize a compressor 110 to compress cold, low pressure refrigerant gas to hot, high-pressure gas. This refrigerant passes through valve V1 122 to a condenser 112 which removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser 112 as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid supply line where a portion of the warm liquid refrigerant is diverted by valve V3 126 to valve V4 128, which directs the diverted refrigerant through the storage expansion device 118. The storage expansion device 118 reduces the pressure of the warm liquid refrigerant to generate a cold mixed-phase refrigerant, which is directed to the heat exchanger 170 within the storage module 116.

This storage expansion device 118 may be a conventional or non-conventional thermal expansion valve, a static orifice, a capillary tube, a mixed-phase regulator and surge vessel (reservoir), or the like. In this mode, the heat exchanger 170 in the storage module 116 acts as an evaporator where the cold mixed-phase refrigerant absorbs heat from the storage media 160 that surrounds the heat exchanger 170 and vaporizes. The liquid refrigerant transfers cooling to thermal energy storage media 160 within the thermal energy storage module 116 (as shown, but not limited by way of example via a primary heat exchanger 170 within an insulated tank). Low-pressure vapor phase refrigerant is then returned to the compressor 110 via valve V7 134 where it is mixed with the portion of the cold vapor refrigerant returning to compressor 110 via valve V6 132 from the evaporator 114 that was split at valve V3 126 and passed through valve V5 130 and an evaporator expansion device 120. As with the storage expansion device 118, evaporator expansion device 120 may be a conventional or non-conventional thermal expansion valve, a static orifice, a capillary tube, a mixed-phase regulator and surge vessel (reservoir), or the like.

In order to meter the amount of refrigerant that is split by valve V3 126, a specialized valve and controller that modulates based on downstream pressures, for example, may be used to split the amount of refrigerant that is diverted to provide immediate cooling through evaporator 114 and the amount diverted to TES for providing cooling capacity, which may be utilized at a later time. Alternatively, the storage media 160 used in the storage module 116 can be selected in order to match the refrigerant evaporating temperature of the storage module 116 to that of the evaporator 114, effectively matching the pressure drop across the storage expansion device 118 and evaporator expansion device 120 resulting in a self-metering trickle charge configuration.

The thermal energy storage unit 116 shown in FIG. 1 may typically comprise an insulated tank that houses the primary heat exchanger 170 surrounded by a storage media 160 (e.g., solid, liquid coolant, eutectic or liquid phase material and/or solid phase material or the like [fluid/ice] depending on the current system mode). The primary heat exchanger 170 may typically further comprise a lower header assembly connected to an upper header assembly with a series of freezing and discharge coils to make a fluid/vapor loop within the insulated tank. Such systems are disclosed in the patents and applications referred to above, which are also incorporated by reference.

When operating in full-capacity charge mode, the compressor 110 is energized to compress cold, low pressure refrigerant gas to hot, high-pressure gas. This refrigerant passes through valve V1 122 and to a condenser 112, which removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser 112 as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid supply line where the entirety of the warm liquid refrigerant is diverted by valve V3 126 to valve V4 128, which directs the diverted refrigerant through the storage expansion device 118. Here, as in the previously described trickle charge mode, the storage expansion device 118 reduces the pressure of the warm liquid refrigerant to generate a cold mixed-phase refrigerant. In this mode, the heat exchanger 170 within the storage module 116 also acts as an evaporator where the cold mixed-phase refrigerant absorbs heat from the storage media 160 and vaporizes and transfers cooling to thermal energy storage media 160 within the thermal energy storage module 116. Low-pressure vapor phase refrigerant is then returned to the compressor 110 via valve V7 134. Thus, the entirety of the cooling provided by the compressor 110 and condenser 112 (typical conventional air conditioning or refrigeration unit) is transmitted, in one contemplated embodiment, from the heat exchanger 170 to the surrounding storage media (e.g., liquid phase material that is confined within an insulated tank and may produce a block of solid phase material (ice) surrounding the freezing coils and storing thermal energy in the process).

In parallel condenser discharge mode, all basic air conditioning/refrigerant AC/R components are active including the compressor 110, condenser 112, evaporator expansion device 120, and the evaporator 114. In this mode, the compressor 110 is energized to compress cold, low pressure refrigerant gas to hot, high-pressure gas. This refrigerant passes through valve V1 122 where a portion of the hot, high-pressure gas is diverted by valve V1 122 to the storage module 116 and heat exchanger 170, which acts as a condenser where the hot vapor rejects heat to the storage media 160, reduces temperature, and condenses. This warm liquid refrigerant is then sent to the evaporator expansion device 120 via valve V5 130 where it is mixed with warm liquid refrigerant exiting the condenser 112 via valve V3 126. The mixed warm liquid refrigerant is then expanded with the evaporator expansion device 120 and evaporator 114 to provide load cooling/refrigeration and returns to compressor 110 through valves V6 132 and V7 134 to complete the refrigeration loop.

Utilizing the heat exchanger 170 within the storage module 116 in this mode as a condenser, allows a greater amount of subcooling prior to the expansion process. This is accomplished by rejecting heat to the cold storage media 160 within the storage module 116, and improving the effectiveness of the condenser 112 by reducing the mass flow of refrigerant through condenser 112. Ultimately, the increased subcooling results in an efficiency improvement for the system by increasing the refrigeration effect of the evaporator 114. This increase in efficiency may allow an increased output by the evaporator 114 thereby effectively increasing the capacity of the AC/R system during high demand periods. This may allow a smaller system to be introduced into a new installation or to increase the capacity of an existing retrofit system application.

In the hot vapor desuperheater discharge mode, all basic AC/R components are active including the compressor 110, condenser 112, evaporator expansion device 120, and the evaporator 114. In this mode, the compressor 110 is energized to compress cold, low pressure refrigerant gas to hot, high-pressure gas. This refrigerant passes through valve V1 122 and is directed to the previously charged storage module 116 acting as a hot vapor desuperheater where the hot vapor refrigerant rejects heat to the storage media 160 via the heat exchanger 170 and reduces temperature. The vapor is then directed to the condenser 112 via valve V2 124 where additional atmospheric heat rejection and condensation occur. The refrigerant leaves the condenser 112 where the entirety of the subcooled refrigerant is diverted by valve V3 126 to valve V5 130 where refrigerant is then directed to the evaporator expansion device 120. The warm liquid refrigerant is expanded and then evaporated in evaporator 114 before being returned to compressor 110 through valves V6 132 and V7 134.

In this mode, using the storage module 116, acting as a hot vapor desuperheater, allows a greater amount of subcooling prior to the expansion process. This is accomplished by rejecting heat to the cold storage media 160 within the storage module 116, and improving the condenser 112 effectiveness by reducing the amount of heat rejection that must occur in the condenser 112 to desuperheat the hot vapor refrigerant. Instead, more of the condenser 112 heat rejection process is used to subcool the warm liquid refrigerant. Ultimately, the increased subcooling results in an efficiency improvement for the system by increasing the refrigeration effect of the evaporator 114. This increase in efficiency may also allow an increased output by the evaporator 114, thereby effectively increasing the capacity of the AC/R system during high demand periods. This may allow a smaller system to be introduced into a new installation or to increase the capacity of an existing retrofit system application.

In the warm liquid subcooler discharge mode, all basic AC/R components are active including the compressor 110, condenser 112, evaporator expansion device 120 and the evaporator 114. In this mode, the compressor 110 is energized to compress cold, low pressure refrigerant gas to hot, high-pressure gas. This refrigerant passes through valve V1 122 to a condenser 112, which removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser 112 as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid supply line where the entirety of the warm liquid refrigerant is diverted by valve V3 126 to valve V4 128, which directs the refrigerant directly to the heat exchanger within the storage module 116, acting as a warm liquid subcooler, where the warm liquid refrigerant rejects heat and reduces temperature by transferring heat to the previously cooled thermal storage media 160.

The cooled liquid refrigerant is then directed to the evaporator expansion device 120 via valve V5 130. The subcooled refrigerant is expanded and then evaporated in evaporator 114 before being returned to compressor 110 through valves V6 132 and V7 134. In this mode, using the storage module 116 as a warm liquid subcooler allows a greater amount of subcooling prior to the expansion process by rejecting heat to the cold storage media 160 within the storage module 116. Ultimately, the increased subcooling results in an efficiency improvement for the system by increasing the refrigeration effect of the evaporator 114. This increase in efficiency may allow an increased output by the evaporator 114, thereby effectively increasing the capacity of the AC/R system during high demand periods. This may allow a smaller system to be introduced into a new installation or to increase the capacity of an existing retrofit system application.

In cold vapor desuperheater discharge mode, all basic AC/R components are active including the compressor 110, condenser 112, evaporator expansion device 120, and the evaporator 114. In this mode, the compressor 110 is energized to compress cold, low pressure refrigerant gas to hot, high-pressure gas. This refrigerant passes through valve V1 122 to a condenser 112, which removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser 112 as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid supply line where the warm liquid refrigerant is diverted by valve V3 126 to valve V5 130 where refrigerant is then directed to the evaporator expansion device 120. The refrigerant is expanded and then evaporated in evaporator 114 in a conventional manner and the expanded refrigerant is then diverted by valve V6 132 to the pre-charged storage module 116 acting as a cold vapor desuperheater where the cold vapor refrigerant rejects heat to the storage media 160 and reduces temperature before being returned to compressor 110 through valve V7 134.

In this mode, using the storage module 116 as a cold vapor desuperheater, allows a greater amount of subcooling prior to the expansion process by rejecting heat to the cold storage media 160 within the storage module 116, and improving the condenser 112 effectiveness by reducing the amount of heat rejection that must occur in the condenser 112 to desuperheat the hot vapor refrigerant. Instead, more of the condenser 112 heat rejection process is used to subcool the warm liquid refrigerant. Ultimately, the increased subcooling results in an efficiency improvement for the system by increasing the refrigeration effect of the evaporator 114. This increase in efficiency may allow an increased output by the evaporator 114 thereby effectively increasing the capacity of the AC/R system during high demand periods. This may allow a smaller system to be introduced into a new installation or to increase the capacity of an existing retrofit system application.

In suction line charge mode, all basic AC/R components are active including the compressor 110, condenser 112, evaporator expansion device 120, and the evaporator 114. In this mode, the compressor 110 is energized to compress cold, low pressure refrigerant gas to hot, high-pressure gas. This refrigerant passes through valve V1 122 to a condenser 112, which removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser 112 as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid supply line where the warm liquid refrigerant is diverted by valve V3 126 to valve V5 130 where refrigerant is then directed to the evaporator expansion device 120. The refrigerant is expanded and then evaporated in evaporator 114 in a conventional manner and the expanded refrigerant is then diverted by valve V6 132 to the uncharged storage module 116 acting as a cold vapor superheater where residual cooling that remains in the effluent cold vapor refrigerant leaving the evaporator 114, is transferred to the storage media 160, and the temperature of the cold vapor refrigerant increases. The superheated vapor refrigerant exits the storage module 116 and returns to compressor 110 through valve V7 134.

In this mode, using the storage module 116 as a cold vapor superheater, allows an amount of charging (cooling) of the thermal storage media 160 prior to compressing the superheated refrigerant. This places more strain on the compressor 110, but allows an additional mode of charging the storage module while providing conventional cooling with the evaporator 114.

An additional loop may be utilized in the embodiment described in FIG. 1, which does not utilize TES. A bypass mode 199 may be achieved that acts as a standard AC/R system without utilization of the storage module 116. In this mode, the compressor 110 is energized to compress cold, low pressure refrigerant gas to hot, high-pressure gas. This refrigerant passes through valve V1 122 to a condenser 112, which removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser 112 as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid supply line where the warm liquid refrigerant is diverted by valve V3 126 to valve V5 130 where refrigerant is then directed to the evaporator expansion device 120. The refrigerant is expanded and then evaporated in evaporator 114 in a conventional manner and the expanded refrigerant is then diverted by valve V6 132 before being returned to compressor 110 through valve V7 134. In this mode, conventional AC/R may be utilized in situations where TES is not needed or desired.

As illustrated in FIG. 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. This system may be a single integrated system with all of the above disclosed modes present, or the contemplated system may include various combinations thereof.

FIG. 2 is a schematic illustration of the valve conditions for the embodiment of a thermal energy storage refrigerant circuit capable of multiple charging modes 180 and discharging modes 190 depicted in FIG. 1. As shown in FIG. 2, the valve state conditions are depicted for each of the seven valves V1 122-V7 134. For example, in the trickle charge mode, valve V1 122 allows flow from the compressor to the condenser and is depicted as condition (=). Valve V2 124 does not allow flow, or is inconsequential with regard to the flow condition and is depicted with a small box as condition (□). Valve V3 126 allows metered and proportional flow to both the storage expansion device 118 and the evaporator expansion device 120 and is depicted as condition (). Thus, each of the charge mode 180 valve configurations is shown, and in a similar manner the four discharge modes 190 and a bypass mode 199 are schematically illustrated.

FIG. 3 illustrates an AC/R trickle charge loop. In this particular charging loop, a compressor 110 compresses cold, low pressure refrigerant gas to hot, high-pressure gas. This refrigerant passes to a condenser 112, which removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser 112 as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid supply line where a portion of the warm liquid refrigerant is diverted by a valve, which directs the diverted refrigerant through the storage expansion device 118. The storage expansion device 118 reduces the pressure of the warm liquid refrigerant to generate a cold mixed-phase refrigerant. In this loop, the storage module acts as an evaporator where the cold mixed-phase refrigerant absorbs heat from the storage media 160 and vaporizes. This storage expansion device 118 may be a conventional or non-conventional thermal expansion valve, a static orifice, a capillary tube, a mixed-phase regulator and surge vessel (reservoir), or the like.

The liquid refrigerant transfers cooling to thermal energy storage media 160 within the thermal energy storage module 116 (shown here as a primary heat exchanger 170 within an insulated tank). Low-pressure vapor phase refrigerant is then returned to the compressor 110 where it is mixed with the portion of the cold vapor refrigerant returning to compressor 110 from the evaporator 114 that was split at the valve and passed through an evaporator expansion device 120. As with the storage expansion device 118, evaporator expansion device 120 may be a conventional or non-conventional thermal expansion valve, a static orifice, a capillary tube, a mixed-phase regulator and surge vessel (reservoir), or the like.

As was described in FIG. 1, in order to meter the amount of refrigerant that is split, a specialized valve may be used to meter the amount of refrigerant that is diverted to each branch to provide immediate cooling through evaporator 114, and to the amount diverted to TES for providing cooling capacity, which may be utilized at a later time (e.g., a valve and controller that modulates based on downstream pressures). Alternatively, the storage media 160 used in the storage module 116 can be selected in order to match the refrigerant evaporating temperature of the storage module 116 to that of the evaporator 114, effectively matching the pressure drop across the storage expansion device 118 and evaporator expansion device 120 and resulting in a self-metering trickle charge configuration.

The thermal energy storage unit 116 shown in FIGS. 1 and 3-9 may typically comprise an insulated tank that houses the primary heat exchanger 170 surrounded by, for example, solid, liquid coolant, eutectic or liquid phase material and/or solid phase material or the like, (fluid/ice) depending on the current system mode). The primary heat exchanger 170 may typically further comprise a lower header assembly connected to an upper header assembly with a series of freezing and discharge coils to make a fluid/vapor loop within the insulated tank. Such systems are disclosed in the patents and applications referred to above, which are incorporated by reference.

FIG. 4 illustrates an AC/R full-capacity charge loop. In this particular charging loop, the compressor 110 is energized to compress cold, low pressure refrigerant gas to hot, high-pressure gas. This refrigerant passes to a condenser 112, which removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser 112 as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid supply line where the entirety of the warm liquid refrigerant is directed to the storage expansion device 118. Here as in the previously described trickle charge loop, the storage expansion device 118 reduces the pressure of the warm liquid refrigerant to generate a cold mixed-phase refrigerant. In this mode, the storage module also acts as an evaporator where the cold mixed-phase refrigerant absorbs heat from the storage media 160 and vaporizes and transfers cooling to thermal energy storage media 160 within the thermal energy storage module 116. Low-pressure vapor phase refrigerant is then returned to the compressor 110. Thus, the entirety of the cooling provided by the compressor 110 and condenser 112 (typical conventional air conditioning or refrigeration unit) is transmitted, in one contemplated embodiment, from the freezing coils to the surrounding liquid phase material that is confined within an insulated tank and may produce a block of solid phase material (ice) surrounding the freezing coils and storing thermal energy in the process.

FIG. 5 illustrates an AC/R parallel condenser discharge loop. In this particular discharge loop, the compressor 110 is energized to compress cold, low pressure refrigerant gas to hot, high-pressure gas. This refrigerant passes through a valve where a portion of the hot, high-pressure gas is diverted to the storage module 116, which acts as a condenser where the hot vapor rejects heat to the storage media 160, reduces temperature, and condenses. This warm liquid refrigerant is then sent to the evaporator expansion device 120 where it is mixed with warm liquid refrigerant exiting the condenser 112. The mixed warm liquid refrigerant is then expanded with the evaporator expansion device 120 and evaporator 114 to provide load cooling/refrigeration and returns to compressor 110 to complete the refrigeration loop.

FIG. 6 illustrates an AC/R hot vapor desuperheater discharge loop. In this particular discharge loop, the compressor 110 is energized to compress cold, low pressure refrigerant gas to hot, high-pressure gas. This refrigerant is directed to the previously charged storage module 116 acting as a hot vapor desuperheater where the hot vapor refrigerant rejects heat to the storage media 160 and reduces temperature. The vapor is then directed to the condenser 112, where additional atmospheric heat rejection and condensation occur. The refrigerant leaves the condenser 112, where the entirety of the desuperheated refrigerant is directed to the evaporator expansion device 120. The warm liquid refrigerant is expanded and then evaporated in evaporator 114 before being returned to compressor 110.

FIG. 7 illustrates an AC/R warm liquid subcooler discharge loop. In this particular discharge loop, the compressor 110 is energized to compress cold, low pressure refrigerant gas to hot, high-pressure gas. This refrigerant passes to a condenser 112, which removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser 112 as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid supply line where the entirety of the warm liquid refrigerant is directed to the storage module 116, which acts as a warm liquid subcooler where the warm liquid refrigerant rejects heat to the storage media 160 and reduces temperature by transferring heat to the previously cooled thermal storage media 160. The cooled liquid refrigerant is then directed to the evaporator expansion device 120. The subcooled refrigerant is expanded and then evaporated in evaporator 114 before being returned to compressor 110.

FIG. 8 illustrates an AC/R cold vapor desuperheater discharge loop. In this particular discharge loop, the compressor 110 is energized to compress cold, low pressure refrigerant gas to hot, high-pressure gas. This refrigerant passes to a condenser 112, which removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser 112 as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid supply line where the warm liquid refrigerant is then directed to the evaporator expansion device 120. The refrigerant is expanded and then evaporated in evaporator 114 in a conventional manner and the expanded refrigerant is then diverted to the pre-charged storage module 116, acting as a cold vapor desuperheater where the cold vapor refrigerant rejects heat to the storage media 160 and reduces temperature before being returned to compressor 110.

FIG. 9 illustrates an AC/R suction line charge loop. In this particular charging loop, the configuration of the loop is the same as the cold vapor desuperheater discharge loop illustrated in FIG. 8, except that the storage module 116 is being charged instead of being discharged. In this loop, the compressor 110 is energized to compress cold, low pressure refrigerant gas to hot, high-pressure gas. This refrigerant passes to a condenser 112, which removes much of the heat in the gas and discharges the heat to the atmosphere. The refrigerant leaves the condenser 112 as a warm, high-pressure liquid refrigerant delivered through a high-pressure liquid supply line where the warm liquid refrigerant is diverted by valve V3 126 through valve V5 130 to the evaporator expansion device 120. The evaporator expansion device 120 reduces the pressure of the warm liquid refrigerant to generate a cold mixed-phase refrigerant. In this mode, the evaporator 114 provides cooling as during typical AC/R operation. The cold vapor refrigerant exits the evaporator 114 and is diverted by valve V6 132 to the storage module 116 where residual cooling that remains in the effluent refrigerant leaving the evaporator 114 is transferred to the storage media 160, and the temperature of the cold vapor refrigerant increases. The superheated vapor refrigerant exits the storage module 116 and returns to compressor 110.

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.

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. An integrated 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; a thermal energy storage module containing a thermal storage media and a primary heat exchanger that facilitates heat transfer from said refrigerant to said thermal storage media in a charge mode, and said primary heat exchanger that facilitates heat transfer from said thermal storage media to cool said refrigerant in a discharge mode; a storage expansion device connected downstream of said condensing unit and upstream of said thermal energy storage module; an evaporator expansion device connected downstream of said condensing unit and said thermal energy storage module; an evaporator connected downstream of said evaporator expansion device; and, a valve system that facilitates flow of refrigerant to said storage module from said compressor or said condenser or said storage expansion device or said evaporator, said valve system that facilitates flow of refrigerant from said storage module to said compressor or said condenser or said evaporator expansion device.

2. The system of claim 1 further comprising:

a refrigerant management vessel in fluid communication with, and located downstream of said condenser.

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

4. The system of claim 1 wherein said evaporator expansion device is chosen from the group consisting of a thermal expansion valve, an electronic expansion valve, a static orifice, a capillary tube, and a mixed-phase regulator.

5. The system of claim 1 wherein at least a portion of said thermal storage media changes phase in said charge mode and said discharge mode.

6. The system of claim 1 wherein said thermal storage media is a eutectic material.

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

8. The system of claim 1 wherein said thermal storage media does not store heat in the form of latent heat.

9. The system of claim 1 wherein said evaporator is at least one mini-split evaporator.

10. The system of claim 1 wherein said charge mode is operated concurrent with and said discharge mode.

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

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

13. A method of providing cooling with an integrated thermal energy storage and cooling system comprising:

charging a thermal energy storage module of said thermal energy storage and cooling system during a first time period by: compressing and condensing a refrigerant with a compressor and a condenser to create a high-pressure refrigerant; dividing said a high-pressure refrigerant downstream of said condenser into a first high-pressure refrigerant and a second high-pressure refrigerant; expanding said first said high-pressure refrigerant to provide storage cooling with a thermal energy storage media via a primary heat exchanger thereby producing a first expanded refrigerant, said primary heat exchanger that is constrained within a thermal energy storage module and in thermal communication with said storage media; and, returning said first expanded refrigerant to said compressor;

expanding said second high-pressure refrigerant to provide cooling in said evaporator thereby producing a second expanded refrigerant; and, returning said expanded refrigerant and said secondary expanded refrigerant to said compressor.

14. The method of claim 13 further comprising the step:

bypassing said thermal energy storage module of said thermal energy storage and cooling system during a second time period by: compressing and condensing said refrigerant with said compressor and said condenser to create said high-pressure refrigerant; expanding said high-pressure refrigerant to provide cooling in said evaporator and produce expanded refrigerant; and, returning said expanded refrigerant to said compressor.

15. The method of claim 13 further comprising the step:

expanding at least a portion of said high-pressure refrigerant with an expansion device chosen from the group consisting of a storage expansion device, an evaporator and an evaporator downstream of an evaporator expansion device.

16. A method of providing cooling with an integrated thermal energy storage and cooling system comprising:

charging a thermal energy storage module of said thermal energy storage and cooling system during a first time period by: compressing and condensing a refrigerant with a compressor and a condenser to create a high-pressure refrigerant; expanding at least a portion of said high-pressure refrigerant to produce expanded refrigerant and provide storage cooling with a thermal energy storage media via a primary heat exchanger, said primary heat exchanger that is constrained within a thermal energy storage module and in thermal communication with said storage media; and, returning said expanded refrigerant to said compressor;

discharging said thermal energy storage module of said thermal energy storage and cooling system during a second time period by: cooling and condensing a first portion of a hot, high-pressure gas refrigerant from said compressor with said storage cooling to produce warm liquid refrigerant; condensing a second portion of said high-pressure refrigerant from said compressor with said condenser; mixing said first portion and said second portion and expanding said mixture to provide cooling in an evaporator to produce said expanded refrigerant; and, returning said expanded refrigerant to said compressor.

17. The method of claim 16 further comprising the step:

discharging said thermal energy storage module of said thermal energy storage and cooling system during a third time period by: cooling and condensing a hot, high-pressure gas refrigerant from said compressor with said storage cooling to produce warm liquid refrigerant; condensing said warm liquid refrigerant with said condenser to create subcooled refrigerant; expanding said subcooled refrigerant to provide cooling in an evaporator to produce said expanded refrigerant; and, returning said expanded refrigerant to said compressor.

18. The method of claim 16 further comprising the step:

discharging said thermal energy storage module of said thermal energy storage and cooling system during a third time period by:

subcooling said high-pressure refrigerant with said storage cooling to produce said subcooled liquid refrigerant;

expanding said subcooled liquid refrigerant to provide cooling in said evaporator to produce said expanded refrigerant; and,

returning said expanded refrigerant to said compressor.

19. The method of claim 16 further comprising the step:

discharging said thermal energy storage module of said thermal energy storage and cooling system during a third time period by: expanding said high-pressure refrigerant exiting said condenser to provide cooling in said evaporator and produce expanded refrigerant; desuperheating said expanded refrigerant with said storage cooling to produce desuperheated refrigerant; and, returning said desuperheated refrigerant to said compressor.

20. The method of claim 16 further comprising the step:

bypassing said thermal energy storage module of said thermal energy storage and cooling system during a third time period by: compressing and condensing said refrigerant with said compressor and said condenser to create said high-pressure refrigerant; expanding said high-pressure refrigerant to provide cooling in said evaporator and produce expanded refrigerant; and, returning said expanded refrigerant to said compressor.

21. The method of claim 16 further comprising the step:

expanding at least a portion of said high-pressure refrigerant with an expansion device chosen from the group consisting of a storage expansion device, an evaporator and an evaporator downstream of an evaporator expansion device.

22. A method of providing cooling with an integrated thermal energy storage and cooling system comprising:

charging a thermal energy storage module of said thermal energy storage and cooling system during a first time period by: compressing and condensing a refrigerant with a compressor and a condenser to create a high-pressure refrigerant; expanding at least a portion of said high-pressure refrigerant to produce expanded refrigerant and provide storage cooling with a thermal energy storage media via a primary heat exchanger, said primary heat exchanger that is constrained within a thermal energy storage module and in thermal communication with said storage media; and, returning said expanded refrigerant to said compressor;

discharging said thermal energy storage module of said thermal energy storage and cooling system during a second time period by: cooling and condensing a hot, high-pressure gas refrigerant from said compressor with said storage cooling to produce warm liquid refrigerant; condensing said warm liquid refrigerant with said condenser to create subcooled refrigerant; expanding said subcooled refrigerant to provide cooling in an evaporator to produce said expanded refrigerant; and, returning said expanded refrigerant to said compressor.

23. The method of claim 22 further comprising the step:

discharging said thermal energy storage module of said thermal energy storage and cooling system during a second time period by: cooling and condensing a first portion of a hot, high-pressure gas refrigerant from said compressor with said storage cooling to produce warm liquid refrigerant; condensing a second portion of said high-pressure refrigerant from said compressor with said condenser; mixing said first portion and said second portion and expanding said mixture to provide cooling in an evaporator to produce said expanded refrigerant; and, returning said expanded refrigerant to said compressor.

24. The method of claim 22 further comprising the step:

discharging said thermal energy storage module of said thermal energy storage and cooling system during a third time period by:

subcooling said high-pressure refrigerant with said storage cooling to produce said subcooled liquid refrigerant;

expanding said subcooled liquid refrigerant to provide cooling in said evaporator to produce said expanded refrigerant; and,

returning said expanded refrigerant to said compressor.

25. The method of claim 22 further comprising the step:

discharging said thermal energy storage module of said thermal energy storage and cooling system during a third time period by: expanding said high-pressure refrigerant exiting said condenser to provide cooling in said evaporator and produce expanded refrigerant; desuperheating said expanded refrigerant with said storage cooling to produce desuperheated refrigerant; and, returning said desuperheated refrigerant to said compressor.

26. The method of claim 22 further comprising the step:

bypassing said thermal energy storage module of said thermal energy storage and cooling system during a third time period by: compressing and condensing said refrigerant with said compressor and said condenser to create said high-pressure refrigerant; expanding said high-pressure refrigerant to provide cooling in said evaporator and produce expanded refrigerant; and, returning said expanded refrigerant to said compressor.

27. The method of claim 22 further comprising the step:

expanding at least a portion of said high-pressure refrigerant with an expansion device chosen from the group consisting of a storage expansion device, an evaporator and an evaporator downstream of an evaporator expansion device.

28. A method of providing cooling with an integrated thermal energy storage and cooling system comprising:

charging a thermal energy storage module of said thermal energy storage and cooling system during a first time period by: compressing and condensing a refrigerant with a compressor and a condenser to create a high-pressure refrigerant; expanding at least a portion of said high-pressure refrigerant to produce expanded refrigerant and provide storage cooling with a thermal energy storage media via a primary heat exchanger, said primary heat exchanger that is constrained within a thermal energy storage module and in thermal communication with said storage media; and, returning said expanded refrigerant to said compressor;

discharging said thermal energy storage module of said thermal energy storage and cooling system during a second time period by: subcooling said high-pressure refrigerant with said storage cooling to produce said subcooled liquid refrigerant; expanding said subcooled liquid refrigerant to provide cooling in said evaporator to produce said expanded refrigerant; and, returning said expanded refrigerant to said compressor.

29. The method of claim 28 further comprising the step:

discharging said thermal energy storage module of said thermal energy storage and cooling system during a second time period by: cooling and condensing a first portion of a hot, high-pressure gas refrigerant from said compressor with said storage cooling to produce warm liquid refrigerant; condensing a second portion of said high-pressure refrigerant from said compressor with said condenser; mixing said first portion and said second portion and expanding said mixture to provide cooling in an evaporator to produce said expanded refrigerant; and, returning said expanded refrigerant to said compressor.

30. The method of claim 28 further comprising the step:

discharging said thermal energy storage module of said thermal energy storage and cooling system during a third time period by: cooling and condensing a hot, high-pressure gas refrigerant from said compressor with said storage cooling to produce warm liquid refrigerant; condensing said warm liquid refrigerant with said condenser to create subcooled refrigerant; expanding said subcooled refrigerant to provide cooling in an evaporator to produce said expanded refrigerant; and, returning said expanded refrigerant to said compressor.

31. The method of claim 28 further comprising the step:

discharging said thermal energy storage module of said thermal energy storage and cooling system during a third time period by: expanding said high-pressure refrigerant exiting said condenser to provide cooling in said evaporator and produce expanded refrigerant; desuperheating said expanded refrigerant with said storage cooling to produce desuperheated refrigerant; and, returning said desuperheated refrigerant to said compressor.

32. The method of claim 28 further comprising the step:

bypassing said thermal energy storage module of said thermal energy storage and cooling system during a third time period by: compressing and condensing said refrigerant with said compressor and said condenser to create said high-pressure refrigerant; expanding said high-pressure refrigerant to provide cooling in said evaporator and produce expanded refrigerant; and, returning said expanded refrigerant to said compressor.

33. The method of claim 28 further comprising the step:

expanding at least a portion of said high-pressure refrigerant with an expansion device chosen from the group consisting of a storage expansion device, an evaporator and an evaporator downstream of an evaporator expansion device.

34. A method of providing cooling with an integrated thermal energy storage and cooling system comprising:

charging a thermal energy storage module of said thermal energy storage and cooling system during a first time period by: compressing and condensing a refrigerant with a compressor and a condenser to create a high-pressure refrigerant; expanding at least a portion of said high-pressure refrigerant to produce expanded refrigerant and provide storage cooling with a thermal energy storage media via a primary heat exchanger, said primary heat exchanger that is constrained within a thermal energy storage module and in thermal communication with said storage media; and, returning said expanded refrigerant to said compressor;

discharging said thermal energy storage module of said thermal energy storage and cooling system during a second time period by: expanding said high-pressure refrigerant exiting said condenser to provide cooling in said evaporator and produce expanded refrigerant; desuperheating said expanded refrigerant with said storage cooling to produce desuperheated refrigerant; and, returning said desuperheated refrigerant to said compressor.

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

discharging said thermal energy storage module of said thermal energy storage and cooling system during a second time period by: cooling and condensing a first portion of a hot, high-pressure gas refrigerant from said compressor with said storage cooling to produce warm liquid refrigerant; condensing a second portion of said high-pressure refrigerant from said compressor with said condenser; mixing said first portion and said second portion and expanding said mixture to provide cooling in an evaporator to produce said expanded refrigerant; and, returning said expanded refrigerant to said compressor.

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

discharging said thermal energy storage module of said thermal energy storage and cooling system during a third time period by: cooling and condensing a hot, high-pressure gas refrigerant from said compressor with said storage cooling to produce warm liquid refrigerant; condensing said warm liquid refrigerant with said condenser to create subcooled refrigerant; expanding said subcooled refrigerant to provide cooling in an evaporator to produce said expanded refrigerant; and, returning said expanded refrigerant to said compressor.

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

discharging said thermal energy storage module of said thermal energy storage and cooling system during a third time period by:

subcooling said high-pressure refrigerant with said storage cooling to produce said subcooled liquid refrigerant;

expanding said subcooled liquid refrigerant to provide cooling in said evaporator to produce said expanded refrigerant; and,

returning said expanded refrigerant to said compressor.

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

bypassing said thermal energy storage module of said thermal energy storage and cooling system during a third time period by: compressing and condensing said refrigerant with said compressor and said condenser to create said high-pressure refrigerant; expanding said high-pressure refrigerant to provide cooling in said evaporator and produce expanded refrigerant; and, returning said expanded refrigerant to said compressor.

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

expanding at least a portion of said high-pressure refrigerant with an expansion device chosen from the group consisting of a storage expansion device, an evaporator and an evaporator downstream of an evaporator expansion device.

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 a compressor and a condenser to create a high-pressure refrigerant; expanding said high-pressure refrigerant to produce expanded refrigerant and provide storage cooling with a thermal energy storage media via a primary heat exchanger, said primary heat exchanger that is constrained within a thermal energy storage module and in thermal communication with said storage media; and, returning said expanded refrigerant to said compressor;

during a second time period: compressing and condensing said refrigerant with said compressor and said condenser to create said high-pressure refrigerant; expanding a first portion of said high-pressure refrigerant produce said first expanded refrigerant and to provide storage cooling with said thermal energy storage media via said primary heat exchanger, said primary heat exchanger that is constrained within said thermal energy storage module and in thermal communication with said storage media; expanding a second portion of said high-pressure refrigerant to provide cooling to an evaporator to produce said second expanded refrigerant; and, returning said first expanded refrigerant and said second expanded refrigerant to said compressor;

during a third time period: compressing said refrigerant with said compressor to create hot, high-pressure gas refrigerant; cooling and condensing a first portion of said hot, high-pressure gas refrigerant with said storage cooling to produce warm liquid refrigerant; condensing a second portion of said high-pressure refrigerant with said condenser; mixing said first portion and said second portion and expanding said mixture to provide cooling in an evaporator to produce said expanded refrigerant; and, returning said expanded refrigerant to said compressor;

during a fourth time period: compressing said refrigerant with said compressor to create said hot, high-pressure gas refrigerant; cooling and condensing said hot, high-pressure gas refrigerant with said storage cooling to produce said warm liquid refrigerant; condensing said warm liquid refrigerant with said condenser to create subcooled refrigerant; expanding said subcooled refrigerant to provide cooling in an evaporator to produce said expanded refrigerant; and, returning said expanded refrigerant to said compressor;

during a fifth time period: compressing and condensing said refrigerant with said compressor and said condenser to create said high-pressure refrigerant; subcooling said high-pressure refrigerant with said storage cooling to produce said subcooled liquid refrigerant; expanding said subcooled liquid refrigerant to provide cooling in said evaporator to produce said expanded refrigerant; and, returning said expanded refrigerant to said compressor;

during a sixth time period: compressing and condensing said refrigerant with said compressor and said condenser to create said high-pressure refrigerant; expanding said high-pressure refrigerant to provide cooling in said evaporator and produce expanded refrigerant; desuperheating said expanded refrigerant with said storage cooling to produce desuperheated refrigerant; and, returning said desuperheated refrigerant to said compressor;

during a seventh time period; compressing and condensing said refrigerant with said compressor and said condenser to create said high-pressure refrigerant; expanding said high-pressure refrigerant to provide cooling in said evaporator and produce expanded refrigerant; superheating said expanded refrigerant with said storage media to produce superheated refrigerant; and, returning said superheated refrigerant to said compressor;

during an eighth time period; compressing and condensing said refrigerant with said compressor and said condenser to create said high-pressure refrigerant; expanding said high-pressure refrigerant to provide cooling in said evaporator and produce expanded refrigerant; and, returning said expanded refrigerant to said compressor.