Integration of a thermal energy storage unit with an external HVAC system

1 . A refrigerant-based thermal energy storage and cooling system that operates in two modes, an ice make mode and an ice melt mode, which provides cooling to an external heating, ventilation and air conditioning (HVAC) unit, wherein the external HVAC unit comprises an HVAC controller communicatively coupled with the thermal energy storage and cooling system, an HVAC condenser, an HVAC blower, and an HVAC coil, the thermal energy storage and storage system comprising:

a first refrigerant loop that circulates a first refrigerant, comprising:

an evaporator that cools the first refrigerant;

a second refrigerant loop containing a second refrigerant, comprising:

a tank filled with a fluid capable of a phase change between liquid and solid, wherein the tank uses the second refrigerant to cool the fluid and to freeze at least a portion of the fluid within the tank, wherein during ice melt mode the frozen fluid cools the second refrigerant;

an isolating heat exchanger, which has a portion inside the first refrigerant loop and a portion inside the second refrigerant loop, and which during ice make mode uses the cooled first refrigerant circulating in the first refrigerant loop to cool the second refrigerant circulating within the second refrigerant loop;

a thermal cooling (TC) controller operable to (1) receive a signal from the external HVAC system, wherein the received signal indicates that cooling is requested, and (2) upon receiving the signal, to transmit a signal to the HVAC controller to halt the HVAC condenser;

a refrigerant pump, which, upon receiving a signal from the TC controller indicating that cooling is requested, pumps cooled second refrigerant from the second refrigerant loop;

a thermal cooling (TC) evaporator coil that receives the cooled second refrigerant from the second refrigerant loop; and

a physical integration element, mounted within the HVAC unit adjacent to the HVAC coil and the HVAC blower, which houses the TC evaporator coil and provides connection points for a supply line and return line, thus enabling the TC evaporator coil to transfer cooling to the HVAC coil.

2 . The system of claim 1 wherein the first refrigerant loop comprises:

a condensing unit, said condensing unit comprising a compressor and a first condenser; and

an expansion device connected downstream of said condensing unit; and

a first evaporator on a primary side of an isolating heat exchanger located downstream of said expansion device;

wherein the first evaporator evaporates at least a portion of the first refrigerant to cool the first refrigerant.

3 . The system of claim 2 wherein said expansion device is a mixed-phase regulator.

4 . The system of claim 1 wherein the second refrigerant loop further comprises:

a second condenser on a secondary side of said isolating heat exchanger; and

the liquid refrigerant pump for distributing the second refrigerant from to the evaporator coil; and

wherein the tank further comprises:

a primary heat exchanger in fluid communication with said second condenser.

5 . The system of claim 4 wherein the second refrigerant loop further comprises:

a refrigerant management vessel connected to receive the cooled second refrigerant from the tank;

and wherein the liquid refrigerant pump distributes the second refrigerant from the refrigerant management vessel to the evaporator coil.

6 . The system of claim 5 wherein the second refrigerant loop further comprises:

a valve structure for isolating the second refrigeration loop within the isolating heat exchanger, the primary heat exchanger, the refrigerant management vessel, and the liquid refrigerant pump to form an ice-make circuit.

7 . The system of claim 1 wherein the HVAC blower blows warm air across both the TC evaporator coil and the HVAC coil.

8 . The system of claim 7 wherein the external HVAC controller is operable to transmit an electronic signal to the TC controller, wherein the signal indicates either that cooling is requested or that cooling is not requested.

9 . The system of claim 7 wherein the TC evaporator coil is positioned within 0.1 to 6 inches of the evaporator coil of the external HVAC unit.

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

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

12 . The system of claim 1 wherein said first refrigerant is a different material from said second refrigerant.