Heat pump with thermal energy transfer unit and method

Abstract

A thermal energy transfer unit is used in conjunction with a conventional Freon based heat pump system. One or several thermal energy transfer units are operatively interconnected to one or several Freon based heat pump systems and share a common energy storage tank. Each thermal energy transfer unit converts energy from a compressor and condensing coil of the conventional heat pump system and stores it in the common energy storage tank when electricity is in low demand. Each thermal energy transfer unit retrieves stored energy from the common storage tank and provides air conditioning without the use of the compressor when electricity is in high demand. Each thermal energy transfer unit can be disabled to allow the heat pump units to perform as if they and the energy storage tank were not connected. One or all of the units can be disabled without affecting the performance or purpose of the others.

1 . An improved method for heating and cooling a structure using a Freon based heat pump system, comprising:
 a first refrigerant based heat exchanger capable of acting as either an evaporator or a condenser and adapted to absorb thermal energy from a structure in a cooling mode and supply thermal energy to the structure in a heating mode;   a second refrigerant based heat exchanger also capable of acting as either an evaporator or a condenser and adapted to absorb thermal energy from ambient atmosphere in a one mode and being adapted to transfer thermal energy to ambient atmosphere in a different mode;   a refrigerant distribution loop containing a compressible Freon based refrigerant and connecting the first and second heat exchangers in fluid flow communication;   a refrigerant compressor adapted to cycle the refrigerant through the refrigerant distribution loop and the first and second heat exchangers;   a reversing valve for converting the system from one of the aforesaid heating and cooling modes to the other of the modes by reversing the flow of Freon based refrigerant in the refrigerant flow loop; and   wherein the improved method comprises the steps of:   providing a thermal energy transfer unit in heat exchange relationship to the refrigerant distribution loop for applying energy conversion and storage to the Freon based heat pump system associated with the structure as the flow of Freon is reversed in the refrigerant flow loop during the cycling of the heating and cooling modes of operation of the system, the thermal energy transfer unit including a non-freezing liquid thermal storage media located in a thermal storage tank.   
   
   
       2 . The method of  claim 1 , further comprising the steps of:
 utilizing the thermal energy transfer unit to transfer heat from the thermal storage media in the thermal storage tank to the first heat exchanger of the Freon based heat pump system where it is rejected to outside air;   transferring heat from inside air within the structure to the thermal storage media in the thermal storage tank without the compressor operating; and   thereafter, allowing the first heat exchanger to transfer heat from the inside air of the structure to outside air in the same manner that such heat transfer was accomplished before the thermal energy transfer unit and thermal storage tank were added to the existing Freon based heat pump system.   
   
   
       3 . The method of  claim 2 , wherein the first refrigerant based heat exchanger includes an outside coil which acts as the evaporator in the system when the system is in the heating mode for heating the structure, and wherein the outside coil tends to ice up during the heating mode operation, normally requiring a thawing step between the cooling and heating modes of the system; and
 wherein the outside coil is thawed without the use of electric heating elements by reversing the flow of refrigerant in the refrigerant loop, thereby causing the outside coil to act as a condenser, the heat transfer between the refrigerant loop in the heat pump system and the storage media in the thermal storage tank being used to cool the thermal storage media and make ice in the thermal storage tank   
   
   
       4 . The method of  claim 3 , wherein the thermal storage tank has a fluid flow line and a fluid pump for pumping non-freezing liquid to and from the storage tank to the thermal energy transfer unit, and wherein the system includes an external heating element which is in heat exchange contact with the flow line to heat the liquid being circulated to the storage tank during the thawing step. 
   
   
       5 . A method of air conditioning and heating a structure using a Freon based heat pump system including a first refrigerant based heat exchanger capable of acting as either an evaporator or a condenser and adapted to absorb thermal energy from a structure in a cooling mode and supply thermal energy to the structure in a heating mode, and also including a second refrigerant based heat exchanger also capable of acting as either an evaporator or a condenser and adapted to absorb thermal energy from ambient atmosphere in a one mode and being adapted to transfer thermal energy to ambient atmosphere in a different mode, the heat pump system also including a refrigerant distribution loop containing a compressible Freon based refrigerant and including a compressor for cycling the refrigerant between a gaseous state and a liquid state, the improvement comprising the steps of:
 locating a thermal energy transfer unit in proximity to the structure, for applying energy conversion and storage to the existing conventional Freon based heat pump, including the steps of:   locating a thermal storage tank remotely from the thermal energy transfer unit and connecting the storage tank to the thermal energy transfer unit by a fluid flow line;   providing a pump for circulating non-freezing liquid in the fluid flow line to and from the storage tank for transferring heat to and from the storage tank;   wherein the thermal energy transfer unit includes an auxiliary heat exchanger to transfer heat from the non-freezing liquid to Freon being circulated within the refrigerant loop when storing energy in the tank and wherein the same auxiliary heat exchanger is used to transfer the heat in the Freon to the non freezing liquid, and thus to the tank, when air conditioning is performed without the compressor running, the heat transfer without the use of the compressor being accomplished by condensing the Freon to a liquid state and then pumping the liquid Freon into the structure to absorb heat where it vaporizes, and wherein the Freon is then circulated in heat exchange relationship with the auxiliary heat exchanger where it transfers its heat to the non freezing liquid and condenses to its liquid state after it absorbs heat and vaporizes inside the structure.   
   
   
       6 . The method of  claim 5 , wherein the thermal energy transfer unit allows normal air conditioning to be performed by the operation of the condenser as if the thermal energy transfer unit were not present, in which case heat is neither being added to nor extracted from the non freezing liquid in the storage tank and the liquid pump in the fluid flow line is not running. 
   
   
       7 . The method of  claim 6 , wherein the thermal energy storage tank uses a method for storing energy selected from the group consisting of: lowering the temperature of a liquid located within an insulated tank; using an ice on pipe storage tank; using an ice ball storage tank; and using an ice slurry method for storing thermal energy. 
   
   
       8 . A thermal energy transfer unit, comprising:
 at least one auxiliary heat exchanger for transferring heat from a conventional heat pump system having a mechanical compressor in a closed loop refrigeration circuit to a non-freezing liquid medium that, in turn, transfers that heat to or from at least one thermal storage tank;   pump means for circulating the non-freezing liquid medium;   a valve control circuit for controlling the flow of the non-freezing liquid medium to the conventional heat pump system to enable the transfer of heat to the thermal storage tank without the mechanical compressor running.   
   
   
       9 . The thermal energy transfer unit of  claim 7 , wherein the valve control circuit includes a series of valves which are used to start, stop and regulate the flow of heat from the conventional heat pump system to or from the thermal storage tank, the valve control circuit also functioning to allow heat to be transferred by the heat pump system as if the thermal energy transfer unit and thermal storage tank were not present in the system. 
   
   
       10 . The thermal energy transfer unit of  claim 9 , further comprising:
 a plurality of thermal energy transfer units used in association with a plurality of heat pump systems to transfer heat to or from one or more shared thermal energy storage tanks.   
   
   
       11 . The thermal energy transfer unit of  claim 5 , wherein the thermal energy transfer operates to duplicate the operation of a conventional air conditioner condensing unit while operating in the cooling mode, but without the conventional air conditioner condensing unit operating.