Abstract:
A cold storage facility energy transfer system has a building which includes walls, a roof, and a floor. The building defines an enclosed space, which is to be cooled. A cooling system, which includes a compressor, a condenser, and an evaporator, is provided to cool the air within the enclosed space of the building. A ground water heat transfer mechanism reduces the operating temperature of the cooling system and raises the temperature of the building floor. A heat exchange mechanism draws heat from the compressor and the condenser to reduce operating temperature of the condenser and/or compressor. The heat exchange mechanism includes a mechanism associated with an area adjacent to the building floor for maintaining that area at a temperature so that underfloor icing is prohibited. An additional objective of the system reduces the temperature of the walls and roof of the building, reducing heat loss and improving the energy efficiency of the building.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This is a continuation-in-part of U.S. patent application Ser. No. 09/611,141, filed Jul. 6, 2000. Now U.S. Pat. No. 6,484,794. 
    
    
     BACKGROUND AND SUMMARY OF THE INVENTION 
     The present invention relates to cold storage facilities and, more particularly, to energy transfer systems for maintaining the floor of a cold storage facility at a desired temperature to eliminate underfloor icing and for reducing the operating temperature of the condenser and/or compressor in the cooling system and for cooling the exterior of the building. 
     Cold storage facilities are utilized in many different industries for storing perishable items such as meat, dairy products, vegetables or the like. Some of these applications require the temperature within the facility to remain well below zero degrees Fahrenheit such as for the storage of ice cream or ice. In these facilities, it is possible that the floor, which is ordinarily concrete, may freeze. In the event the floor becomes frozen, if water or the like is underneath the floor, it is possible for the water to form into ice. This is known as underfloor icing which, as the ice expands, may cause heaving of the floor or columns, which hold the building together. 
     To alleviate underfloor icing problem, electric heating coils have been used to warm the floor to prohibit the underfloor ice. Also, some installations may utilize air ducts or pipes through which a liquid is recirculated. All of these systems require a significant amount of energy in order to provide a desired heating function to maintain the temperature under the floor at a desired level. 
     It is an object of the present invention to provide an energy transfer system which significantly reduces the energy required to maintain the fluid temperature of a circulating fluid in a piping system to prevent underfloor icing and which also reduces the energy consumption of the cooling system by lowering the condensing temperature. The present invention provides the art with an energy transfer system which utilizes the heat created by the ground, standing well, open well or body of water and the cooling system (condenser/compressor) in order to heat the fluid passed through the piping system. The present invention includes a fluid which withdraws heat from a heat exchanger in the ground prior to entering the condenser and/or compressor where a second heat exchanger also withdraws additional heat. Alternatively, water at desired temperatures can be drawn from a standing well, open well or body of water and used as the fluid. The heated fluid then passes under the floor into a piping grid to warm the space beneath the floor. Additional heating, from a source such as a gas boiler or electric heat pump, may be required to heat the fluid during periods when heat from the cooling system and ground is insufficient. 
     An additional objective of the present invention is to provide an energy transfer system which reduces the energy required during summer operation (or in a warm climate year round) to cool the building. This is accomplished by using the previously described ground heat exchanger or standing well, open well or body of water to reject heat from the fluid into the ground or water prior to entering the building walls and roof where heat gained from the ambient surroundings is absorbed by the fluid in the piping circuit passing through the walls and roof. 
     Additional objects and advantages of the present invention will become apparent from the detailed description of the preferred embodiment, and the appended claims and accompanying drawings, or may be learned by practice of the invention. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a schematic view of a cold storage facility energy transfer system in accordance with the present invention. 
       FIG. 2  is a schematic view of a piping grid for a cold storage facility. 
       FIG. 3  is an additional schematic view of a piping grid for a cold storage facility. 
       FIG. 4  is an additional schematic view of a piping grid for a cold storage facility. 
       FIG. 5  is an additional schematic view of a cold storage facility energy transfer system in accordance with the present invention with summer cooling mode. 
       FIGS. 6 and 7  are schematic views like  FIG. 1  utilizing a standing well and an open well or body of water. 
       FIGS. 8 and 9  are schematic views like  FIG. 5  utilizing a standing well and an open well or body of water. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Turning to  FIG. 1 , an energy transfer system for a cold storage facility is illustrated and designated with the reference numeral  10 . The cold storage facility  10  includes a building  12  which includes a roof  14  as well as walls  16  and a floor  18 . The walls may include a door  20  which enables access into an additional storage room  22  which acts as a loading dock. The additional storage room  22  includes a door  24  which enables access to trucks which may be loaded with the frozen material inside of the cold storage building  12 . 
     The building  12  includes a cooling system  30  which conditions the air within the building to maintain it at cold, freezing or below levels. Ordinarily, the cooling system  30  includes an evaporator  32  as well as a compressor  34  and condenser  36 . The evaporator  32  is positioned within the building. The compressor  34  and condenser  36  are located outside of the building, either adjacent in a separate building or remote from the building  12 . The compressor  34  and condenser  36  generate a substantial amount of heat due to the cooling load of the building  12 . 
     Condenser  36 , and heat source  80 , acts as a heat source for the fluid underneath the floor  18 . The fluid increases the temperature under the floor so that underfloor icing does not occur. The process of gaining heat from the condenser  36  and/or compressor  34  also has the beneficial effect of reducing the condensing temperature of the cooling system  30 . During summer operation, the ground heat exchanger  60  transfers heat from the fluid to the ground  90  to cool the fluid prior to the fluid passing through the exterior of the building  12 . 
     The ground heat exchanger  60  transfers heat to and from the ground  90  to the fluid. From the ground heat exchanger  60 , the fluid is pumped through conduit  64  by means of a pump  62  to a heat exchanger  52  which transfers heat from the condenser  36  and/or compressor  34  to the fluid. Accordingly, by withdrawing the heat, in turn, the operating temperature of the condenser  36  and/or compressor  34  is reduced. The fluid within heat exchanger  52  is then passed into a piping grid  54  which is in contact with the floor  18  of the building  12 . The piping grid  54  may have several different valves enabling the fluid to pass through different areas (zones) or under the entire floor. Also, a thermostatic control  56  is present to control the temperature of the fluid passing into the piping grid  54 . The fluid passing into the piping grid is at a desired temperature; preferably between fifty and seventy degrees Fahrenheit, to keep the area below the floor  18  free from underfloor ice. The thermostatic control  56  controls the inlet temperature to the piping grid  54  by regulating the amount of flow that can be diverted through valve  72  from the piping grid  54  if there is excess capacity and by regulating additional heating, supplied by heat source  80 , to increase the fluid temperature, if insufficient. Heat source  80  may be a boiler or heat pump, and may be required to heat the fluid during periods when heat from the cooling system and ground is insufficient, it may be located above or below ground. 
     A conduit  58  is coupled with the piping grid  54  to pass the fluid to the ground coupled heat exchanger  60 , where it again is recycled back into the heat exchanger  52 . Valve  74  allows mixing of the fluid diverted from the piping grid  54 . 
     Turning to  FIGS. 2-4 , a better understanding of the piping grid may be had. In  FIG. 2 , the piping grid  54  is illustrated underneath the floor. The conduit is coupled with the ground heat exchanger  60 . Also, a pump  62  is illustrated for pumping the fluid between the heat exchanger and the floor. Each leg of the serpentine grid  54  may include a valve for controlling fluid in the leg which, in turn, controls the temperature of that portion of the floor. 
       FIG. 3  illustrates an additional piping grid. In the piping grid illustrated in  FIG. 3 , the serpentine grid  54  is illustrated underneath the floor. Also, the ground coupled heat exchanger  60  is present to receive the fluid. A pump is present to move the fluid from the heat exchanger  60  to the heat exchanger  52  adjacent to the compressor and condenser for cooling the compressor and/or condenser. The heat through conduction is passed from the compressor and condenser assembly to the fluid which, in turn, passes it into the piping grid underneath the floor to prevent the underfloor freezing and/or icing. Also, by passing the fluid adjacent to the compressor and condenser, this reduces the temperature of the compressor and condenser, increasing the efficiency of these components. 
       FIG. 4  shows an additional embodiment. Here, the piping system not only runs under the floor, but is contained in the walls as well as in the roof. During summer (or warm climate) operation, the ground heat exchanger  60  transfers heat from the fluid to the ground  90  to reduce the temperature of the fluid. Also, the conduit may pass adjacent to the compressor and condenser and returns to the ground coupled heat exchanger. The piping grid  84  illustrated in  FIG. 4  would be utilized for summer operation. Here, the cooling effect of the ground coupling is used to reduce the compressor and condenser temperatures, and also to reduce the exterior temperature of the cold storage facility and reduce the energy required by the cooling system  30 . Both of these operations contribute to reduce energy consumption of the cold storage facility. Under these conditions, the flow of the cooling fluid in the walls and roof could be returned directly to the ground coupled heat exchanger  60 , and operate independent from the floor system. 
     The piping schemes illustrated in  FIGS. 2 and 3  are utilized in winter (or cold climate) operations. In winter, the ground coupled fluid is utilized as a heat source wherein the heat rejected by the compressor and condenser assembly is also utilized to prevent underfloor icing. Further, in the summer operation, the ground heat exchanger acts as a heat sink, providing a cooling fluid to reduce the compressor and/or condenser pressures, as well as their temperature, and likewise the cooling fluid is passed around the walls and ceiling which reduces the temperature in the walls and ceiling and thereby the heat loss through the walls and ceiling which, in turn, enables less cooling to be used to maintain a given building temperature. 
     Accordingly, fluid is pumped from the ground heat exchanger  60  into the heat exchanger  52 . Thermostatic control  56  regulates flow to the piping grid  54  to maintain the desired temperature. The temperature of fluid in the heat exchanger  52  increases as heat is transferred from the compressor and condenser into the fluid. This heated fluid, still under pressure of the pump, then passes into the piping grid  54  in contact with the floor  18  of the building  12 . At that time, the space or area beneath the floor  18  is heated to maintain a temperature prohibiting ice formation underneath or on the floor. The fluid continues into the ground heat exchanger  60  where it is again recycled back into the heat exchanger  52 . 
     By utilizing the heat generated by the compressor and the condenser, the present system reduces the energy consumption required to heat the area underneath the floor to prohibit underfloor icing. This system reduces energy consumption since the fluid is heated by both the ground and the compressor and condenser and the only power required to run the system is that need to run the pump or pumps to circulate fluid throughout the system. In addition, energy consumption of the cooling system is also reduced by lowering the condensing temperature. 
       FIG. 5  illustrates an additional embodiment of the invention with like elements identified with the same reference numerals. During summer operation, the ground heat exchanger  60  transfers heat from the fluid to the subsurface ground or a body of water  90  to reduce the temperature of the fluid. From the ground heat exchanger  60 , the fluid is pumped via conduit  82  throughout piping grid  84  located in the walls and roof of building  12  to cool the exterior of the building  12  to reduce the energy required by the cooling system  30  and the heat loss through the building walls and roof. From piping grid  84 , the fluid passes through valve  86  by way of conduit  88  where it is mixed with any fluid from conduit  64 . The fluid then cools the compressor and condenser and either returns directly to the ground coupled heat exchanger or the fluid then flows through the circuit to heat the floor  18 , as required, in like manner as previously described. 
     By utilizing the heat generated by the ground  90 , condenser  36  and/or compressor  34 , and heat source, the present system reduces the energy consumption required to heat the area underneath the floor  18  to prohibit underfloor icing. In addition, energy consumption of the cooling system  30  is also reduced by lowering the condensing temperature. In addition, the system may be used to cool the exterior of the building  12  during summer operation or year-round in a warm or hot climate. 
       FIGS. 6 and 7  illustrate additional embodiments on the present invention. Like elements are identified with the same reference numerals. 
     In  FIG. 6 , a standing well is illustrated and designated with the reference numeral  94 . The standing well  94  is drilled into the ground to provide a water source. Water is drawn by pump  62  via conduit  64  into the system. The conduit  64  is positioned deep inside the standing well so that the water drawn into the system is at a desired temperature of the ground at a lower level. Water returns to the well via conduit  58  and is deposited onto the surface of the well. Thus, this illustrates that a standing well may be utilized having a continuous supply of groundwater entering into the well  94 . 
     Turning to  FIG. 7 , an open well or body of water is designated with the reference numeral  96 . Here, the conduit  64  would be positioned into the open well or body of water  96  and the pump  62  would draw the water into the system. Likewise, conduit  58  would deposit the water back into the open well or body of water  96 . The embodiments in  FIGS. 6 and 7  enable the use of groundwater in the system when the sources of groundwater are readily available. 
       FIGS. 8 and 9  illustrate embodiments of the invention like those illustrated in FIG.  5 . In  FIG. 8 , a standing well  94  is provided. The standing well  94  is like that described above and can be utilized in the present invention. 
       FIG. 9  illustrates an embodiment utilizing an open well or body of water  96 . As mentioned above, though water is drawn into the system and is exited into the body of water. 
     Accordingly, where ground or well water is readily available, the present invention can utilize these water sources directly for the fluid utilized in the system. Also, the water is continuously refreshened and circulated into the system keeping a desired temperature to dissipate or transfer heat to the area below the floor or into the walls and roof of the building. 
     While the above detailed description describes the preferred embodiment of the present invention, the invention is susceptible to modification, variation, and alteration without deviating from the scope and fair meaning of the subjoined claims.