US20090032215A1 - Water tank for use with a solar air conditioning system - Google Patents

Abstract

A water tank for use in air-conditioning and/or heating systems and includes a container capable of storing at least one thousand gallons of a fluid. An evaporator coil is disposed within the container and the fluid contained within the container. The evaporator can consist as part of a refrigerant circuit. A pickup radiator coil is also disposed within the container and fluid. The pickup radiator coil can consist as part of a chilled water air conditioning water system for a dwelling. The water tank can be insulated. The fluid stored within said container can be a mixture of water and anti-freeze.

Description

• This application is a continuation of U.S. application Ser. No. 12/249,071, filed Oct. 10, 2008, which is a continuation-in-part of U.S. application Ser. No. 11/671,547, filed Feb. 6, 2007, which claims the benefit of and priority to U.S. Application Ser. No. 60/853,531, filed Oct. 23, 2006. All applications are incorporated by reference in their entireties as if fully set forth herein.
1. FIELD OF THE INVENTION
• The present invention relates generally to air conditioning systems and particularly to a solar air conditioning system.
2. BACKGROUND OF THE INVENTION
• High electricity bills from air conditioning and/or heating use for a dwelling are common and reoccurring. Additionally, the manufacture of energy at a power plant causes pollution to be released in the air. Furthermore, electricity availability in undeveloped countries, as well as remote locations in developed countries, may be scarce, on limited basis or often non-existent. As a result, these locations are unable to store foods and liquids requiring refrigeration due to the lack of electricity. For undeveloped countries the lack of electricity is a factor in the poverty, hunger and lack of nourishment for its citizens. It is to these problems that the present invention is directed.
SUMMARY OF THE INVENTION
• The present invention generally provide a solar air-conditioning system that is preferably designed to operate with concentrated solar heat supplemented with solar electric cells/battery and if necessary, power from an electric utility grid. The unit of heat added or subtracted is a British Thermal Unit (“BTU”), which is defined as the amount of heat to raise one pound of water one (1°) degree Fahrenheit. With excess capacity preferably designed in, unused BTUs can go into reserve for night and cloudy days. The present invention system can use a circulating refrigerant such as, but not limited to, Freon or ammonia in a cycle of compression and expansion. Solar concentrators can raise temperature and pressure of the refrigerant. The raised temperature can be dissipated to the atmosphere and the refrigerant proceeds to the evaporator coil. The evaporator can be located within a water tank containing an anti-freeze water solution. Preferably, the water tank contains at least approximately 1000 gallons of the anti-freeze water solution. The water is preferably the storage medium. Heat can be added to or extracted from the storage medium by the evaporator coil.
• Preferably, also within the water tank can be a radiator type pickup coil. The pickup coil can be part of a separate chilled water system which can circulate its own water supply through radiators located throughout a building, dwelling, house, etc. (all collectively referred to as “dwelling”). The temperature within this separate system can be the temperature of the water within the tank by simple conduction.
• The refrigerant system can include a supplemental compressor which can be electrically driven from one or more, and preferably a plurality or bank of, solar electric cells or the power grid. The refrigerant system can also include one way direction positive displacement rotary valves which can serve to insure proper gas direction and can also provide a mechanical link to the energy in the refrigerant circuit. This mechanical link can be used to power a generator or a fluid pump. When in solar heat mode, certain bypass valves within the refrigerant system allow switching to solar heating. When in this mode the generator may be electrically switched to function as a motor to assist the circulation of the refrigerant.
• The present invention can also be used for or applicable to large area coolers or refrigerators and provides a device which can provide refrigeration to areas where electricity is not present or available.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a schematic/flow diagram of a first embodiment for the present invention system;
• FIG. 2 is schematic/flow diagram of a portion of a second embodiment for the present invention system;
• FIG. 3 is schematic/flow diagram of a portion of a third embodiment for the present invention system;
• FIG. 4 is a detailed view of one bypass valve (which is used when switching to solar heat mode) that can be used in accordance with the present invention system;
• FIG. 5 is a schematic of a first embodiment for an expansion valve that can be used in accordance with the present invention system;
• FIG. 6 is a schematic of a second embodiment for the expansion valve in accordance with the present invention system;
• FIG. 7 is a schematic of a third embodiment for the expansion valve in accordance with the present invention system;
• FIG. 8 is a diagram for allowing a condenser coil of the present invention system to dissipate heat to water circulated over its surface;
• FIG. 9 is a perspective view of a solar concentrator which can be used with the present invention system;
• FIG. 10 is a perspective view of rotary valve that can be used with the present invention system;
• FIG. 11 is a perspective view of the inner cylinder for the rotary valve ofFIG. 10;
• FIGS. 12 through 16 illustrated alternative concentrators that can be used with the present invention system; and
• FIG. 17 illustrates a schematic/flow diagram of another embodiment for the present invention system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
• As seen best inFIG. 1 a solar air-conditioning system is illustrated and generally referenced assystem10.System10 includes one or moresolar concentrators20 and preferably a plurality ofconcentrators20 preferably arranged in a parallel configuration or communication with each other. Concentrator(s)20 capture energy from the sun raising the temperature and pressure of the refrigerant within the pipe, tubing, plumbing, conduits, hoses, etc. (all collectively referred to as “pipe” or “piping”) at the focal point. Though not considered limiting, the refrigerant can be Freon or ammonia gas. All of the pipe, valves, components, etc. of the present invention are preferably connected to each other through conventional connectors, fasteners, etc.
• The refrigerant within the pipe proceeds or otherwise travels to the one or more heat dissipaters, commonly known ascondensers30, which can be large area condensers. The number ofcondensers30 can correspond to the number of concentrators provided forsystem10.Condensers30 dissipate heat from the heated refrigerant to the atmosphere. In one embodiment,condenser30 can be approximately the size of itscorresponding concentrator20 in length and width and affixed toconcentrator20 with a spacing measurement betweenconcentrator20 and condenser30 preferably within twelve (12″) inches of each other. However such spacing measurement is not considered limited to within twelve (12″) inches and other values can be used and are considered within the scope of the invention.
• In an alternative embodiment,condenser30 can be a single stand alone unit, which can include an electrically driven fan similar to conventional condensers. Thus,FIG. 1 illustrates multiple condensers, whereasFIG. 3 illustrates asingle condenser coil260.
• After leaving condenser(s)30, the refrigerant proceeds through a onedirection valve40. In a preferred embodiment, the one direction valve can be a “high side” positive displacement one direction rotary valve.Valve40 assures that the refrigerant proceeds in the proper direction through the refrigerant circuit. As shown inFIG. 1, in one embodiment, a plurality of vanes are provided within the valve housing, which are moved by the circulating refrigerant (a portion of the refrigerant within the valve is shown in shading/hatched lines between two of the vanes).Valve40 can also provide amechanical link60 to the energy produced by the moving refrigerant. The mechanical link can be used to drive a generator, water circulation pump and/or other device.
• Fromvalve40, the refrigerant travels to anevaporator80 which is preferably fitted with anexpansion valve90. In the preferred embodiment,expansion valve90 can be an electronically controlled valve, though such is not considered limiting.FIGS. 5 through 7 provides further details on various non-limiting expansion valve embodiments that can be used with the present invention system or circuit.
• Valve90 is controlled based on the pressures contained within the refrigerant circuit which can vary as the solar energy varies. The expanding refrigerant withinevaporator80 removes the heat from the coil andmedium surrounding evaporator80. Preferably,evaporator80 can be disposed within awater tank100.Water tank100 is preferably large enough in size to hold a large amount of a liquid, such as, but not limited to, approximately two thousand (2000) gallons of the liquid. However, other size water tanks can be used and are considered within the scope of the invention.
• Preferably, the liquid106 contained withinwater tank100 can be a mixture of water and anti-freeze. Preferably,water tank100 can be insulated, such as, but not limited to, buryingwater tank100 beneath ground level. Additionally,water tank100 can be greater in height than width to operate co-operatively with temperature stratification. As such, heat can be removed from many gallons of water, which a non-limiting example is shown by the following factoid using a non-limiting 2000 gallon water tank100:
• British Thermal Unit (‘BTU’). 1 BTU=1 pound of water 1° F.
• Water=8 pounds per gallon; 1 cubic foot=7.48 gallons=60 pounds of water.
• 134 cubic feet—8018 pounds of water.
• Non-limiting Tank 100 dimensions: 4.2 ft×8 ft×8 ft=269 cu. ft=2000 gallons
• 2000 gallons=16,000 pounds=16,000 BTU per degree Fahrenheit.
• 32° F. to 12° F.=20° F.
• 20° F.×16,000 BTU=320,000 BTU
• 320,000 BTU/20,000 BTU hour=16 hours reserve.
• Solar Power:
• 200 BTU/square foot/hour around solar noon.
• 20,000 BTU's per 100 square feet
• 40,000 BTU's per 200 square feet
• Non-limiting Solar Concentrator 20 dimensions: each 2 ft.×10 ft.=20 square ft
• 10 units=200 square ft=40,000 BTU/hour
• The refrigerant exits fromevaporator80 and is directed to a second onedirectional valve110, which again can be a positive displacement one direction rotary valve.Valve110 can have a larger positive displacement chamber as compared tovalve40 since it may be working with lower pressures, and thus in the preferred embodiment, can be considered a low pressure valve.Valve110 can also have amechanical link62 and can be (though not required) mechanically linked withvalve40, as illustrated inFIG. 1. By linkingvalves40 and110 together, stability can be provided to the refrigerant circuit. Furthermore, the rotation ofvalves40 and110 can derive rotational mechanical energy which can be utilized to drive a generator, water circulation pump, etc. and is illustrated with a generator orwater pump112. The vanes ofvalves40 and110 can be spring loaded.
• The refrigerant then is directed fromvalve110 to a preferably commonly connected balancingvalve120 and/or as an inlet tocompressor140.System balancing valve120 can have afirst inlet valve122 which can constitute the primary circuit for the refrigerant and asecond inlet valve124 which is in communication with the outlet ofcompressor140. Refrigerant travels through balancingvalve120 to one direction or one-way valve150 where it proceeds to solar concentrator(s)20 to restart the cycle.
• Compressor140 can be driven by aconventional compressor motor144. Thus, when there is insufficient solar energy (cloudy day, etc.), system10 (such as through one or more sensors provided in the circuit) can sense or otherwise determine to activatemotor144 to electrically drivecompressor140. In one non-limiting example, a temperature sensor can be disposed within the water tank for determining when to turnmotor144 on. Additionally, pressure sensors or other devices can also be used for this purpose. Pressurized refrigerant fromcompressor140 can proceed throughsecond inlet valve124 on the balancing valve to onedirection valve150. Where a temperature sensor is provided withinwater tank100,compressor140 can be activated at predetermine temperatures through its connection to a conventional switcher (not shown inFIG. 1 but can be similar to the switch control shown inFIG. 2). In one non-limiting example, the predetermined temperature can be anywhere in the range of about 32° F. to about 12° F. However, other temperature values can be used and are considered within the scope of the invention.
• The present invention can store air conditioning energy in the form of chilled water, which can be below the freezing point of 32° F., and preferably within the temperature range of 32° F. to 12° F. or about 32° F. to about 12° F. However, the present invention is not limited to this specific range and other ranges can be chosen and are within the scope of the invention.
• Balancingvalve120 can be constructed such that there is linkage betweenfirst inlet valve122 andsecond inlet valve124. Thus,first inlet valve122 can be closed, when the force of the pressurized refrigerant fromcompressor140 openssecond inlet valve124. Similarly, whenfirst inlet valve122 is opened through receipt of refrigerant fromvalve110,second inlet valve124 can be closed. It is also possible and within the scope of the invention that bothfirst inlet valve122 andsecond inlet valve124 are partially opened at the same time and the refrigerant traveling through both inlet valves (122 and124) merges or combines and enters a single outlet which serves as the inlet to oneway valve150.
• As seen inFIG. 1,water tank100 also contains apickup radiator180 acting as heat exchange coil which functions as part of a separate chilled (or heated)water system175 of air-conditioning (heat) for withdrawing (or adding) heat from (or to) a dwelling or structure through one ormore radiators190.Pickup radiator180 inwater tank100 and onemore radiators190 disposed throughout the dwelling can circulate anti-freeze/water by way of apump196, which can be electrically or mechanically driven. The circulation of the water allows heat to be removed from or added to (as desired) from the dwelling. The chilled (heated) liquid or water system in the preferred embodiment is separate and isolated from the storage medium liquid or water. One skilled in the art would include a control, such as a thermostatic control, at each dwelling coil controlling the cold water flow such that the freezing point is not attained in these coils.
• The present invention system can also be converted or otherwise switch from solar air conditioner to solar heating. As seen inFIG. 2,system250, which can contain similar not shown components assystem10, where a stand-alone (single) condenser260 (FIG. 3) is used a bypass valve270 (with associated pipe) can be provided atcondenser260. It should be recognized that multiple condensers, such as shown inFIG. 1, can also be used and each condenser can be provided with a bypass valve and associated pipe. By opening or otherwise engagingbypass valve270 and electrically withdrawing the controlling element of theelectronic expansion valve90, the solar heated refrigerant is allowed to circulate throughevaporator80, which heats the water or mixture inwater tank100 by conduction.Generator190, which can be commonly connected torotary valves40 and/or110 can be electrically switched to function as a motor. The motor can driverotary valves40 and/or110 to assure circulation of the heated refrigerant through the refrigerant circuit.
• Bypass valve270 is shown in more detail inFIG. 4. Ahousing271 withinlet port273 andoutlet port275 is shown.Actuator solenoid277 controlling apiston279 dictates the travel route of the refrigerant by opening or closing appropriate ports depending if the system is being used for air conditioning or for heating purposes. However, other types of bypass valves can be used with the present invention system or circuit and are also considered within the scope of the invention.
• As the heat of the refrigerant has not been dissipated through a condenser, the refrigerant warms water or mixture intank100, which in turn causes the liquid/water inpickup radiator180 to be heated and then dispersed throughsystem175 bypump196 as described above.
• As seen inFIG. 2, the present invention system can also be complemented with solarelectric panels300 andbattery320. Electricity derived from this sub-system can drivecompressor140. The energy from concentrator(s)20 and the solar electric can compliment each other to drive the refrigerant within the circuit. Additionally, at times of insufficient solar energy or battery energy, power from autility grid370 can supply the energy to drivecompressor140. A switchingcontrol324 can be provided for managing or controlling the various energy sources. Thus, the various components help to drivecompressor140 when needed, which can be considered, though not required, a supplement mode of energy.
• It should be recognized that various combinations of concentrator(s), battery(ies), utility grid (conventional electricity), solar panel(s), etc. can be used and all combinations are considered within the scope of the invention. Thus, as non-limiting examples, the complimentary system does not necessarily preclude (1) a system which operates solely on energy from solar concentrators, excluding solar electric; or (2) a system which operates solely on solar electric panels, excluding solar concentrators. Again, the above-described energy sources can be used in various combinations or by themselves and all variations are considered within the scope of the invention.
• FIGS. 5 through 7 illustrate several embodiments for the expansion valve component of the present invention. The primary function of the expansion valve is to meter pressurized gas (high side) into the evaporator (low side) allowing expansion of the gas and corresponding heat absorption. Conventional expansion valves operate with a constant known pressure. However, with the present invention system it is preferred that the expansion valve operate over a range of pressures as solar energy will vary. Thus, different types of novel designs for the expansion valve can be used and incorporated into the present invention system where the expansion valve can be controlled according to pressures on the high side and on the low side within the refrigerant circuit.
• As seen inFIG. 5, anexpansion valve110 is shown and can be controlled by sensing refrigerant which has been compressed to a liquid state, and acting at that point to control the expansion valve to open slightly to allow a greater flow and thus reducing the pressure in the evaporator.
• As seen inFIG. 6, anexpansion valve200 is shown and can have apressure sensing diaphragm202 connected to acontrol element203 ofexpansion valve200. The active chamber of thediaphragm202 can be connected toevaporator80, such as, but not limited to, through a suitable conduit (i.e. pipe204).Diaphragm202 can be connected to controlelement203 through aleverage bar205 and aspring206.Spring206 has increasing tension with compression. In operation, as gas pressure in thehigh side207 of the refrigerant circuit rises,valve control element203 is raised and thus overcoming the spring tension and allowing passage of the refrigerant. As pressures begin to rise in the evaporator,diaphragm202 moves to closecontrol element203 and thus blocks or limits passage of the refrigerant. As such,control element203 meters the flow of gas according to the pressure in the evaporator. With even higher pressures diaphragm202 limit will be reached and spring tension will maintain the restrictive pressure onvalve control element203.Spring206 can be gradually increasing pressure with compression.
• As seen inFIG. 7, anexpansion valve350 is shown and controls itscontrol element203 through the use of an electrically drivelinear motor301. Control ofvalve element203 is again according to pressures within the refrigerant circuit and particularly on the high side beforeexpansion valve300 and after the valve withinevaporator80.Valve300 can include an electrical potentiometer combined with a mechanical pressure sensor and is shown inFIG. 7 as apressure diaphragm302 with associatedpotentiometer303. As the circuit ofFIG. 7 reacts to changing pressure the wiper/arrow moves along the resistive element of the potentiometer to vary the resistance.
• Though in the preferred embodiment the chilled water system can be an isolated closed system with a pickup coil in the water tank, such is not considered limiting. It is also within the scope of the invention to have the present invention operate with no pickup coil within the tank. Such an alternative version could operate circulating the storage medium water within the water through the in-dwelling radiators.
• FIGS. 10 and 11 illustrates arotary valve400 that can be used with the present invention system as such asvalve40 and/orvalve110 shown inFIG. 1.Valve400 comprises an outer cylindricalvalve body housing402 having aninlet port404 and anoutlet port406. Preferably,outlet port406 can be preferably at least one-hundred (100°) degrees in direction of rotation frominlet port404 in a four (4) vane configuration and correspondingly so with multiple vanes. An inner rotational cylinder420 is disposed withinhousing402 and can be supported by a centerlongitudinal shaft422 offset from the center ofouter housing402. A plurality of vanes424 (preferably spring loaded) are fitted into cylinder420. Vanes424 are disposed along the longitudinal axis of cylinder420 and preferably equally spaced from each other around the circumference of cylinder420. As seen in theFIG. 10, innercylinder support shaft422 can extend beyondvalve housing402 such that external appliances can be attached thereto. A portion of cylinder420 is flush against the inner wall ofhousing402 such thatvane424ais fully compressed. As a gap is created between the portion of cylinder420 associated withvane424bandhousing402,vane424bprotrudes outward from cylinder420, in view of its preferred spring loaded configuration.
• Fundamental to the “refrigeration” or “heat pump” cycle is a dissipation of the heat of compression. This is usually accomplished by circulating the compressed refrigerant gas through a finned coil exposed to the atmosphere (i.e. a condenser coil). It may be a large area condenser to dissipate heat by simple conduction (FIG. 1, #30) or it may be smaller and compact with fan forced air circulation (FIG. 3).
• Another embodiment or method that can be used with the present invention system is illustrated inFIG. 8. In this method,condenser coil30 may dissipate heat to water circulated over its surface. The water can be drawn by a pump from an underground water table. The underground water temperature can be approximately twenty-five (25° F.) degrees Fahrenheit cooler than the atmosphere. Other degree differences can also be selected and are considered within the scope of the invention. Thus, the efficiency of the heat dissipation and of the overall cooling is enhanced. This method might circulate water from the water table. Alternatively, water can be sprayed as a mist onto the condenser in its own external evaporation cycle of liquid to gas.
• It should be recognized that other concentrators can be used with the present invention system and all are considered within the scope of the invention. Certain examples of concentrators are generally shown in the Figures but are not considered to limit the types of concentrators that can be used and incorporated into the present invention system.
• FIG. 12 is a perspective view of adish concentrator500 that can be used with the present invention system.FIG. 13 is a partial cutaway perspective view of a ceramiccoil pickup unit502 ofdish concentrator500 illustrating the internal ceramic spiral coil.FIG. 14 is a perspective view of a solar receiver and heat-engine housing collectively referenced atnumeral520.FIG. 15 illustrated aparabolic trough concentrator530 andFIG. 16 illustrates aFresnel lens concentrator540.
• The above-described and illustrated rotary positive displacement valves provide a unique valve design which can be advantageously optimized for the instant invention system. The movement under pressure of a gas or liquid, such as, but not limited to, a refrigerant in liquid or gas form, causes the rotation of the valve. Preferably composed of four chambers in a four vane version, each vane chamber successively is filled and caused to rotate by the high side pressure on that chamber vane. The chamber is then closed by the following vane and finally emptied as such chamber is decreased in volume due to the preferred offset center, the point of co-incidence of the inner cylinder rotor and the vane and placement of the exit port. The valves of the present invention are driven by the pressure of the heated gas. Preferably, two valves are connected together, with the high side and the low side all given stability to the refrigerant movement through the circuit. In solar heat mode, the valves may be motor driven to promote circulation of the heated refrigerant. The valves do not compress in either the solar air conditioning mode or the solar heat mode.
• Thus in one embodiment, a rotational multi-vane positive displacement valve is disclosed which can comprise: an outer cylindrical valve body housing having an inlet port and an outlet port and an inner rotational cylinder disposed within the outer cylindrical valve body housing and supported by a longitudinal shaft offset from a center position of the outer housing. The inner rotational cylinder can have a plurality of spring loaded vanes along a substantial portion of its longitudinal axis that are preferably equally spaced around a circumference of the inner rotational cylinder. The outlet port can be located at least 100 degrees in direction of rotation from the inlet port, when the inner cylinder has four vanes. The shaft preferably extends beyond the outer valve housing and can be adapted for attachment to external appliances.
• Thus, summarizing the present invention provides a solar air-conditioning system that is preferably designed to operate with concentrated solar heat and uses a circulating refrigerant in a cycle of compression and expansion. Solar concentrators raise the temperature and pressure of the refrigerant. The raised temperature is dissipated to the atmosphere and the refrigerant proceeds to the evaporator coil, which is located within a water tank containing at least 1000 gallons of an anti-freeze water solution. As the water is the storage medium, heat can be added to or extracted from the storage medium by the evaporator coil. A radiator pickup coil is also located within the water tank and is part of a separate chilled water system which can circulate its own water supply through other radiators located throughout a dwelling. Additionally, one or more bypass valve(s) within the refrigerant system allow switching to solar heating.
• The above-described systems of the present invention can also be used for or applicable to large area coolers or refrigerators and provides a device which can provide refrigeration to areas where electricity is not present or available.
• While the invention has been described and disclosed in certain terms and has disclosed certain embodiments or modifications, persons skilled in the art who have acquainted themselves with the invention, will appreciate that it is not necessarily limited by such terms, nor to the specific embodiments and modifications disclosed herein. Thus, a wide variety of alternatives, suggested by the teachings herein, can be practiced without departing from the spirit of the invention, and rights to such alternatives are particularly reserved and considered within the scope of the invention.

Claims (10)

1. A water tank for use in air-conditioning or heating system, comprising:

a container storing at least one thousand gallons of a fluid;

an evaporator coil disposed within the container and fluid, said evaporator consisting as part of a refrigerant circuit; and

a pickup radiator coil disposed within the container and fluid, said pickup radiator coil consisting as part of a chilled water air conditioning water system for a dwelling.

2. The water tank ofclaim 1 wherein said container is insulated.

3. The water tank ofclaim 1 wherein said fluid stored within said container is a mixture of water and anti-freeze.

4. The water tank ofclaim 2, wherein said container is insulated by burying the container beneath ground level.

5. The water tank ofclaim 1 wherein said container is greater in height than width.

6. The water tank ofclaim 1 wherein said container storing about 2000 gallons of fluid.

7. A water tank for use in air-conditioning or heating system, comprising:

an insulated container storing at least one thousand gallons of a fluid comprised of a mixture of water and anti-freeze, said container greater in height than width;

an evaporator coil disposed within the container and fluid, said evaporator consisting as part of a refrigerant circuit; and

a pickup radiator coil disposed within the container and fluid, said pickup radiator coil consisting as part of a chilled water air conditioning water system for a dwelling.

8. The water tank ofclaim 7, wherein said container is insulated by burying the container beneath ground level.

9. The water tank ofclaim 1 wherein said container storing about 2000 gallons of the fluid.

10. A water tank for use in air-conditioning or heating system, comprising:

a container storing about two thousand gallons of a fluid comprised of a mixture of water and anti-freeze, said container greater in height than width, said container buried beneath ground level for insulating purposes;

an evaporator coil disposed within the container and fluid, said evaporator consisting as part of a refrigerant circuit; and

a pickup radiator coil disposed within the container and fluid, said pickup radiator coil consisting as part of a chilled water air conditioning water system for a dwelling.

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