HEAT PUMP WITH INTGERAL SOLAR COLLECTOR

The present invention generally relates to heat pumps that utilize at least one thermal source operating with the same working fluids. In one embodiment, the present invention relates to a hybrid solar heat pump comprised of at least one microchannel heat exchanger with integral solar absorber, at least one compression (i.e., mass flow regulator) device as the heat pump for concurrent compression to a higher pressure and mass flow regulator of the working fluid, and at least one working fluid accumulator with the entire system operating with the same working fluid. The present invention also generally relates to heat pump systems that utilize an inventory management system to provide both efficient and safe operation under a wide range of operating conditions.

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Description
CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. Patent Application Ser. No. 61,231,674 filed Aug. 6, 2009, having the title “Solar collector with expandable fluid mass management system” and U.S. Patent Application Ser. No. 61,231,238 filed Aug. 4, 2009, having the title “Heat Pump with Integral Solar Collector” and included as reference only without priority claims. Numerous additions have been made since the filing of the provisional patent applications cited earlier. These include FIGS. 9-14, and FIG. 17. The combining of the two provisional filings have lead to some of the original figures being renumbered to maintain like numerals for like components.

FIELD OF THE INVENTION

The present invention generally relates to a heat pump system having a highly integrated mass management system and external heat source to increase operating efficiency and reduce capital cost. In all embodiments, the present invention utilizes the same working fluid within all thermodynamic cycles, and the present invention utilizes gravity to discharge a relatively cooler and more dense fluid as displaced by a volumetrically equivalent relatively warmer and less dense fluid.

BACKGROUND OF THE INVENTION

Due to a variety of factors including, but not limited to, global warming issues, fossil fuel availability and environmental impacts, crude oil price and availability issues, alternative energy sources are becoming more popular today. One such source of alternative and/or renewable energy is solar energy. One such way to collect solar energy is to use a solar receiver to focus and convert solar energy into a desired form (e.g., thermal energy or electrical energy). Thermal energy harvested from the sun is known in the art to be utilized in absorption heat pumps, domestic hot water and industrial processes, power generating cycles through the heating of a secondary heat transfer fluid, power generating cycles through the direct heating of power generating working fluid such as steam, and for heating. Furthermore, it is recognized that a wide range of energy consumers can be supplied via electrical and/or thermal energy such as air conditioning, refrigeration, heating, industrial processes, and domestic hot water. Given this, solar collectors that function in efficient manners are desirable.

Traditional thermal activated processes effectively consider every unit of energy into the system. Furthermore by definition solar energy is a function of solar intensity and thus at the minimum is absent during the nighttime, unless significant thermal storage is utilized that is currently very expensive. Additionally, it recognized in the art that vapor compressor heat pumps have coefficients of performance “COP” substantially higher than absorption heat pumps. And hot water heaters utilizing vapor compressor driven heat pumps also have substantially higher COPs as compared to direct heating of hot water having COPs less than unity. In addition, traditional solar collectors, particularly flat panel collectors, are temperature constrained due in large part to declining efficiencies as a function of temperature and the degradation of the working fluid which is often a mixture of a glycol and water. Solar collectors typically fall into the category of pump driven working fluid circulation or thermosiphon that respectively have the deficiency of requiring a pump or orientation of solar collector with respect to the “condenser”.

Heat pumps also have significant limitations that limit temperature including the requirement for oil lubrication that would suffer oxidative destruction at the higher temperatures desired within heat pumps. Additionally, the working fluid in virtually all refrigerants is significantly expandable across a wide operating temperature range.

The combined limitations of each individual component being the solar collector and the heat pump presents significant challenges that are further exasperated when high integration using the same working fluid for both devices is realized.

Traditional solar systems utilize a non-expandable working fluid under pressures less than 50 psia, or working fluids having expandability ratios between the cold and hot temperatures of less than 3. The traditional solar systems utilize a working fluid that is a heat transfer fluid and thus isn't directly compatible as a thermodynamic cycle working fluid. As noted, the density of the working fluid by being expandable changes by an order of magnitude as a function of operating pressure and temperature. Furthermore by definition solar energy is a function of solar intensity and thus at the minimum is absent during the nighttime, unless significant thermal storage is utilized that is currently very expensive, the system will experience substantial changes in density according to operating and ambient conditions.

SUMMARY OF THE INVENTION

The present invention is directed to the use of expandable fluids for thermally activated processes. The expandable fluid when heated has decreasing density given the same pressure, and increasing the pressure creates heat of compression. The heat of compression is realized in the art through the operation of a heat pump. The further coupling of heat the expandable fluid using either solar energy or other externally combusted fuels enables a significant reduction of capital cost thus lowering the levelized cost of energy, whether that energy be in the form of thermal or electricity/mechanical energy. The change in density further enables one power consuming device, which is a heat pump operable as a turbocompressor, turbopump, or other configurations of generally recognized compressors to perform a secondary function of regulating the inventory of working fluid within the thermodynamic cycle that the heat pump operates within.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sequential flow diagram of one embodiment having multiple configurations of an integrated solar collector and heat pump in accordance with the present invention;

FIG. 2 is a sequential flow diagram of one embodiment of an integrated solar collector and heat pump having a supplemental fluid accumulator in accordance with the present invention;

FIG. 3 is a sequential flow diagram of one embodiment of an integrated solar collector and heat pump having multiple thermal sinks in accordance with the present invention;

FIG. 4 is a sequential flow diagram of one embodiment of an integrated solar collector and heat pump operating as a radiant cooler in accordance with the present invention;

FIG. 5 is a sequential flow diagram of one embodiment of an integrated solar collector switchable as a thermal source or sink, and heat pump in accordance with the present invention;

FIG. 6 is a sequential flow diagram of one embodiment of an integrated solar collector and heat pump with an integrated desiccant dehumidifier in accordance with the present invention;

FIG. 7 is a sequential flow diagram of one embodiment of an integrated solar collector and heat pump with an integrated power generating expander in accordance with the present invention;

FIG. 8 is a sequential flow diagram of one embodiment of an integrated solar collector and heat pump having multiple thermal sinks and an integrated photovoltaic cell in accordance with the present invention;

FIG. 9 is a sequential flow diagram of one embodiment of an integrated solar collector and heat pump configured as a domestic hot water system in accordance with the present invention;

FIG. 10 is a sequential flow diagram of one embodiment of an integrated solar collector with external combustion to superheat working fluid and heat pump configured as a cooling system in accordance with the present invention;

FIG. 11 is a sequential flow diagram of one embodiment of an integrated solar collector and heat pump configured with solar collector as a preheat stage of external combustion stage in accordance with the present invention;

FIG. 12 is a sequential flow diagram of one embodiment of an integrated solar collector and heat pump configured with solar collector as a superheat stage of external combustion exhaust gases and heat pump heat of compression stages in accordance with the present invention;

FIG. 13 is a sequential flow diagram of one embodiment of an integrated power generation cycle with a heat pump cycle powered by power generation cycle configured for cooling in accordance with the present invention;

FIG. 14 is a sequential flow diagram of one embodiment of an integrated power generation cycle with a heat pump cycle powered by power generation cycle configured for cooling, and a working fluid inventory management system in accordance with the present invention;

FIG. 15 is a sequential flow diagram of one embodiment of an integrated solar collector and inventory mass management system operating with a mechanically driven pressure generating device in accordance with the present invention;

FIG. 16 is a sequential flow diagram of one embodiment of an integrated solar collector and inventory mass management system operating in a hybrid thermosyphon approach in accordance with the present invention; and

FIG. 17 is a sequential flow diagram of one embodiment of an integrated solar collector and inventory mass management system operating with a series of individually operated fluid circuit branches in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The term “non-linear”, as used herein, includes any surface of a solar receiver whose surface shape is described by a set of nonlinear equations.

The term “microchannel”, as used herein, includes channel dimensions of less than 2.5 millimeters.

The term “reflector”, as used herein, includes a surface or surface coating that reflects greater than 50% of at least one portion of the incoming light spectrum, which includes the portions of visible, infrared, and ultraviolet.

The term “in thermal continuity” or “thermal communication”, as used herein, includes the direct connection between the heat source and the heat sink whether or not a thermal interface material is used.

The term “multipass”, “multi-pass”, or “multiple passes”, as used herein, includes a fluid flow into at least one portion of a heat exchanger and out of at least one other portion of a heat exchanger wherein the at least one portion of the heat exchanger and the at least one other portion of a heat exchanger can either be thermally isolated from each other or in thermal continuity with each other.

The term “boiler”, as used herein, includes a heat exchanger transferring thermal energy into a working fluid wherein the working fluid is comprised of at least 5% vapor phase.

The term “superheater”, as used herein, includes a heat exchanger transferring thermal energy into a working fluid wherein the heat exchanger is used to convert saturated steam into dry steam.

The term “fluid inlet” or “fluid inlet header”, as used herein, includes the portion of a heat exchanger where the fluid flows into the heat exchanger.

The term “fluid discharge”, as used herein, includes the portion of a heat exchanger where the fluid exits the heat exchanger.

The term “expandable fluid”, as used herein, includes the all fluids that have a decreasing density at increasing temperature at a specific pressure of at least a 0.1% decrease in density per degree C.

The term “heat transfer fluid” is a liquid medium utilized to convey thermal energy from one location to another. The terms heat transfer fluid, working fluid, and expandable fluid are used interchangeably.

The present invention generally relates to a solar collect system having an integral working fluid management system that enables the system to increase or decrease the mass of the working fluid within the circulation loop of the closed loop system. The present invention also generally relates to a heat pump system having an integral solar collector that utilizes one working fluid in common between the two elements.

Here, as well as elsewhere in the specification and claims, individual numerical values and/or individual range limits can be combined to form non-disclosed ranges.

The heat transfer fluid within the embodiments is preferably a supercritical fluid as a means to reduce the pressure drop within the heat exchanger. The supercritical fluid includes fluids selected from the group of organic refrigerants (R134, R245, pentane, butane), gases (CO2, H2O, He2), The specifically preferred supercritical fluid is void of hydrogen as a means to virtually eliminate hydrogen reduction or hydrogen embrittlement on the heat exchanger coatings or substrate respectively. The particularly preferred supercritical fluid has a disassociation rate less than 0.5% at the operating temperature in which the heat exchanger operates. The specifically preferred heat transfer fluid is the working fluid wherein the combined energy produced (i.e., both thermal, and electrical) displaces the maximum amount of dollar value associated with the displaced energy produced within all of the integrated components including thermodynamic cycle operable within a power generating cycle, vapor compression cycle, heat pump cycle, absorption heat pump cycle, or thermochemical heat pump cycle.

All of the embodiments can be further comprised of a control system operable to regulate the mass flow rate of the working fluid into the solar receiver, with the ability to regulate the mass flow rate independently for each pass by incorporating a fluid tank having variable fluid levels optionally interspersed between at least one pass and the other. One method of control includes a working fluid inventory management system. The control system regulates the mass flow rate through methods known in the art including variable speed pump, variable volume valve, bypass valves, and fluid accumulators. The control system is further comprised of at least one temperature sensor for fluid discharge temperature and at least one temperature sensor for ambient air temperature or condenser discharge temperature.

Exemplary embodiments of the present invention will now be discussed with reference to the attached Figures. Such embodiments are merely exemplary in nature and not to be construed as limiting the scope of the present invention in any manner. The depiction of heat exchangers predominantly as microchannel heat exchangers having linear porting is merely exemplary in nature and can be substituted by complex shaped porting of microchannel dimensions or porting greater than defined by microchannel practice. The depiction of solar collectors predominantly as flat panel non-tracking solar absorbers with integral microchannel heat exchangers is merely exemplary in nature and can be substituted by tracking collectors of 1 axis or 2 axis type, vacuum evacuated tubes or panels, switchable configuration between solar absorber or solar radiator mode, low concentration fixed collector, or high concentration tracking collectors. The depiction of heat pump as a vapor compressor device is merely exemplary and can be substituted with an absorption heat pump. The compressor type can include a positive displacement device, a gerotor, a ramjet, a screw, and a scroll. Furthermore, and importantly, the heat pump can be a turbopump, a positive displacement pump where the selection of the device to increase the working fluid pressure and operate as a mass flow regulator is determined by the density at the inlet pressure and discharge outlet. When the incoming working fluid has a density greater than 50 kg per m3, or preferably greater than 100 kg per m3, or specifically greater greater than 300 kg per m3. The depiction of valves as standard mass flow regulators is merely exemplary in nature and can be substituted by variable flow devices, expansion valve, turboexpander, two way or three way valves. The depiction of methods to remove heat from the working fluid as a condenser is merely exemplary in nature as a thermal sink and can be substituted by any device having a temperature lower than the working fluid temperature including absorption heat pump desorber/generator, process boilers, process superheater, and domestic hot water. The depiction of desiccant dehumidifier as liquid desiccant dehumidifier is merely exemplary and can be substituted by an adsorption solid desiccant dehumidifier, and high surface area hydrophilic powders. The depiction of geothermal as thermal source can be low depth subsurface, moderate depth geothermal wells, or high depth geothermal sources such as obtained from oil wells. The depiction of expander as turbine is merely exemplary as a method to reduce the pressure of the working fluid enables the generation of mechanical or electrical energy and can be substituted by turboexpander, positive displacement device, a gerotor or geroller, a ramjet, screw, or scroll device. The depiction of photovoltaic cell as single concentration device can be substituted by thin film, low concentration device, Fresnel lens, and high concentration devices.

The control system is further comprised of at least one temperature sensor for fluid discharge temperature and at least one temperature sensor for ambient air temperature or condenser discharge temperature.

Exemplary embodiments of the present invention will now be discussed with reference to the attached Figures. Such embodiments are merely exemplary in nature. Furthermore, it is understand as known in the art that sensors to measure thermophysical properties including temperature and pressure are placed throughout the embodiments as known in the art, most notably positioned to measure at least one thermophysical parameter for at least one thermodynamic state point. The depiction of solar collectors predominantly as flat panel non-tracking solar absorbers with integral microchannel heat exchangers is merely exemplary in nature and can be substituted by tracking collectors of 1 axis or 2 axis type, vacuum evacuated tubes or panels, switchable configuration between solar absorber or solar radiator mode, low concentration fixed collector, or high concentration tracking collectors. The depiction of pump as a vapor compressor device is merely exemplary and can be substituted with a positive displacement device, a gerotor, a ramjet, a screw, and a scroll. Furthermore, and importantly, the pump can be a turbopump, a positive displacement pump where the selection of the device to increase the working fluid pressure and operate as a mass flow regulator is determined by the density at the inlet pressure and discharge outlet when the incoming working fluid has a density greater than 10-50 kg per m3, or preferably greater than 100 kg per m3, or specifically greater greater than 300 kg per m3. The depiction of valves as standard mass flow regulators is merely exemplary in nature and can be substituted by variable flow devices, expansion valve, turboexpander, two way or three way valves. The depiction of methods to remove heat from the working fluid as a condenser is merely exemplary in nature as a thermal sink and can be substituted by any device having a temperature lower than the working fluid temperature including absorption heat pump desorber/generator, liquid desiccant dehumidifier, process boilers, process superheater, and domestic hot water. With regard to FIGS. 1 through 17, like reference numerals refer to like parts.

The function of the mass management system is to serve as a means of adding or removing the mass of expandable fluid from the fluid accumulator into at least one circuit of the solar collector. Hereinafter, the term “adding fluid” is increasing the mass of expandable fluid into the fluid accumulator by at least 0.5% on a weight basis. Hereinafter, the term “removing fluid” is decreasing the mass of expandable fluid into the fluid accumulator by 0.5% on a weight basis. It is understood that adding fluid into the fluid accumulator is removing fluid from the at least one circuit of the solar collector, hereinafter referred to as “remove fluid from the solar collector”. And removing fluid from the fluid accumulator is adding fluid into the at least one circuit of the solar collector, hereinafter referred to as “add fluid into the solar collector”.

Turning to FIG. 1, FIG. 1 is a sequential flow diagram of one embodiment of a heat pump with integral solar collector in accordance with the present invention. The circles containing “A” and “B” are state point indicators to provide continuity of working fluid flow between the various alternate scenarios 1 through 4. In the embodiment of FIG. 1 heat pump solar collector is comprised of heat pump 10 in fluid communication with a solar collector 20 with a temperature sensor 32 measuring the discharge temperature of the working fluid from the heat pump 10. Another temperature sensor 30 measures the discharge temperature of the working fluid as it leaves the solar collector 20 and prior to the fluid entering the thermal sink 40 which is in fluid communication with the solar collector 20. Another temperature sensor 31 measures the discharge temperature after leaving the thermal sink 40. A pressure sensor 50 measures the discharge pressure from the heat pump 10, though the actual placement of the pressure sensor 50 can be anywhere downstream of the heat pump 10 discharge and upstream of a pressure-reducing device including an expansion valve or turboexpander. One exemplary method of control is to vary the discharge pressure of the heat pump 10 such that the temperature of the working fluid being discharged after the solar collector, which enables the heat pump energy input to be minimized where the heat pump 10 concurrently achieves the desired working fluid mass flow requirement and discharge temperature prior to the solar collector. The discharge pressure downstream of the heat pump 10 is a function of the solar flux on the solar collector 20 as a method of minimizing the operating costs of the heat pump with integral solar collector as the heat pump requires mechanical and/or electrical energy. The heat of compression resulting from the heat pump provides a high coefficient of performance temperature gain (i.e., lift) that is subsequently increased further by the solar collector 20. The control system decreases the pressure gain to ensure that the thermal sink 40 both achieves the required heat transfer and discharge temperature such that the heat pump, when the solar collector provides the majority of the heat source into the working fluid, operates predominantly as a mass flow regulator resulting in a reduced operating cost of the heat pump. Another advantage of this embodiment is the elimination of a heat exchanger to transfer thermal energy captured from the solar collector 20 into the working fluid, and also eliminating a secondary heat transfer fluid within the solar collector 20. The preferred working fluid is a fluid that has virtually no (e.g., less than 1.0% preferred, less than 0.5% specifically preferred, and less than 0.05% particularly preferred) thermal degradation resulting particularly from solar collector stagnation. One exemplary working fluid includes carbon dioxide, with the particularly preferred embodiment having a heat pump discharge pressure greater than the supercritical pressure of carbon dioxide. Additional working fluids include refrigerants, water, and gases. The particularly preferred embodiment is the selection of carbon dioxide with a discharge pressure greater than it's supercritical pressure and the solar collector 20 being a microchannel device to achieve superior heat transfer with low pressure drops. Another important design advantage is the selection of a heat pump 10 device that either operates oil free, thus eliminating the potential of hydraulic oil from disassociating (i.e., breaking down) with the solar collector 20. Alternatively the heat pump can utilize an electrostatic collector to collect any lubricant utilized within the heat pump, with one exemplary being ionic liquids. The ionic liquid has the further advantage of having essentially no vapor pressure in combination of having electrostatic attraction as a method of limiting the heat pump 10 lubricant from entering the solar collector 20. FIG. 1 shows four alternative configurations such that “A” is the inlet of the working fluid into the heat pump 10, and “B” is the discharge of the working fluid downstream of the thermal sink 40. The first alternate “alternate 1” depicts an expander 60 downstream of the thermal sink 40 as a method of recovering at least a portion of the mechanical/electrical energy expended during in order to obtain the heat pump compression. This alternate configuration would be typical for domestic hot water, air conditioning, refrigeration, industrial processes including processes currently serviced by traditional combustion powered boilers, furnaces, dryers, etc. The expander's 60 discharge pressure is regulated by using feedback on the measured pressure by pressure sensor 50 and discharge temperature as measured by temperature sensor 33. It is further anticipated that an external combustor can be downstream of the solar collector 20 and upstream of the thermal sink 40 as a method to further increase the working fluid temperature. This configuration is especially desired for industrial or power generation processes that involve heating of air (i.e., less dense than working fluid thus requiring significantly larger heat exchangers) as a method of superheating the working fluid to the desired operating temperature of the thermal sink 40. The invention utilizing the same working fluid for the heat pump as the solar collector for temperatures exceeding 350C can only be done using a small set of working fluids most notably ammonia and particularly preferred carbon dioxide “CO2”. Water is another alternative fluid, though less desirable due to the discontinuous thermophysical properties as the water transitions to steam. The second alternate configuration replaces the expander with an expansion valve 90 where the expansion valve as known in the art can operate as a variable controlled device, open/close switch, and modulated to be a pulsing device to enhance heat transfer properties. The expansion valve, which is a special type of fluid control valve 90 enabling pressure reduction discharge pressure is regulated by using feedback on the measured pressure by pressure sensor 52 and discharge temperature as measured by temperature sensor 34. This configuration, though not as efficient as alternate 1, has a lower capital cost thus being implemented when the system scale or financial return on investment doesn't justify the additional expense of an energy recovery expander 60. The working fluid downstream of the expansion valve provides cooling through an evaporator 80 thus operating as an air conditioner, chiller, refrigerator, or freezer which is dependent on the discharge temperature as measured by temperature sensor 34. Alternate configuration 3 simply depicts a closed loop system such that the heat pump effectively operates as a mass flow regulator, whereby the pressure gain between the heat pump 10 inlet is a nominal amount solely to overcome pressure losses associated with the working fluid passing through the entire circulation loop including the solar collector 20. Alternate configuration 4 is further comprised of a fluid accumulator 130 and a control valve 95 as a method to buffer the inventory of working fluid within the circulation loop. The fluid accumulator in its simplest form operates as a temporary storage of working fluid when the operating pressure within the circulation loop is within 10 psi of the maximum operating pressure of any individual component. The invention incorporates a control system to open and close valving of the alternate 4 configuration, which is preferably configured as a parallel circuit with any of the prior alternate configurations. The preferred embodiment has an operating pressure at state point A of less than the supercritical pressure of the working fluid, which for CO2 is less than 1000 psi. The particularly preferred embodiment has a working fluid pressure of less than 800 psi. Another embodiment is the heat pump cycle operating as a fully subcritical cycle in which state point A has an operating pressure of less than 400 psi. The operating pressure at state point B is preferred to be supercritical, which for CO2 is above 1200 psi as to ensure low pressure drop throughout the solar collector 20. The pressure differential across the heat pump 10 is varied such that the working fluid has a compressibility greater than 10%, which is dependent on realizing a heat of compression greater than 10 degrees Fahrenheit. The particularly preferred heat of compression is the greater of 20 degrees Fahrenheit, or such that the temperature downstream of heat pump 10 is at least 15 degrees Fahrenheit higher than the ambient air temperature. The preferred method of control is to operate the low-side pressure of the heat pump when under Alternate 2 such that the expansion yields a cooling temperature of at least 2 degrees Fahrenheit cooler than the air conditioning or refrigeration set point. Under Alternate 2 it is further desirable to maximize the combined thermal heating by first stage of heat of compression followed by the solar collector, whereby the solar collector heating varies in real-time as a function of the thermal sink mass flow rate (i.e., heating domestic hot water, industrial process heating, etc.) and solar irradiance flux. The low-side circuit pressure (i.e., upstream of heat pump 10) and pressure ratio under Alternate 1 is selected such that the mechanical work realized by the expander 60 closely matches the work input requirement of the heat pump 10 to minimize electricity requirements.

Turning to FIG. 2, FIG. 2 is a sequential flow diagram of one embodiment of a heat pump with integral solar collector in accordance with the present invention. In the embodiment of FIG. 2 heat pump solar collector the heat pump 10 upstream of the solar collector 20 is further comprised of a fluid accumulator 130 configured predominantly as an emergency working fluid inventory storage vehicle where an open/close fluid valve 90 enables a partial stream of the working fluid, which is now at the higher pressure as measured by pressure sensor 50 having a temperature as measured by temperature sensor 31. The working fluid passes through a condenser 70 in order to increase the density of the working fluid prior to entering the fluid accumulator 130. The preferred configuration of the condenser 70 is within the fluid accumulator 130, thus enabling the condenser (effectively a heat exchanger) to operate as an evaporator/heater. The control system would switch the condenser from cooling to heating mode once the heat pump discharge pressure (i.e. working fluid pressure downstream of the heat pump discharge) becomes at lower than the maximum operating pressure minus an anti-cycling threshold. The control system would then subsequently open the valve 90 once the working fluid within the fluid accumulator 130 exceeds the target set point as measured by temperature sensor 30.

Turning to FIG. 3, FIG. 3 is a sequential flow diagram of one embodiment of a heat pump with integral solar collector in accordance with the present invention. In the embodiment of FIG. 3 heat pump solar collector depicts one scenario having parallel circuits and multiple thermal sinks. The heat pump 10, as noted earlier can operate as mass flow regulator (i.e., booster pump), more traditional vapor compressor, or more traditional turbopump. A control system operates the valves as a method of controlling the mass flow within each parallel circuit. The top circuit is controlled by valve 90 to enable the working fluid to pass through the solar collector 20. The invention anticipates the solar collector 20 operating either as a solar absorber or solar radiator thus providing the ability to provide “free” heating or cooling respectively by leveraging the high surface area. The working fluid downstream of the solar collector 20 transfers thermal energy via a heat exchanger 80, which can be manufactured using a wide range of materials (e.g., conductive polymers, aluminum, stainless steel, etc.) and designed using methods known in the art (e.g., microchannel, shell and tube, plate, etc.), into a thermal sink #2 41. The working fluid downstream of the heat exchanger 80 mixes with working fluid that passes through valve 91, thus effectively operating as a solar collector bypass valve, and sequentially passes through a second thermal sink 40 that has a lower target set point than thermal sink 41. Another thermal sink #3 42 as depicted removes more thermal energy from the working fluid, though the working fluid temperature will be at a lower temperature than the two aforementioned thermal sinks 41 and 40. The last depicted valve 92 enables working fluid to enter the fluid accumulator 130. The full working features as noted in FIG. 2 are not repeated visually for the purpose of brevity. A key feature of the heat pump system is the ability to adapt to changing solar conditions, ambient weather conditions (e.g., such as changing temperatures and humidity levels), and changing thermal load requirements (e.g., both heating and cooling). Fluid valves 90, 91, and 92 are optimally variable flow valves enabling the full mass flow rate achieved by the heat pump 10 to be segmented to meet the individual heat transfer requirements of thermal sink 40, 41, and 42. As each fluid valve is modulated the working fluid inventory within the thermodynamic cycle varies, and thus the inventory management within the fluid accumulator 130 must modulate fluid valves 92 and 93 to enable fluid to be added and removed from the thermodynamic cycle high-side and low-side circuits.

Turning to FIG. 4, FIG. 4 is a sequential flow diagram of one embodiment of a heat pump with integral solar collector in accordance with the present invention. In the embodiment of FIG. 4 heat pump solar collector operates as a radiant cooler. A heat pump 10 increases the operating pressure as measured by the pressure sensor 50 of the working fluid which also has its temperature increased due to heat of compression as measured by temperature sensor 30. A secondary heat transfer fluid, such as domestic hot water is circulated by a pump 160 through a heat exchanger 80 to remove thermal energy of the working fluid through a thermal sink 40. This serves the purpose of providing the first stage of cooling prior to reaching the solar collector 20 configured in the radiant cooling (i.e., thermal emitting as opposed to solar absorbing) mode. The inlet temperature into the solar collector 20 is measured by temperature sensor 31 and the discharge temperature is measured by temperature sensor 32. The solar collector 20 when operating as a radiant cooler dissipates black body radiation to the sky and therefore effectively operates as a precooler/subcooler to the working fluid prior to reaching the expansion valve 91. The now expanded working fluid provides cooling that absorbs thermal energy from a thermal source in thermal communication with the evaporator 80. The heat pump 10 inlet pressure and temperature are measured respectively by pressure sensor 51 and temperature sensor 33. An alternate configuration for the thermal sink 40 is depicted in alternate 1 as an air condenser utilizing condenser fans 100 instead of a secondary heat transfer fluid.

Turning to FIG. 5, FIG. 5 is a sequential flow diagram of one embodiment of a heat pump with integral solar collector in accordance with the present invention. In the embodiment of FIG. 5 heat pump solar collector depicts another configuration for switching the solar collector 20 between a thermal sink 40 and thermal source mode. In this configuration the solar collector, which is optionally under vacuum while operating in thermal source mode, the solar collector has ambient air flowing over the solar collector 20 surface area. The working fluid then subsequently passes through the thermal sink 40. Two two-way valves 111 and 110 are depicted here to switch fluid flow direction such that the heat pump can operate in air conditioning or heating mode, known in the art as a reversible heat pump. The heat pump 10 has the common evaporator 80 and expansion valve 91 (alternatively expander) and condenser (which is depicted as either the thermal sink 40 or solar collector 20). Configuration 1 depicts the solar collector 20 operating as a radiant cooler. Under such a radiant cooler mode, the heat pump 10 consumes electricity as provided by either the electrical grid or off-grid renewable energy. The heat pump operating parameters such as high-side pressure and low-side pressure are varied to meet the specific requirements of thermal sink #1 40 and cooling levels required as realized by evaporator 80. Again, alternate 1 enables the use of condenser fans 100 to accelerate the removal of heat from the working fluid, where the thermal sink #1 40 is operable as an air side condenser.

Turning to FIG. 6, FIG. 6 is a sequential flow diagram of one embodiment of a heat pump with integral solar collector in accordance with the present invention. In the embodiment of FIG. 6 heat pump 10 solar collector 20 is depicted further comprising a liquid desiccant generator 120 and geothermal 140 as a thermal sink. It is understood that the heat pump with integral solar collector can operate with either the liquid desiccant generator 120 or the geothermal 140 heat sink, as well as the shown combination. The heat pump 10 increases the operating pressure of the working fluid in part by utilizing a controllable two way valve 111 to provide back pressure upstream of the solar collector 20, while also serving as a mass flow control (i.e., working fluid pump). The solar collector 20 increases the working fluid temperature of the portion of the working fluid being transported through the collector as determined by the control system and regulated by the amount of fluid bypass again with the two way valve position 111. The operation in FIG. 6 depicts the heat pump 10 operating as an air conditioning or refrigeration device to provide the sensible cooling while the liquid desiccant generator 120 provides the latent cooling. The goal is thus to provide cooling therefore a significant portion of the working fluid is desired to bypass, whereby regulating fluid diode 700 prevents backflow into the heat exchanger 80. The solar collector 20 boosts the working fluid temperature through a heat exchanger 80 as required to regenerate the liquid desiccant solution. The working fluid having been transported through the parallel circuit is combined upstream of the condenser 70 where the working fluid temperature approaches the ambient temperature. It is understood that the condenser 70 can be selected from the range of known condensers including wet, air, evaporative, etc. FIG. 6 also depicts a working fluid mass management control system though represented for brevity by a control fluid valve 93 to enable working fluid to enter or leave the fluid accumulator 130 as noted in the earlier embodiments. The working fluid can then be optionally subcooled through a heat exchanger 80 in thermal communication with a shallow depth (i.e. surface as known in the geothermal heat pump application, as compared to deep well geothermal for power generation) geothermal 140 that serves as a thermal sink upstream of the expansion valve 92. The fluid control valve 92 operates as an expansion valve to decrease the operating pressure while enabling rapid cooling of the working fluid that subsequently absorbs heat through the evaporator 80.

Turning to FIG. 7, FIG. 7 is a sequential flow diagram of one embodiment of a heat pump with integral solar collector in accordance with the present invention. In the embodiment of FIG. 7 heat pump solar collector depicts an integral power generating cycle with an air conditioning/refrigeration thermodynamic cycle where both systems operate on the same working fluid. Beginning the cycle downstream of the heat pump 10, the heat pump 10 increases the working fluid pressure to the same low side pressure of the power generating cycle (which is downstream of the valve 91, fluid diode 700 to prevent backflow and condenser 70). The working fluid downstream of the heat pump 10 then passes through the condenser 71 to condense the working fluid prior to reaching the pump 160 as a method of limiting cavitation. The pump 160 subsequently raises the working fluid, which is now at a significantly higher density, to the power generating high side pressure. The high pressure working fluid, which has increased the working fluid temperature by the heat of compression, now passes through the solar collector 20 to vaporize and optionally to superheat the fluid as a means of increasing the enthalpy and thermodynamic efficiency of the power generating cycle. The now superheated working fluid enters the expander (e.g., turbine) 150 inlet in order to produce shaft work (i.e., mechanical energy) that can further be transformed into electricity or hydraulic energy. As known in the art, the working fluid enters the condenser 70 in order to reduce the pumping energy requirements to return the relatively cool working fluid to the high side pressure. It is understood that the turbine can be any expander device, as the pump can also include a turbopump or positive displacement devices. The control system regulates in real time the mass flow of the working fluid that will further be expanded in order to match the air conditioning/refrigeration demands with thermal energy being transferred through the evaporator 80. It is further understood that the pump 160, heat pump 10, and expander 150 can operate at partial loads through means as known in the art. The heat pump 10 can optionally have an electric motor 1000 with a decoupling mechanism such as a decoupler 1010 to engage or disengage the electric motor. Though depicted only in FIG. 7, it is understood that the electric motor/generator 1000 and decoupler 1010 can be implemented in all scenarios for heat pump operation.

Turning to FIG. 8, FIG. 8 is a sequential flow diagram of one embodiment of a heat pump with integral solar collector in accordance with the present invention. In the embodiment of FIG. 8 heat pump solar collector depicts a hybrid solar thermal and photovoltaic configuration. The precise objective of the integrated heat pump and photovoltaic cell system is to operate with the control system pressure and temperature control such that the working fluid transforms from a liquid/supercritical to a vapor/superheated fluid within the backside of the photovoltaic cell 200. The operating pressure is dynamically modulated such that the temperature at state point #2 is less than lesser of the maximum junction temperature of PV cell 200 or desired operating temperature. The working fluid subsequently passes through a solar collector 20 to ensure that the working fluid doesn't create cavitation in the heat pump 10. The now high pressure working fluid also at the elevated temperature due to heat of compression is at sufficiently high temperatures to drive a range of thermal sinks. These thermal sinks include thermally activated chillers, such as single, double or triple effect absorption chillers, and adsorption chillers 230. Subsequently the working fluid passes through thermal sinks requiring sequentially lower operating temperatures such as process heat 240 and then domestic hot water 250. The control system will enable the working fluid to pass through the condenser 70 in the event the working fluid temperature remains higher than the ambient or wet bulb temperature, which would be obtained by activating the condenser fans/motors. The working fluid now transfers thermal energy by absorbing energy through the evaporator 80 and now returning to the backside of the PV cell 200 where thermal energy is transferred into the working fluid through the embedded microchannel heat exchanger 210.

Turning to FIG. 9, FIG. 9 is a sequential flow diagram of one embodiment of a heat pump with integral solar collector and/or combustor in accordance with the present invention. In the embodiment of FIG. 9 heat pump solar collector depicts a hot water or steam heat pump utilizing the same working fluid within the entire system.

The specific implementation is a more efficient alternative to traditional boilers, as the coefficient of performance “COP” is greater than 1.0. The particularly preferred COP is greater than 1.20, and the specifically preferred COP is greater than 1.60. The method of control includes a dynamic control system that ensures the operating temperature of the working fluid downstream of the solar collector 20, which is preferably a microchannel heat exchanger, is less than the maximum working fluid temperature and also to ensure that the working fluid is a vapor prior to entering the heat pump 10. The optimal control system has the means to control the discharge pressure, the mass flow rate, and bypass valves including a variable fluid valve 91 to preferably a variable position that modulates the transferring of heat from the working fluid into the hot water/steam system supply B. Flow points A and B are utilized to respectively indicate water/steam flow more clearly where A is relatively cold temperatures as compared to B. Beginning at the cold water source, two circulating pumps 161 and 162 regulate the mass flow rate into the two respective thermodynamic cycles with second thermodynamic cycle (i.e., power generation) and first thermodynamic cycle (i.e., heat pump). Optimally, the thermodynamic cycle has a high-side and a low-side pressure with a high-side pressure having an operating pressure of at least 50 psi greater than a low-side pressure. The one mass flow regulator (i.e., heat pump 10) is operable for both increase the working fluid pressure from the low-side pressure to the high-side pressure and for removing or adding working fluid from the thermodynamic cycle into the fluid accumulator. The cold water discharged by circulating pump 161 enters the heat exchanger 802, which is downstream of the expander 150, thus concurrently operates as a condenser in the power generation cycle. The power generation cycle can operate as either a Brayton or Rankine cycle. At ambient temperatures lower than 65 degrees Fahrenheit, the optimal cycle is a Rankine cycle with a pressure ratio across the expander 150 of greater than 2.2, and preferably greater than 2.7. Under ambient conditions greater than 90 degrees Fahrenheit, a Brayton cycle is preferred. Continuing the working fluid enters into heat exchanger 803, which is essentially a hybrid regenerator between the second and first thermodynamic cycles. Heat is transferred from the second thermodynamic cycle for the purpose of reducing the compressibility of the working fluid, and thus minimizing compression energy (i.e., maximize power generation); while concurrently preheating the working fluid prior to the heat pump 10, serving as both preheat and eliminating the potential for cavitation or liquid-lock. The now relatively warmer working fluid, which is compressible, is increased to the high-side circuit pressure of the second thermodynamic cycle by the circulating pump 160 (i.e., turbopump, turbocompressor, etc.) whereby the working fluid is heated externally by either or both solar collector 20 and supplemental combustor 300 of fuel. The now superheated working fluid enters the expander 150 to produce mechanical shaft power, which is used to provide required energy to the heat pump 10. The discharge from the expander remains hot, on the order of100 degrees Celsius below the discharge temperature from heat exchanger 801, which this now excess heat is transferred to heat the cold water/steam. The other path for creating hot water/steam is circulated by circulating pump 162 into the heat exchanger 805, which obtains its thermal energy from the heat pump 10 heat of compression followed by waste heat recovery of combustor exhaust 301. The working fluid exiting heat exchanger 805 is flow regulated by fluid valve 91 operable as an expansion valve.

Turning to FIG. 10, which is the reconfiguration of FIG. 9 for producing chilled water or air conditoning instead of hot water/steam, the thermal sources of solar collector 20 and combustor 300 are transferred into the working fluid of the second thermodynamic cycle to maximize power production to drive the expander 150 via heat exchanger 801. The fundamental difference is that the combustor exhaust 301 is now used to preheat the working fluid entering the heat pump 10 to maximize the thermal lift via heat exchanger 802, with the available thermal energy being dissipated from the working fluid of the first thermodynamic cycle through condenser 70 (which can effectively be any heat exchanger providing heat to a wide range of devices such as absorption chillers, or industrial process heat). The now “cooled” working fluid is prepared to go through an expansion valve to provide cooling.

Turning to FIG. 11, which is another reconfiguration of FIG. 9, for utilizing harvested solar thermal energy via the solar collector 20. The preheated working fluid is further heated by combusting fuel in the combustor 300. The now superheated working fluid enters the expander 150 to maximize power production.

Turning to FIG. 12, which is yet another reconfiguration of FIG. 9, depicts the combustor exhaust gas 301 serving as a second stage of heating following the heat pump 10 heat of compression. The heat exchanger 801 recovers the waste heat from exhaust gas, which particularly under oxyfuel combustion has reduced volume for enhanced heat transfer with a smaller heat exchanger, and the configuration of the heat exchanger 801 as known in the art to withstand corrosives resulting from condensable gas byproducts (NOx, SOx, etc.). The working fluid is finally superheated by the solar collector 20 prior to being discharged.

Turning to FIG. 13, which is yet another reconfiguration of FIG. 9, but for produced chilled water, air conditioning or refrigeration. The fundamental advantage of this configuration as compared to provisional filing and prior art is the absence of a regenerator, thus all heat transfer out of the second thermodynamic cycle is at the low-side circuit pressure. Beginning the second thermodynamic cycle at the discharge of the circulating pump 160 (i.e., turbopump, turbocompressor, etc.), the working fluid then is heated either directly by flowing through microchannel solar collectors (i.e., having integral microchannel heat exchanger 801) or indirectly from combustor 300 through the heat exchanger 801. The now superheated working fluid enters the expander 150 to produce mechanical energy to drive directly the heat pump 10. The now low-pressure working fluid has thermal energy transfer via heat exchanger 804 to any of a wide range of thermally activated chillers 230 (e.g., double effect, single effect absorption, adsorption, etc.). Subsequent thermal energy is transferred to a desiccant generator 900 via a heat exchanger 802, whereby the desiccant generator handles the latent load. Any remaining waste heat from the second thermodynamic power generating cycle is removed by the condenser 70 in order to minimize circulating pump 160 energy requirements. The first thermodynamic cycle is optimized for cooling by removing heat of compression through heat exchanger 805 (i.e., operable as a condenser), then pre-cooling through heat exchanger 806 using ground source geothermal 910, and then using evaporative cooling 920 via heat exchanger 807. The now pre-cooled and sub-cooled working fluid is expander through fluid valve 91 to provide cooling through heat exchanger 803 (i.e., operable as an evaporator). Alternate 1 simply changes the order of the ground source geothermal 910 and the evaporative cooler 920. It is understood that this configuration does not require both geothermal and evaporative precooling.

Turning to FIG. 14, a reconfiguration of FIG. 13, integrates additional flexibility and adaptability to changing conditions. Beginning with the heat pump 10 heat of compression and preventing any backflow via fluid diode 700, the working fluid is directed through the two way valve 110 downstream of the heat pump 10. The two way valve 110, under conditions suitable for radiant cooling directs working fluid into solar collector 20 with another downstream fluid diode 700 again to prevent backflow. Alternatively under conditions suitable for solar energy harvesting the working fluid is diverted to the solar collector 20. When sufficient thermal energy is available from the solar flux the working fluid is directed to the expander 150 to produce power and again using a fluid diode 700 to prevent backflow. When conditions do not meet radiant cooling or solar harvesting, the heat pump 10 operates as a traditional CO2 based heat pump providing heat of compression. The now relatively warm working fluid can be utilized for a series of thermal loads including thermal activated chiller 230, desiccant generator 900 and domestic hot water 250, all via respectively heat exchangers 805, 804, and 803. Any remaining waste heat is removed via the condenser 70. In the event that cooling is required, the working fluid is directed to heat exchanger 802 in which evaporative cooling 920 removes additional thermal energy and now returns back to the heat pump 10 inlet as surrounded by a series of fluid diodes 700 preventing backflow. The working fluid mass management system is depicted, where the fluid accumulator 130 obtains working fluid from the high-side circuit pressure and is removed from the accumulator into the low-pressure circuit side upstream of the heat pump 10. Alternate 1 simply depicts the heat pump and expander on the same shaft, such to enable both the heat pump 10 and expander 150 to be in one hermetically sealed chamber, thus having an important secondary benefit of increasing the operating pressure of any working fluid leaking from the power generating expander 150. The two overlapping thermodynamic cycles (i.e., power generating thermodynamic loop and a heat pump thermodynamic loop) has the working fluid leaking from the power generating expander increased to a pressure of at least 5 psi greater than the low-side pressure of the power generating thermodynamic loop.

Turning to FIG. 15, Removing Fluid from Accumulator (Adding Fluid into Solar Collector): There are two methods to remove working fluid from the fluid accumulator 130 with the first being the use of the solar collector 20 to heat a portion of the working fluid remaining in the main closed loop system by absorbing solar flux and transferring this thermal energy via an embedded heat exchanger within the solar collector 20, and the second being the use of the condenser 70 as a heat source (as compared to the traditional role as a heat sink). Utilizing the first method, the heat pump 10 prevents backflow during normal operation, and the control system activates the hot inlet valve 93 to the open position when the solar collector 20 has heated the working fluid to a target set point temperature (i.e., achieved a specified density by way of the operating pressure and working fluid temperature). The discharge fluid valve 93 is subsequently opened by the control system to enable the relatively low density and higher temperature working fluid to displace the relatively more dense and lower temperature working fluid. The method of control includes the ability to monitor heat pump 10 energy consumption by methods known in the art including mass flow meter, kilowatt-hour meter, pump performance maps with a known inlet and discharge pressure, working fluid inlet temperature, and working fluid discharge temperature. The control system can also utilize a database of NIST thermophysical properties to precisely calculate the amount of working fluid within the fluid accumulator 130, or within the closed loop system.

Adding Fluid: The best method of adding fluid, (i.e., discharging fluid from the fluid accumulator into the at least one circuit of the solar collector) centers around the condenser 70 in thermal communication with heat exchanger 802 operating in reverse mode as the removing fluid mode, thus as a thermal source instead of a thermal sink. Under this method, the control system will begin the process of using a relatively higher temperature and lower density heat transfer fluid into the embedded heat exchanger of the fluid accumulator 130 at which point of reaching either or both the target set point temperature and/or target set point pressure the cold fluid valve 90 is opened (this assumes that the resulting pressure within the fluid accumulator is at least temporarily higher than the closed loop system pressure).

Turning to FIG. 16, FIG. 16 is a sequential flow diagram of one embodiment of a solar collector with integral mass management system in accordance with the present invention. In the embodiment of FIG. 16 the fluid accumulator discharges directly into the solar collector preferably operating as a thermosiphon. Beginning with the working fluid at state point A, at least a portion of the working fluid passes through the hot inlet valve 93 when the fluid accumulator is removing working fluid from the main closed loop of the solar collector thermosiphon system. As with any thermosiphon system it is critical that the fluid accumulator 130 be located above the solar collector. The expandable working fluid having entered the fluid accumulator 130 is cooled through the heat exchanger 802, which is preferably contained within the fluid accumulator. The heat transfer fluid utilized to cool the working fluid is through the accumulator condenser 70. The then subsequently cooled working fluid within the fluid accumulator 130 is discharged through the discharge valve 93 back into the solar collector 20, when desired and controlled by a control system to regulate the combination of mass flow rate of the working fluid and the operating pressure of the working fluid within the safe margins of operation. It is understood that temperature sensors can be placed at each state point, including within the fluid accumulator to enable the control system to regulate the flow of working fluid, and heat transfer fluid to remove thermal energy from the working fluid as a means of heating up a thermal sink including domestic hot water, industrial processes, heating, and even power generation. The depiction within FIG. 16, notably the right half of the drawing shows the utilization of a heat transfer fluid that ultimately is heated by the solar collector 20 (on the bottom right side, which is effectively the same as solar collector 20 (graphically and physically above it) but showing the relative height of each component to each other) whereby the working fluid removed from the main closed loop transfers a portion of its thermal energy to increase the density of the stored fluid and is conserved by subsequent transfer of the thermal energy to increase from state point T1 33.1 as it passes through valve 90 and the fluid accumulator condenser 70 via heat exchanger 803, now becoming state point D having a temperature sensor T2 33.2. This stage effectively operates as a preheat of the heat transfer fluid, then passes through the condenser 70 of the main loop now becoming state point E having a temperature sensor T3 33.3 to continue the flow through the solar collector 20. The operation of the solar collector as a thermosiphon requires T1<T2<T3.

It is anticipated that the removal of working fluid from the closed loop system into the fluid accumulator 130 can result from the solar collector operating in essentially a stagnation mode (thus being a safety precaution to limit the solar collector from exceeding it's maximum operating pressure specifications), the closing and/or evacuation of a parallel circuit within the closed loop system, capturing at least a portion of the working fluid “charge” within the closed loop system prior to maintenance of the entire system, enabling the solar collector to operate at relatively higher ambient temperatures, and/or enabling the solar collector to operate at relatively lower operating pressure. The counterpart is the addition of working fluid into the closed loop system from the fluid accumulator 130 as a result of relatively lower ambient temperatures, the opening and/or filling of a parallel circuit within the closed loop system, enabling the solar collector to operate at relatively lower ambient temperatures, and/or enabling the solar collector to operate at relatively higher operating pressure.

Turning to FIG. 17, the inventory management system with the central element of fluid accumulator 130 is in thermal communication with the condenser 70 via the heat exchanger 802. Fluid is discharged from the fluid accumulator 130 via the discharge fluid valve 93 into the low-pressure circuit side of the heat pump 10. Fluid enters the fluid accumulator 130 either directly through the cold fluid valve 90 or the hot fluid valve 93 respectively when inventory is desired to be increased and inventory is desired to be decreased in the fluid accumulator 130. In all cases fluid entering the fluid accumulator 130 is from the high-pressure circuit side of the heat pump 10. When desiring relatively hot working fluid, the working fluid is heated either by the solar collector 20 or the combustor 300. The heat pump system must adapt quickly when high-side pressure circuits 901 are opened or closed, as well as low-side pressure circuits 902.

It is understood in this invention that a combination of scenarios can be assembled through the use of fluid valves and/or switches such that any of the alternate configurations can be in parallel enabling the solar collector to support a wide range of thermal sinks.

The power generating expander 150 is designed to provide all of the generated power in the form of mechanical shaft power and further designed for the mechanical shaft power to power the mass flow regulator. The use of the fluid valves 90 serve as a back pressure regulator for the heat pump thermodynamic loop enabling to vary the high-side pressure of the heat pump thermodynamic loop to consume all of the mechanical shaft power generated by the power generating expander.

FIG. 7 depicts the use of an electric motor to generate mechanical shaft power to operate the one mass flow regulator (i.e., heat pump 10) when insufficient power is available from the power generating expander 150. The electric motor has a method of decoupling (i.e., magnetic, physical, or electrical decoupler) designed to either electrically or magnetically decouple the electric motor or mechanically disconnect the electric motor from both the heat pump 10 and the power generating expander 150.

The fluid accumulator when operating in the thermosiphon configuration is designed to be void of a second mass flow regulator consuming greater than 20 watts of mechanical or electrical power. This is particularly realized when the working fluid is at a pressure where a decrease in density per 10 degrees Fahrenheit increase is at least one percent. The configuration of the fluid accumulator 130 is such that at least one fluid inlet port is at least one inch higher than the at least one fluid discharge port. The method of adding working fluid is designed to have volumetric displacement of working fluid in the fluid accumulator with working fluid from the high-pressure circuit side having a density of at least one percent lower than the working fluid within the fluid accumulator 130. Another method of adding working fluid with an increased rate of fluid addition by at least 5 percent is by preheating the temperature of the high-pressure circuit side at least 10 degrees Fahrenheit greater than the working fluid temperature within the fluid accumulator. Yet another method of adding working fluid is by using solar collectors 20 downstream of the heat pump 10 to increase the working fluid temperature by at least 5 degrees Fahrenheit, or to increase the rate of fluid addition by at least 5 percent through cooling the working fluid temperature within the fluid accumulator by at least 5 degrees Fahrenheit. While removing working fluid is best done by decreasing the working fluid temperature by at least 5 degrees Fahrenheit, or by using volumetric displacement of the working fluid in the fluid accumulator with working fluid from the high-pressure circuit side having a density of at least one percent greater than the working fluid within the fluid accumulator.

Optimal conditions of the overlapping thermodynamic cycle has the high-side pressure circuit of the second thermodynamic cycle at least 5 psi greater than the low-side pressure circuit of the first thermodynamic cycle.

Another optimal condition is achieved when the power generating system has solid state conversion devices including photovoltaic, thermophotovoltaic, thermoelectric, or thermionic cell. The high-side pressure is modified to not exceed a maximum junction temperature using a backpressure regulator. The operating pressure is selected to maintain a phase change working fluid temperature within 5 degrees Fahrenheit of the lesser of solid state conversion device maximum junction temperature or design temperature.

The combined power generating and heat pump consuming efficiency is realized when the second thermodynamic cycle is void of any heat exchangers having thermal communication between a high-pressure circuit side of second thermodynamic cycle and low-pressure circuit side of second thermodynamic cycle.

The particularly preferred working fluid is carbon dioxide, with the high-side circuit pressure of the second thermodynamic cycle greater than 2000 psi, and the high-side circuit pressure of the first thermodynamic cycle is greater than 800 psi. Another embodiment is with the high-side circuit pressure of the second thermodynamic cycle greater than 2700 psi, the high-side circuit pressure of the first thermodynamic cycle is greater than 1200 psi, the high-side circuit pressure of the second thermodynamic cycle is greater than 2.2 times the low-side circuit pressure of the second thermodynamic cycle, and the high-side circuit pressure of the first thermodynamic cycle at least 5 psi greater than the low-side circuit pressure of the second thermodynamic cycle.

Yet another embodiment is where a heat exchanger is used to transfer thermal energy from the second thermodynamic cycle low-pressure circuit side to the regenerator of the dehumidification (i.e., desiccant generator) to provide latent cooling, and a heat exchanger from the first thermodynamic cycle high-pressure circuit side operable as a condenser and wherein the first thermodynamic cycle is operable in a cooling mode and the second thermodynamic cycle is operable as a mechanically interconnected power source to the at least one mass flow regulator.

Although the invention has been described in detail with particular reference to certain embodiments detailed herein, other embodiments can achieve the same results. Variations and modifications of the present invention will be obvious to those skilled in the art and the present invention is intended to cover in the appended claims all such modifications and equivalents.

Claims

1. A heat pump system comprising one working fluid in at least one thermodynamic cycle and one mass flow regulator circulating a working fluid selected from at least one heat transfer fluid of water, carbon dioxide, and ammonia; both a high-side pressure circuit downstream of the one mass flow regulator and a low-side pressure circuit upstream of the one mass flow regulator; and wherein the one mass flow regulator consumes mechanical or electrical power of greater than 20 watts.

2. The heat pump system of claim 1 further comprised of a microchannel solar collector having a microchannel diameter of less than 2.5 millimeters.

3. The heat pump system of claim 1 wherein the at least one mass flow regulator increases microchannel solar collector working fluid.

4. The heat pump system of claim 1 further comprised of at least two heat exchangers, wherein the at least one mass flow regulator is operable in a) power generation, b) heating, or c) cooling mode.

5. The heat pump system of claim 2 wherein the microchannel solar collector has at least two individually controlled circuits.

6. The heat pump system of claim 2 further comprised of a fluid accumulator tank and wherein the fluid accumulator tank is between the at least two individually controlled circuits.

7. The heat pump system of claim 2 wherein the microchannel solar collector is operable in either solar absorbing or thermal emitting mode.

8. The heat pump system of claim 1 further comprised of a power generating expander, a fluid accumulator, a thermodynamic cycle having a high-side and a low-side pressure with a high-side pressure having an operating pressure of at least 50 psi greater than a low-side pressure, wherein the one mass flow regulator is operable for both increasing the working fluid pressure from the low-side pressure to the high-side pressure and for removing or adding working fluid from the thermodynamic cycle into the fluid accumulator.

9. The heat pump system of claim 1 further comprised of at least one heat exchanger for independent control of sensible cooling and at least one heat exchanger for independent control of latent cooling.

10. The heat pump system of claim 9 wherein the at least one heat exchanger for independent control of sensible cooling and at least one heat exchanger for independent control of latent cooling designed to remove thermal energy from the thermodynamic cycle and to displace any heat exchangers between the low-side pressure and high-side pressure.

11. The heat pump system of claim 8 wherein the power generating expander and the one mass flow regulator are both contained within a hermetically sealed chamber.

12. The heat pump system of claim 11 wherein the one mass flow regulator is designed to increase the operating pressure of any working fluid leaking from the power generating expander.

13. The heat pump system of claim 12 having two overlapping thermodynamic cycles comprised of a power generating thermodynamic loop and a heat pump thermodynamic loop, wherein the any working fluid leaking from the power generating expander is increased to a pressure at least 5 psi greater than the low-side pressure of the power generating thermodynamic loop.

14. The heat pump system of claim 11 wherein the power generating expander is designed to provides all of the generated power in the form of mechanical shaft power and further designed for the mechanical shaft power to power the mass flow regulator.

15. The heat pump system of claim 14 further comprised of a back pressure regulator for the heat pump thermodynamic loop wherein the back pressure regulator is designed to vary the high-side pressure of the heat pump thermodynamic loop to consume all of the mechanical shaft power generated by the power generating expander.

16. The heat pump system of claim 11 further comprised of an electric motor wherein the electric motor is designed to generate mechanical shaft power to operate the one mass flow regulator.

17. The heat pump system of claim 16 further comprised of an electric motor decoupler designed to either electrically or magnetically decouple the electric motor or mechanically disconnect the electric motor from both the one mass flow regulator and the power generating expander.

18. The heat pump system of claim 16 further comprised of an electric motor coupled designed to either electrically or magnetically engage the electric motor or mechanically connected the electric motor to the one mass flow regulator.

19. The heat pump system of claim 1 further comprised of a fluid accumulator tank in fluid communication with both high-side pressure circuit and low-side pressure circuit, wherein the one mass flow regulator is designed to switch between a mode to remove working fluid from the high-side pressure circuit into the fluid accumulator and a mode to add working fluid from the fluid accumulator into the low-side pressure circuit, and wherein the fluid communication with the fluid accumulator is designed to be void of a second mass flow regulator consuming greater than 20 watts of mechanical or electrical power.

20. The heat pump system of claim 19 further comprised of a heat exchanger in thermal communication with the fluid accumulator tank, and wherein the working fluid is operable at a working fluid pressure having a decrease in density per 10 degrees Fahrenheit increase of at least one percent.

21. The heat pump system of claim 20 wherein the fluid accumulator is further comprised of at least one fluid inlet port and at least one fluid discharge port.

22. The heat pump system of claim 21 wherein the at least one fluid inlet port into the fluid accumulator is in fluid communication with the high-side pressure circuit and the at least one fluid discharge port from the fluid accumulator is in fluid communication with the low-side pressure circuit.

23. The heat pump system of claim 22 wherein the at least one fluid inlet port is at least one inch higher than the at least one fluid discharge port.

24. The heat pump system of claim 22 wherein the method of adding working fluid into the at least one thermodynamic cycle is designed to have volumetric displacement of working fluid in the fluid accumulator with working fluid from the high-pressure circuit side having a density of at least one percent lower than the working fluid within the fluid accumulator.

25. The heat pump system of claim 24 wherein the method of adding working fluid into the at least one thermodynamic cycle has an increased rate of fluid addition of at least 5 percent by preheating the temperature of the high-pressure circuit side by at least 10 degrees Fahrenheit greater than the working fluid temperature within the fluid accumulator.

26. The heat pump system of claim 24 further comprised of solar collectors downstream of the one mass flow regulator consuming at least 20 watts of power operable to increase the working fluid temperature by at least 5 degrees Fahrenheit for adding working fluid into the at least one thermodynamic cycle.

27. The heat pump system of claim 24 further comprised of solar collectors downstream of the one mass flow regulator consuming at least 20 watts of power operable to decrease the working fluid temperature by at least 5 degrees Fahrenheit for removing working fluid from the at least one thermodynamic cycle into the fluid accumulator, wherein the solar collector is operable in a thermal emitter mode.

28. The heat pump system of claim 24 further comprised of a thermal source downstream of the one mass flow regulator consuming at least 20 watts of power operable to increase the working fluid temperature by at least 5 degrees Fahrenheit for adding working fluid into the at least one thermodynamic cycle.

29. The heat pump system of claim 24 further comprised of at least one fluid valve control designed to add a circuit containing working fluid or to decrease the temperature of working fluid within the high-side circuit pressure and having a thermal sink downstream of the one mass flow regulator consuming at least 20 watts of power and operable to add working fluid into the at least one thermodynamic cycle high-side circuit pressure.

30. The heat pump system of claim 24 wherein the method of adding working fluid into the at least one thermodynamic cycle has an increased rate of fluid addition of at least 5 percent by cooling the working fluid temperature within the fluid accumulator by at least 5 degrees Fahrenheit.

31. The heat pump system of claim 22 wherein the method of removing working fluid from the at least one thermodynamic cycle is designed to have volumetric displacement of working fluid in the fluid accumulator with working fluid from the high-pressure circuit side having a density of at least one percent greater than the working fluid within the fluid accumulator.

32. The heat pump system of claim 1 further comprised of two overlapping thermodynamic cycles with a first thermodynamic cycle as a power generating thermodynamic loop having a low-side pressure circuit upstream of a power generating expander and a high-side pressure circuit downstream of a power generating expander and a second thermodynamic cycle having a low-side pressure circuit upstream of the one mass flow regulator and a high-side pressure circuit downstream of the one mass flow regulator, wherein the high-side pressure circuit of the second thermodynamic cycle is at least 5 psi greater than the low-side pressure circuit of the first thermodynamic cycle.

33. The heat pump system of claim 1 further comprised of a solid state conversion device including photovoltaic, thermophotovoltaic, thermoelectric, or thermionic cell having a maximum junction temperature; and a backpressure regulator designed to modulate the operating pressure downstream of the one mass flow regulator wherein the operating pressure maintains a phase change working fluid temperature within 5 degrees Fahrenheit of the lesser of solid state conversion device maximum junction temperature or design temperature.

34. The heat pump system of claim 1 further comprising a second thermodynamic cycle having a power generating expander in mechanical communication with the one mass flow regulator circulating the working fluid, and a combustor having combustor exhaust, wherein the at least one thermodynamic cycle is the first thermodynamic cycle and both the first thermodynamic cycle and second thermodynamic cycle have the same working fluid, wherein the heat pump system has a coefficient of performance greater than 1.20, and wherein the combustor is at least one thermal source for the second thermodynamic cycle and the combustor exhaust is at least one thermal source for the first thermodynamic cycle.

35. The heat pump system of claim 34 further comprising a solar collector having the same working fluid as both the first thermodynamic cycle and the second thermodynamic cycle; further comprising a heat exchanger from a low-pressure circuit side of the first thermodynamic cycle to a low-pressure circuit side of the second thermodynamic cycle and wherein the second thermodynamic cycle is void of any heat exchangers having thermal communication between a high-pressure circuit side of second thermodynamic cycle and low-pressure circuit side of second thermodynamic cycle.

36. The heat pump system of claim 35 wherein the working fluid is carbon dioxide, wherein the high-side circuit pressure of the second thermodynamic cycle is greater than 2000 psi, the high-side circuit pressure of the first thermodynamic cycle is greater than 800 psi.

37. The heat pump system of claim 35 wherein the working fluid is carbon dioxide, wherein the high-side circuit pressure of the second thermodynamic cycle is greater than 2700 psi, wherein the high-side circuit pressure of the first thermodynamic cycle is greater than 1200 psi, wherein the high-side circuit pressure of the second thermodynamic cycle is greater than 2.2 times the low-side circuit pressure of the second thermodynamic cycle, and wherein the high-side circuit pressure of the first thermodynamic cycle is at least 5 psi greater than the low-side circuit pressure of the second thermodynamic cycle.

38. The heat pump system of claim 35 further comprised of a heat exchanger to transfer thermal energy from the second thermodynamic cycle low-pressure circuit side to a regenerator of a dehumidification system operable to provide latent cooling, and a heat exchanger from the first thermodynamic cycle high-pressure circuit side operable as a condenser and wherein the first thermodynamic cycle is operable in a cooling mode and the second thermodynamic cycle is operable as a mechanically interconnected power source to the at least one mass flow regulator.

Patent History
Publication number: 20110030404
Type: Application
Filed: Aug 4, 2010
Publication Date: Feb 10, 2011
Applicant: SOL XORCE LLC (Glenview, IL)
Inventor: Michael H. Gurin (Glenview, IL)
Application Number: 12/849,841
Classifications
Current U.S. Class: Utilizing Solar Energy (62/235.1); Flow Line Connected Transfer Fluid Supply And Heat Exchanger (62/434); With Flow Control Or Compressor Details (62/324.6)
International Classification: F25B 27/00 (20060101); F25D 17/02 (20060101); F25B 13/00 (20060101);