The present technology generally relates to energy storage systems utilizing compressed air and associated systems and methods.
For renewable energy to be cost-competitive, a reliable long-term storage system is required at both macro (e.g., grid) and micro (e.g., residential) levels. It is important to consider not only energy density and efficiency, but also durability, resource utilization, and availability. For example, current renewable energy sources, such as wind and solar, primarily rely on chemical storage systems (e.g., batteries), raising concerns related to resource availability and inefficacies attributable to the multiple energy state transitions needed to store and utilize the generated energy. Therefore, energy storage systems that are reliable, cost-effective, and reduce the number of energy state transitions are needed.
Many aspects of the present technology can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale. Instead, emphasis is placed on illustrating clearly the principles of the present technology. Furthermore, components can be shown as transparent in certain views for clarity of illustration only and not to indicate that the component is necessarily transparent. Components may also be shown schematically.
The present technology is directed to energy storage systems utilizing compressed air that can be used in a variety of settings, such as homes, office buildings, aircraft cabins, etc. Energy storage systems configured in accordance with the present technology are configured to provide and use compressed air for heating, ventilation, and air conditioning (HVAC) applications and non-HVAC applications, such as pneumatically or electrically powering household appliances.
Conventional HVAC systems in residential settings utilize large airducts (e.g., having a diameter of about 8 inches) that extend to multiple rooms, resulting in a network of ducts that occupies a significant amount of space. Moreover, conventional residential HVAC systems utilize electricity to power various components such compressors, heat pumps, coolers, dehumidifiers, etc. that are often associated with high power consumption. In the United States, there is also heavy reliance on foreign resources and non-renewable resources (e.g., minerals), and refrigerants are also becoming increasingly outlawed for their high global warming potential.
The energy storage systems disclosed herein are configured to compress, cool, and dehumidify air from the environment, store the conditioned compressed air, and utilize it in various HVAC and non-HVAC applications. In HVAC applications, the compressed air can be delivered to a room at a desired temperature using an elastocaloric heat pump with nitinol wires arranged along spiraling channels. The compressed air can also be delivered at a desired rate that is tied to an air extraction rate without or with minimal use of electrical components. Heat extracted from the compressed air during cooling stages can be used to provide domestic hot water via hydronics. In non-HVAC applications, the compressed air can be used to provide mechanical forces or generate electricity via piezoelectric elements. For example, in residential settings, the compressed air can be used to pneumatically power various mechanical and electrical household appliances.
By utilizing compressed air, the energy storage systems disclosed herein are expected to reduce the number of energy transitions, and associated inefficiencies and resource concerns, compared to other energy systems. Conventional harvesting of solar energy, for example, requires conversion of solar energy to electricity (e.g., via solar panels), to chemical energy (e.g., stored in batteries), back to electricity (e.g., through the grid), and to mechanical energy (e.g., to power air conditioners). Similarly, conventional harvesting of wind energy requires conversion of wind to mechanical energy (e.g., via wind turbines), to electricity (e.g., via generators), to chemical energy (e.g., stored in batteries), back to electricity (e.g., through the grid), and to mechanical energy (e.g., to power air conditioners). In contrast, compressed air, as described further herein, only requires compression of air (e.g., via a compressor) and conversion to electricity or mechanical energy, depending on the use case. Moreover, compressed air is compatible with other sources of energy (e.g., solar, wind) as compressed air can be used to store any generated energy.
The terminology used in the description presented below is intended to be interpreted in its broadest reasonable manner, even though it is being used in conjunction with a detailed description of certain specific embodiments of the present technology. Certain terms may even be emphasized below; however, any terminology intended to be interpreted in any restricted manner will be overtly and specifically defined as such in this Detailed Description section. Additionally, the present technology can include other embodiments that are within the scope of the claims, but are not described in detail with respect to
Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present technology. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features or characteristics may be combined in any suitable manner in one or more embodiments.
As used herein, the use of relative terminology, such as “about,” “approximately,” “substantially” and the like refer to the stated value plus or minus ten percent. For example, the use of the term “about 100” refers to a range of from 90 to 110, inclusive. In instances in which the context requires otherwise and/or relative terminology is used in reference to something that does not include a numerical value, the terms are given their ordinary meaning to one skilled in the art.
The compressed air displacement ventilation system 160 can include a second air receiver 124 fluidly coupled to the first air receiver 120, a ventilation air delivery assembly 128 fluidly coupled between the second air receiver 124 and the room 140, one or more vortex tubes 130 fluidly coupled between the second air receiver 124 and the room 140, a ventilation air extraction assembly 132 fluidly coupled between the second air receiver 124 and the room 140. In some embodiments, the system 100 can further include a CO2 extraction assembly 134 fluidly coupled between the ventilation air extraction assembly 132 and the air intake 110, and a domestic hot water (DHW) supply 136 fluidly coupled to the room 140.
Each of the first and second air receivers 120, 124 may comprise a storage tank of any size. In some embodiments, the first and/or second air receivers 120, 124 further include one or more sensors (not shown) configured to measure the volume, pressure, influx rate, and/or outflux rate of compressed air stored within. The heat pump 122 can further be fluidly coupled to the ventilation air delivery assembly 128. In some embodiments, the system 100 further includes a first filter 112 positioned at the air intake 110 and/or a second filter 126 positioned between the second air receiver 124 and the ventilation air delivery assembly 128. In some embodiments, the system 100 can omit one or more of the illustrated components, include more than one of the illustrated components, and/or include components not illustrated.
During operation of the system 100, the air intake 110 is adapted to receive air from the environment, and the first filter 112 removes any pollutants, dust, pollen, and/or other airborne particles from the air. The compressor 114 then compresses the air from the air intake 110 and outputs compressed air. In some embodiments, the compressor 114 can be configured to turn on when the sensors in the first and/or second air receivers 120, 124 detect the volume or pressure of stored compressed air reaching a minimum threshold level to restore the needed availability of compressed air. In some cases, the compressed air can be at a high temperature (e.g., up to 200 degrees Celsius) and/or a high humidity level. The cooler 116 can then cool the compressed air from the compressor 114 to output cool compressed (but still moist) air toward the air dryer 118 and direct the heat recovered toward the DHW supply 136 and/or outside of the building. In some embodiments, the heat recovered can be transferred to the DHW supply 136 via water, air, and/or other fluids. The air dryer 118 can then dry the compressed air (e.g., via squeezing moisture out of the compressed air) to output cool, dry, and compressed air to the first air receiver 120. In some embodiments, the air dryer 118 may comprise a hollow membrane air filter. The compressed state of the air can enable the cooling and drying to be performed more efficiently compared to non-compressed air.
The first air receiver 120 can store the cool, dry, and compressed air for either HVAC applications or non-HVAC applications. For HVAC applications, compressed air stored in the first air receiver 120 can be transferred to the heat pump 122 and the compressed air displacement ventilation system 160. The heat pump 122 can output air at a higher or lower temperature than the air stored in the first air receiver 120 toward the ventilation air delivery assembly 128. In some embodiments, the heat pump 122 may comprise an elastocaloric heat pump. Examples of such heat pumps are described in further detail below with respect to
To provide ventilation, the ventilation air delivery assembly 128 can transfer the cool and dry air stored in the second air receiver 124 to the room 140. The second filter 126 can remove any pollutants, dust, pollen, and other airborne particles. In some embodiments, the ventilation air extraction assembly 132 can receive and use compressed air from the second air receiver 124 to remove, extract, or push out air from the room 140. As air is delivered to the room 140, the ventilation air extraction assembly 132 can remove air from the room 140 at an equivalent or similar flow rate to keep the pressure in the room 140 stable. By controlling the rate of removal to be similar or equivalent to the rate of delivery, the pressure in the room 140 can be maintained at a suitable, constant pressure. In some embodiments, the ventilation air extraction assembly 132 may comprise a Venturi vacuum or an air amplifier.
At least a portion of the extracted air can then be sent back to the air intake 110 (or another air intake not shown) through the CO2 extraction assembly 134, which can remove CO2 and/or other fluids from the air. In some embodiments, the CO2 extraction assembly 134 may utilize pressure swing absorption to provide gas separation. By sending the extracted air back to the air intake 110, the system 100 can form an at least partially closed loop that recycles the air and improves the efficiency of the system 100. In some embodiments, the extracted air is pumped to the air intake 110 via the Venturi effect using the ventilation air extraction assembly 132 supplied with compressed air. In some embodiments, the extracted air is pumped to the air intake 110 via an air amplifier (not shown) supplied with compressed air.
To provide heating and cooling, the heat pump 122 can add warm or cool air to the airflow from the second air receiver 124 to the ventilation air delivery assembly 128 such that the air delivered to the room 140 is at a desired temperature. The vortex tubes 130 can further provide rapid cooling to the room (e.g., providing a temperature drop of about 10 degrees Celsius, 15 degrees Celsius, 20 degrees Celsius, etc.) with or without reliance on the heat pump 122. The DHW supply 136 can use heat recovered by the cooler 116 and/or the vortex tubes 130 to provide heated water to the room.
The air delivered to the room 140 by the ventilation air delivery assembly 128 can be filtered, dehumidified, at a desired temperature, and otherwise suitable for human breathing. In some embodiments, the air delivered to the room 140 and the rate of delivery can satisfy local regulations and/or building codes governing air quality. In some embodiments, the amount of air stored in the first and/or second receivers 120, 124 that is dedicated and used for HVAC applications can be determined based at least in part on such regulations and/or building codes, and the remaining portion of the stored air can be used for non-HVAC applications and/or saved for backup.
The air removed from the room 140 by the ventilation air extraction assembly 132 can carry undesirable content away from the room. For example, the ventilation air extraction assembly 132 can remove humid air from a bathroom setting and can remove smelly, oily, greasy, and hot air from a kitchen setting. In some embodiments, the ventilation air extraction assembly 132 can utilize the Venturi effect to improve the extraction process.
Furthermore, the system 100 can derive additional benefits tied to or exclusive to the compressed state of the air. For example, the mechanical dehumidification process employed by the air dryer 118 is expected to operate more effectively with compressed air and with reduced energy consumption compared to other dehumidification processes. The use of compressed air is also expected to reduce the size of ducting required and provide HVAC to multiple individual rooms, reducing the energy consumption compared to other HVAC systems.
Fresh air ventilation can be based on mixing or displacement. A mixing ventilation system (not shown) provides fresh air and a return pathway (e.g., via ducts or transfer grills) to a central air handler. However, the air is mixed, shared, and recycled in a mixing ventilation system, which can result in the distribution of pollutants, pollen, viruses, and other airborne substances throughout the enclosed space. On the other hand, a displacement ventilation system, such as the ventilation system 200 illustrated in
The ventilation system 200 can provide displacement ventilation to the room 140. For example, the ventilation system 200 can include a splitting valve 224, a sensor 250, one or more diffuser valves 227, one or more extraction valves 231, and one or more ventilation air extraction assemblies 232 (e.g., the ventilation air extraction assembly 132 shown in
During operation of the ventilation system 200, compressed air that is filtered, dehumidified at a desired temperature, and otherwise suitable for human breathing can be delivered to the splitting valve 224. For example, the compressed air can be sourced from an air receiver (e.g., the second air receiver 124). In some embodiments, the splitting valve 224 can split the received air stream into multiple streams that simultaneously flow to the diffuser valves 227 and the extraction valve 231 at any desired proportion. In some embodiments, the splitting valve 224 can direct the air stream entirely to either the diffuser valves 227 or the extraction valve 231. In some embodiments, the splitter valve 224 can pulse the air at desired quantities and frequencies. The diffuser valves 227 can release the fresh air directly into the room 140. The ventilation air extraction assembly 232 can extract stale air from the room 140 using the compressed air, as described above with respect to the ventilation air extraction assembly 132 in
The sensor 250 can control the splitting valve 224 based on one or more measurements to increase or decrease the ventilation rate as appropriate automatically. In some embodiments, the sensor 250 may comprise a purely mechanical sensor that measures CO2 level in the room 140 and adjusts the splitting valve 224 to increase the ventilation rate when the measured CO2 level increases and to decrease the ventilation rate when the measured CO2 level decreases. For example, the sensor 250 may comprise an absorptive medium (e.g., zeolite, barlime) that increases in weight by absorbing CO2 in the room 140, and a trigger mechanism configured to trigger ventilation and extraction when the absorptive medium reaches a threshold weight in order to, for example, reduce CO2 concentration in the room 140.
In some embodiments, the amount of airflow directed to the diffuser valves 227 is determined based on local regulations and/or building codes. In some embodiments, the diffuser valves 227 are operably tied together such that when airflow from the splitting valve 224 increases or decreases, the airflow out of individual ones of the diffuser valves 227 increases or decreases by the same rate as or a similar rate to one another, proportionately, at predetermined ratios, etc. This allows any change in ventilation rate to be distributed across the room 140 as desired (e.g., evenly), as opposed to, for example, altering the flowrate of one diffuser valve 227 significantly more or less than the flowrate of another diffuser valve 227. In some embodiments, the individual ones of the diffuser valves 227 can be controlled to output airflow at different rates in order to, for example, provide spot ventilation, spot heating, and/or spot air conditioning.
In some embodiments, the rate of fresh air delivery (e.g., via the diffuser valves 227) can be tied to the rate of air extraction (e.g., via the ventilation air extraction assembly 232) purely mechanically and/or pneumatically. This allows pressure in the room to be maintained without the user of electrical components, reducing overall power consumption of the system 200. Furthermore, tying the extraction rate to the delivery rate can provide a central location for controlling the ventilation rate as only the delivery rate needs to be controlled.
The radiant panel 310 can be made from a material with high thermal conductivity and can be at least partially filled with fluid. In some embodiments, the radiant panel 310 is filled with heated or cooled dehumidified air. In some embodiments, the radiant panel 310 can be attached to a ceiling of a room and covered with or integrated into drywall. In some embodiments, the radiant panel 310 can be attached elsewhere in the room (e.g., on a sidewall, on the floor).
The valve 320 can include a selector component 322 and a pulsing component 324. The selector component 322 can be configured to select between or proportion the airflow from the hot air line 340 and the cold air line 350 to the radiant panel 310. The pulsing components 324 can be configured to pulse the selected airflow to the radiant panel 310 at desired quantities and frequencies. The controller 330 can be configured to control the selector component 322 and/or the pulsing component 324. In some embodiments, the controller 330 may comprise a temperature thermostat that does not include any electrical components. In some embodiments, the system 300 can further include a mechanical humidistat with dew point control configured to control the temperature of the airflow through the radiant panel 310. This can help prevent damage to the drywall, as air in the radiant panel 310 that is below dew point poses a risk of condensation on the drywall. In some embodiments, the system 300 can omit one or more of the illustrated components, include more than one of the illustrated components, and/or include components not illustrated.
During operation of the system 300, the radiant panel 310 can provide radiant heating and/or cooling to the room. In some embodiments, the radiant panel 310 can be operably coupled to and used in conjunction with the system 100 (
Referring first to
Referring next to
For both the first and second heat pumps 400, 420, the channel 410 can have an entry 412 and an exit 414 for fluid flow, although during operation, the direction of fluid flow can reverse as will be described in further detail below. The channel 410 can have a channel diameter D3 that can remain constant or vary along the length of the channel 410.
Referring next to
In some embodiments, the spiral arrangement (
During operation of the first and second heat pumps 400, 420, fluid can be pumped from the entry 412, through the channel 410 and past the wires 440, and out through the exit 414. To provide heating, the fluid can be pumped from a first reservoir (e.g., the first air receiver 120 in
In some embodiments, the channel 410 forms part of a heat exchanger. For example, one or more additional channels (not shown) can be arranged adjacent or proximate the first or second heat pump 400, 420, and a separate fluid stream can be pumped through the one or more additional channels. During operation, heat transfer can occur between the fluid flowing through the first or second heat pump 400, 420 and the separate fluid stream flowing through the one or more additional channels, allowing the separate fluid stream to deliver heating or cooling to the reservoir and/or the room. In some embodiments, the fluid flow through the first or second heat pump 400, 420 and the separate fluid stream are pumped in opposite directions in order to increase the rate of heat exchange therebetween.
Compared to conventional elastocaloric heat pumps, heat pumps configured in accordance with embodiments of the present technology are expected to provide a larger surface area for heat transfer from and to the fluid. Also, by optimizing the arrangement of the wires 440 based on length, thickness, spacing, etc., the corresponding heating and/or cooling of such pumps can be optimized based on the known fluid pressure, while minimizing the quantity of wires 440 required in each channel 410. Furthermore, the bundles 430 are expected to provide manufacturing ease, can be monitored individually, and can be replaced easily depending on the bundle's overall functional state within the channel 410.
One advantage of the compressed air system 100 illustrated in
Non-HVAC mechanical applications of using compressed air can include, for example, (1) toilet flushing (e.g., compressed air-assisted vacuum transit of waste), which would reduce water utilization, (2) pneumatically operated elevators, which may also use passive descent to recover at least a portion of the compressed air used for ascent, and can also serve as a compressed air storage medium (3) providing heated, dry air to dryers, (4) pneumatic waste collection or sanitary systems, which may involve using compressed air and/or a vacuum system (e.g., venturi vacuum) to transport garbage, recyclable materials, and other disposable items from various inlet points to a central collection point, (5) pneumatic sump pumps, (6) optimization of the distribution and coverage of water in sprinkler systems, (7) generating cold plasma, which may help provide a universal cleaning process, and more.
Non-HVAC electrical applications of using compressed air can include using the compressed air to (1) operate a turbine to generate electricity or (2) operate a piezoelectric element to generate electricity. Using either or both options (1) and (2), the compressed air can be used to power any type of electrical appliances, such as blenders, dishwashers, washers, dryers, lighting, televisions, etc. In particular, option (2) of operating a piezoelectric element can reduce or entirely eliminate the need for electrical servicing of such electrical appliances.
During operation of the flashlight 500, a button (not shown) can be pressed by a user to actuate the valve 520 at a predetermined frequency. In some embodiments, the valve 520 can pulse air from the air reservoir 510 at the predetermined frequency to actuate the piston, which in turn operates the piezoelectric element 540. In some elements, the valve 520 can output a pressurized airstream (e.g., at a predetermined frequency) to operate the piezoelectric element 540. The predetermined frequency can be calibrated such that the piezoelectric element 540 generates a stable and appropriate current. The generated current then charges the capacitor 550, which then powers the LED 560 to emit light.
One of ordinary skill in the art will appreciate that the components illustrated in
The above detailed descriptions of embodiments of the technology are not intended to be exhaustive or to limit the technology to the precise form disclosed above. Although specific embodiments of, and examples for, the technology are described above for illustrative purposes, various equivalent modifications are possible within the scope of the technology, as those skilled in the relevant art will recognize. While steps are presented in a given order, alternative embodiments may perform steps in a different order. Moreover, the various embodiments described herein may also be combined to provide further embodiments. Reference herein to “one embodiment,” “an embodiment,” or similar formulations means that a particular feature, structure, operation, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present technology. Thus, the appearances of such phrases or formulations herein are not necessarily all referring to the same embodiment.
For ease of reference, identical reference numbers are used to identify similar or analogous components or features throughout this disclosure, but the use of the same reference number does not imply that the features should be construed to be identical. Indeed, in many examples described herein, identically numbered features have a plurality of embodiments that are distinct in structure and/or function from each other. Furthermore, the same shading may be used to indicate materials in cross section that can be compositionally similar, but the use of the same shading does not imply that the materials should be construed to be identical unless specifically noted herein.
Moreover, unless the word “or” is expressly limited to mean only a single item exclusive from the other items in reference to a list of two or more items, then the use of “or” in such a list is to be interpreted as including (a) any single item in the list, (b) all of the items in the list, or (c) any combination of the items in the list. Where the context permits, singular or plural terms may also include the plural or singular term, respectively. Additionally, the term “comprising” is used throughout to mean including at least the recited feature(s) such that any greater number of the same feature and/or additional types of other features are not precluded. Directional terms, such as “upper,” “lower,” “front,” “back,” “vertical,” and “horizontal,” may be used herein to express and clarify the relationship between various elements. It should be understood that such terms do not denote absolute orientation. Further, while advantages associated with certain embodiments of the technology have been described in the context of those embodiments, other embodiments may also exhibit such advantages, and not all embodiments need necessarily exhibit such advantages to fall within the scope of the technology. Accordingly, the disclosure and associated technology can encompass other embodiments not expressly shown or described herein.
The present application claims the benefit of U.S. Provisional Patent Application No. 63/582,687, filed Sep. 14, 2023, the disclosure of which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63582687 | Sep 2023 | US |