Embodiments of the present disclosure relate to geothermal systems configured to facilitate heat exchange. More specifically, embodiments of the disclosure relate to heat-exchange assemblies that utilize coil assemblies to facilitate heat exchange within a heat-exchange cavity.
Conventional closed-loop geothermal heat-exchange systems include a heat pump coupled to a single heat-exchange conduit, or multiple heat-exchange conduits, that extends into the ground, makes a 180 degree turn at a U-bend, and returns to the heat pump. These conventional systems typically require the heat-exchange conduit to extend approximately 200 feet deep for every ton of heating or cooling energy. Thus, for example, a two-ton system may require drilling a borehole approximately 400 feet deep. Other conventional closed-loop geothermal systems may include a large pond-loop structure disposed within a pond or other surface body of water. Accordingly, it would be desirable to be able to perform geothermal heat exchange without needing to drill as deeply as in conventional geothermal systems, and in locations where a surface body of water may not be available.
Embodiments of the disclosure include a geothermal system for facilitating heat exchange. The geothermal system includes a heat-exchange assembly having a coil assembly disposed within a casing.
In an Example 1, a heat-exchange system includes a casing; and a coil assembly disposed within the casing, the coil assembly comprising: a supply inlet configured to receive heat-exchange fluid; a first manifold disposed downstream of the supply inlet, the first manifold comprising a supply conduit and a plurality of manifold outlets; a plurality of exchange conduits, wherein each exchange conduit is coupled, at a first end, to one of the plurality of manifold outlets; a second manifold disposed downstream of the first manifold, the second manifold comprising a return conduit and a plurality of manifold inlets, wherein each exchange conduit is coupled, at a second end, to one of the plurality of manifold inlets; and a return outlet configured to return the heat-exchange fluid.
In an Example 2, the system of Example 1, the casing comprising a perforated polyvinyl chloride (PVC) pipe.
In an Example 3, the system of either of Examples 1 or 2, the casing comprising an annular wall.
In an Example 4, the system of Example 3, the casing further comprising a lower wall at least partially closing a first end of the annular wall.
In an Example 5, the system of either of Examples 3 or 4, the casing further comprising an upper wall at least partially closing a second end of the annular wall.
In an Example 6, the system of any of Examples 3-5, the casing further comprising at least one aperture defined in the annular wall, the at least one aperture being configured to allow water to pass therethrough.
In an Example 7, the system of any of Examples 1-6, further comprising at least one additional coil assembly disposed within the casing.
In an Example 8, the system of Example 7, wherein the at least one additional coil assembly is operatively coupled to the coil assembly.
In an Example 9, the system of Example 8, wherein the coil assembly and the at least one additional coil assembly are operatively coupled in series and/or in parallel.
In an Example 10, the system of any of Examples 1-9, wherein at least one of the first manifold and the second manifold has a length of at least approximately three feet.
In an Example 11, the system of any of Examples 1-10, the plurality of exchange conduits comprising between 75 and 125 exchange conduits.
In an Example 12, the system of Example 11, the plurality of exchange conduits comprising 117 exchange conduits.
In an Example 13, the system of any of Examples 1-12, each of the plurality of exchange conduits having a length of between at least approximately 15 feet and 25 feet.
In an Example 14, the system of Example 13, each of the plurality of exchange conduits having a length of at least approximately 19.5 feet.
In an Example 15, the system of any of Examples 1-14, wherein the plurality of exchange conduits are arranged in a parallel orientation with respect to each other.
In an Example 16, the system of any of Examples 1-15, wherein at least one of the plurality of exchange conduits is coiled with respect to a central axis.
In an Example 17, the system of Example 16, further comprising at least one spacer disposed between adjacent loops of the at least one of the plurality of exchange conduits.
In an Example 18, the system of Example 17, the at least one spacer comprising a plurality of spacers positioned to maintain an at least approximately constant gap between each pair of adjacent loops.
In an Example 19, the system of any of Examples 1-18, wherein the casing is configured to be disposed in a heat-exchange cavity.
In an Example 20, the system of Example 19, the heat-exchange cavity comprising at least one of an underground water storage reservoir, an above-ground water storage reservoir, and a borehole.
In an Example 21, the system of any of Examples 1-20, further comprising an additional casing.
In an Example 22, the system of Example 21, wherein the casing is configured to be disposed in a first heat-exchange cavity, and wherein the additional casing is configured to be disposed at a second heat-exchange cavity.
In an Example 23, the system of Example 22, further comprising a water moving apparatus configured to move water from the first heat-exchange cavity to the second heat-exchange cavity and/or from the second heat-exchange cavity to the first heat-exchange cavity.
In an Example 24, a method includes: positioning a coil assembly within a casing and positioning the casing within a heat-exchange cavity, the coil assembly comprising: a supply inlet configured to receive heat exchange fluid; a first manifold disposed downstream of the supply inlet, the first manifold comprising a supply conduit and a plurality of manifold outlets; a plurality of exchange conduits, wherein each exchange conduit is coupled, at a first end, to one of the plurality of manifold outlets; a second manifold disposed downstream of the first manifold, the second manifold comprising a return conduit and a plurality of manifold inlets, wherein each exchange conduit is coupled, at a second end, to one of the plurality of manifold inlets; and a return outlet configured to return the heat-exchange fluid.
In an Example 25, the method of Example 24, further comprising creating the heat-exchange cavity.
In an Example 26, the method of Example 25, wherein creating the heat-exchange cavity comprises drilling a borehole.
In an Example 27, the method of Example 25, wherein creating the heat-exchange cavity comprises creating an underground water storage reservoir.
In an Example 28, the method of any of Examples 24-27, the casing comprising an annular wall.
In an Example 29, the method of Example 28, the casing further comprising a lower wall at least partially closing a first end of the annular wall.
In an Example 30, the method of either of Examples 28 or 29, the casing further comprising an upper wall at least partially closing a second end of the annular wall.
In an Example 31, the method of any of Examples 28-30, the casing further comprising at least one aperture defined in the annular wall, the at least one aperture being configured to allow water to pass therethrough.
In an Example 32, the method of any of Examples 24-31, further comprising positioning at least one additional coil assembly within the casing.
In an Example 33, the method of Example 32, further comprising operatively coupling the at least one additional coil assembly to the coil assembly.
In an Example 34, the method of Example 33, wherein operatively coupling the at least one additional coil assembly to the coil assembly comprises coupling the coil assembly and the at least one additional coil assembly in series and/or in parallel.
In an Example 35, the method of any of Examples 24-34, wherein at least one of the first manifold and the second manifold has a length of at least approximately three feet.
In an Example 36, the method of any of Examples 24-35, the plurality of exchange conduits comprising between 75 and 125 exchange conduits.
In an Example 37, the method of Example 36, the plurality of exchange conduits comprising 117 exchange conduits.
In an Example 38, the method of any of Examples 24-37, each of the plurality of exchange conduits having a length of between at least approximately 15 feet and 25 feet.
In an Example 39, the method of Example 38, each of the plurality of exchange conduits having a length of at least approximately 19.5 feet.
In an Example 40, the method of any of Examples 24-39, wherein the plurality of exchange conduits are arranged in a parallel orientation with respect to each other.
In an Example 41, the method of any of Examples 24-40, wherein each of the plurality of exchange conduits is coiled with respect to a central axis.
In an Example 42, the method of Example 41, wherein at least one spacer is disposed between adjacent loops of the at least one of the plurality of exchange conduits.
In an Example 43, the method of Example 42, the at least one spacer comprising a plurality of spacers positioned to maintain an at least approximately constant gap between each pair of adjacent loops.
In an Example 44, the method of any of Examples 24-40, further comprising coiling each of the plurality of exchange conduits with respect to a central axis.
In an Example 45, the method of Example 44, further comprising positioning at least one spacer between adjacent loops of at least one of the plurality of exchange conduits.
In an Example 46, the method of Example 45, wherein the step of positioning the at least one spacer comprises positioning a plurality of spacers to maintain an at least approximately constant gap between each pair of adjacent loops.
In an Example 47, the method of any of Examples 24-46, the heat-exchange cavity comprising at least one of an underground water storage reservoir, an above-ground water storage reservoir, and a borehole.
In an Example 48, the method of any of Examples 24-47, further comprising positioning an additional casing within an additional heat-exchange cavity.
In an Example 49, the method of Example 48, further comprising moving water from the heat-exchange cavity to the additional heat-exchange cavity and/or from the additional heat-exchange cavity to the heat-exchange cavity.
In an Example 50, the method of any of Examples 24-49, the casing comprising a perforated polyvinyl chloride (PCV) pipe.
While multiple embodiments are disclosed, still other embodiments of the present disclosure will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the disclosure. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.
While the disclosed subject matter is amenable to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail below. The intention, however, is not to limit the disclosed subject matter to the particular embodiments described. On the contrary, the disclosed subject matter is intended to cover all modifications, equivalents, and alternatives falling within the scope of the disclosed subject matter as defined by the appended claims.
As the terms are used herein with respect to ranges of measurements, “about” and “approximately” may be used, interchangeably, to refer to a measurement that includes the stated measurement and that also includes any measurements that are reasonably close to the stated measurement, but that may differ by a reasonably small amount such as will be understood, and readily ascertained, by individuals having ordinary skill in the relevant arts to be attributable to measurement error, differences in measurement and/or manufacturing equipment calibration, human error in reading and/or setting measurements, adjustments made to optimize performance and/or structural parameters in view of differences in measurements associated with other components, particular implementation scenarios, imprecise adjustment and/or manipulation of objects by a person or machine, and/or the like.
Although the term “block” may be used herein to connote different elements illustratively employed, the term should not be interpreted as implying any requirement of, or particular order among or between, various blocks disclosed herein. Similarly, although illustrative methods may be represented by one or more drawings (e.g., flow diagrams, communication flows, etc.), the drawings should not be interpreted as implying any requirement of, or particular order among or between, various steps disclosed herein. However, certain embodiments may require certain steps and/or certain orders between certain steps, as may be explicitly described herein and/or as may be understood from the nature of the steps themselves (e.g., the performance of some steps may depend on the outcome of a previous step). Additionally, a “set,” “subset,” or “group” of items (e.g., inputs, algorithms, data values, etc.) may include one or more items, and, similarly, a subset or subgroup of items may include one or more items. A “plurality” means more than one.
According to embodiments, a geothermal system is provided for facilitating a heat-exchange process, as described herein. The geothermal system is a closed-loop system that includes one or more heat-exchange assemblies configured to be disposed within a heat-exchange cavity defined in the ground. The heat-exchange assemblies include coil assemblies, having multiple, coiled, lengths of heat-exchange conduit. By implementing aspects of embodiments of the disclosed subject matter, it is estimated that embodiments of the system may facilitate obtaining at least approximately one ton of heating and/or cooling energy for each foot of depth within a region in which temperatures remain approximately constant (e.g., approximately equal to the year-long average air temperature). In embodiments, the heat-exchange assemblies described herein may be positioned such that, during periods of time when the ground water is at its lowest volume, the top of the heat-exchange assembly is at least approximately one foot below the water table. Thus, for example, embodiments of the geothermal system described herein may facilitate obtaining geothermal heat exchange using heat-exchange assemblies buried in boreholes that are drilled to a depth of at least approximately 40 to 60 feet.
According to embodiments, the heat-exchange cavity 112 may include, for example, one or more underground water storage reservoirs, one or more above-ground water storage reservoirs, one or more boreholes, and/or the like. In embodiments, the heat-exchange cavity 112 may include a borehole having a diameter of between at least approximately 20 inches and 36 inches, and a depth of between approximately 15 feet and 100 feet. For example, a borehole may be drilled such that one or more heat-exchange assemblies 106 may be positioned at a depth of between at least approximately 40 feet and 60 feet. The heat-exchange cavity 112 may be at least partially filled with water, aggregate (e.g., grout, gravel, sand, crushed gravel, etc.), and/or the like. In embodiments, the heat-exchange cavity 112 may be, be similar to, include, or be included within, an underground water storage reservoir. Some examples of such underground water storage reservoirs, and their features, are described in U.S. Pat. No. 6,840,710, filed on May 15, 2002, and re-issued on Mar. 6, 2012; U.S. Pat. No. 7,192,218, filed on Feb. 23, 2005, and issued on Mar. 20, 2007; U.S. Pat. No. 7,972,080, filed on Mar. 14, 2008, and issued on Jul. 5, 2011; and U.S. Pat. No. 8,074,670, filed on Sep. 26, 2007, and issued on Dec. 13, 2011, the entirety of each of which is hereby expressly incorporated by reference herein for all purposes.
As depicted in
As is further depicted in
Moreover, as used herein, the terms “side wall,” “lower wall,” “upper wall,” “upward,” and “downward” are used to refer to the specific features to which they refer, but are characterized in the context of the illustrations for clarity and to describe relative orientations of features with respect to other features, and are not intended to imply any particular orientation of the system 100, or absolute (or preferred) orientations of features thereof. Additionally, “downstream” and “upstream” are used to refer to a relative position of components with respect to a fluid flow. Thus, for example, the system 100 may be configured such that heat-exchange fluid flows into the coil assembly via the supply inlet 140, through the first manifold 142, through the exchange conduits, through the second manifold 150, and out through the return outlet 160, in which case a first component is downstream from a second component where the first component is positioned such that the heat-exchange fluid reaches the second component before reaching the first component. Upstream is the opposite of downstream.
The illustrative system 100 shown in
As shown, the heat-exchange assembly 200 includes a casing 204 configured to fit within the heat-exchange cavity 202. A first coil assembly 206 and a second coil assembly 208 are disposed within a cavity 210 defined within the casing 204. As shown, a first supply conduit 212 is coupled to a supply inlet 214 of the first coil assembly 206 and facilitates providing a heat-exchange fluid from a heat pump (not shown) to the first coil assembly 206. A second supply conduit 216 extends from a return outlet 218 of the first coil assembly 206 to a supply inlet 220 of the second coil assembly 208 and facilitates providing heat-exchange fluid from the first coil assembly 206 to the second coil assembly 208. In the illustrated embodiments, a return conduit 222 extends from a return outlet 224 of the second coil assembly 208 to the heat pump.
According to embodiments, any number of coil assemblies may be arranged in series and/or parallel. For example, a heat-exchange assembly 200 may include between one and 15 coil assemblies. In some embodiments, the heat-exchange assembly may include more than 15 coil assemblies. Additionally, heat-exchange assemblies may be configured in any number of different manners such as, for example, such that the return conduit 222 extends through an open space within the coil assemblies 206 and 208 (e.g., the return conduit 222 and/or the supply conduits 212 and 216 may be configured to extend through at least approximately a center region of each coil assembly). In this manner, the conduits 212, 216, and 222 may be protected, and additional diameter does not need to be provided within the casing to accommodate the conduits 212, 216, and 222. Additionally, the supply and return conduits may be configured to pass through at least approximately centrally-located apertures in the upper and/or lower walls of the casing. In this manner, embodiments may facilitate providing a modular system that can be scaled up or down by adding or removing heat-exchange assemblies, each of which may be manufactured in an identical, or at least approximately identical manner. In this manner, also, the supply and return conduits may be manufactured without having to incorporate additional curves and bends for moving the conduits around the loop assemblies and into and out of the casing apertures, thereby potentially saving in manufacturing and/or assembly cost and complexity.
The illustrative implementation shown in
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The illustrative implementation shown in
As described above, embodiments of the subject matter disclosed herein include a coil assembly configured to facilitate heat exchange between a fluid disposed therein and the environment.
As shown, the coil assembly 400 includes a supply inlet 402 configured to receive heat-exchange fluid (e.g., from a heat pump). A first manifold 404 is disposed downstream of the supply inlet 402, and includes a supply conduit 406 and a number of manifold outlets 408. A number of exchange conduits 410 extend between the first manifold 404 and a second manifold 412. In embodiments, the coil assembly 400 may include any number of exchange conduits 410. For example, the coil assembly 400 may include, in embodiments, more than one exchange conduit 410, more than 10 exchange conduits 410, between 10 and 200 exchange conduits 410, between 75 and 125 exchange conduits 410, more than 200 exchange conduits 410, and/or the like. In embodiments, the number of exchange conduits, and/or the dimensions (e.g., width, length, etc.) of each exchange conduit may be configured to achieve desired thermal exchange efficiencies.
For example, in embodiments the coil assembly 400 may include 117 exchange conduits 410, arranged between the first and second manifolds 404 and 412, each of which may be at least approximately three feet in length. Each of the exchange conduits 410 may be any desired length such as, for example, between at least approximately one and thirty feet long, between at least approximately 15 feet and 25 feet, between at least approximately five and twenty feet long, and/or the like. For example, in embodiments, each of the exchange conduits 410 may be at least approximately 18 feet long. In other embodiments, each of the exchange conduits 410 may be at least approximately 19.5 feet. According to embodiments, the exchange conduits 410 may be manufactured using any material suitable for facilitating energy exchange. For example, the exchange conduits 410 may be made of high-density polyethylene (HDPE). In embodiments, the coil assembly 400 may be, be similar to, include, or be included within, a “Geo Hyperloop” available from TEVA Energy, LLC, of Altamonte Springs, Fla.
Each exchange conduit 410 is coupled, at a first end 414 to one of the manifold outlets 408, and is coupled, at a second end 416 to one of a number of manifold inlets 418 defined within the second manifold 412, which operatively couple exchange conduits 410 to a return conduit 420 defined within the second manifold 412. A return outlet 422 is disposed downstream of the second manifold 412 and is configured to facilitate return of the heat-exchange fluid to the heat pump.
According to embodiments, the supply inlet 402 may be disposed at a first end 424 of the first manifold 404, and a second end 426 of the first manifold 404 may be closed. Conversely, a first end 428 of the second manifold 412 (which may be oriented in a similar direction as the first end 424 of the first manifold 404) may be closed, while the return outlet 422 may be disposed at a second end 430 of the second manifold 412. In embodiments, the supply inlet 402 may be disposed at the second end 426 of the first manifold 404, the return outlet 422 may be disposed at the first end 428 of the second manifold 412, and/or the like. In embodiments, the supply inlet 402 and/or the return outlet may be configured to be coupled to connecting conduit (not shown) that facilitates coupling the coil assembly 400 to another coil assembly.
As is further shown in
The illustrative coil assembly 400 shown in
Embodiments of a geothermal system utilizing coil assemblies to facilitate heat exchange are described above.
The method 500 also may include coupling the coil assembly inlet and outlet to a heat pump (block 506), and positioning the coil assembly within a casing (block 508) to create a heat-exchange assembly. In embodiments, the heat-exchange assembly may be, be similar to, include, or be included within, the heat-exchange assembly 106 depicted in
According to embodiments, the method 500 may include any number of other steps in addition to, or in lieu of, the illustrative steps described above. For example, embodiments of the method 500 further include positioning at least one additional coil assembly within the casing and operatively coupling the at least one additional coil assembly to the coil assembly. The coil assembly and the at least one additional coil assembly may be coupled in series, in parallel, or a combination thereof. Embodiments of the method 500 may include positioning an additional casing within an additional heat-exchange cavity. In embodiments, the method 500 may include moving water from the heat-exchange cavity to the additional heat exchange cavity and/or from the additional heat-exchange cavity to the heat-exchange cavity.
As described above, heat-exchange assemblies may include a coil one or more coil assemblies disposed within a casing. In embodiments, more than one (e.g., two or three or any other number) coil assemblies may be disposed within a casing according to any number of different configurations. For example, coil assemblies may be arranged so that at least approximately a desired amount of (or other characteristic of) the heat-exchange fluid-coil assembly surface interface is achieved.
As shown, the first heat-exchange assembly 602 includes a casing 606 at least partially enclosing a cavity 608 within which is disposed a first coil assembly 610a and a second coil assembly 610b. According to embodiments, the coil assemblies 610a and/or 610b may be, be similar to, include, or be included within, the coil assembly 120 depicted in
Similarly, the second heat-exchange assembly 604 includes a casing 642 at least partially enclosing a cavity 644 within which is disposed a first coil assembly 646a and a second coil assembly 646b. The first coil assembly 646a may be positioned concentrically around the second coil assembly 646b. The casing 642 includes an annular wall 648, a lower wall 650 that at least partially closes a first end 652 of the annular wall 648, and an upper wall 654 that at least partially closes a second end 656 of the annular wall 648. The annular wall 648 includes a number of apertures 658 and 660 defined therein, each of which extends from an outer surface 662 of the annular wall 648 to an inner surface 664 of the annular wall 648. In embodiments, the apertures 662 may be configured to receive a water circulation conduit 666 that may facilitate circulating water into and out of the cavity 644 defined within the casing 642. The aperture 660 may be configured to receive a supply conduit 668. An aperture 670 defined in the upper wall 654 may be configured to receive a return conduit 640 and/or to provide access to the cavity 644. An aperture 672 defined in the lower wall 650 may be configured to receive a return conduit 640 that is coupled to the third heat-exchange assembly (not shown), and/or to facilitate drainage of water from within the cavity 644.
In embodiments, the heat-exchange assemblies 602 and 604 may be coupled in series or in parallel, and may be disposed within a heat-exchange cavity 674 having a lower floor 676, upon which the second heat-exchange assembly 604 may be configured to be disposed. A cavity cover 678 may be configured to optionally close an opening 680 to the cavity 674, defined in the surface 682 of the ground.
The illustrative geothermal system 600 shown in
Various modifications and additions can be made to the exemplary embodiments discussed without departing from the scope of the disclosed subject matter. For example, while the embodiments described above refer to particular features, the scope of this disclosure also includes embodiments having different combinations of features and embodiments that do not include all of the described features. Accordingly, the scope of the disclosed subject matter is intended to embrace all such alternatives, modifications, and variations as fall within the scope of the claims, together with all equivalents thereof.