HEAT DISSIPATING DEVICES AND METHODS

Abstract

Heat dissipating devices and methods are disclosed. An example method may include evaporating a liquid working fluid, a resulting vapor phase to absorb heat. The method may also include condensing the vaporized working fluid back to a liquid phase to release the heat to an external environment. The method may also include returning the liquid working fluid back to the evaporation zone.

Description

BACKGROUND

Photovoltaic devices for converting the sun's energy to electrical energy can be used as a supplemental (or even primary) power source. The deployment of photovoltaic devices for commercial and residential electricity consumers is continuing to increase. Due to conversion efficiencies, however, photovoltaic devices often have a large “footprint” and consume valuable “real estate,” meaning that photovoltaic devices are often large in size and can take up substantial space on rooftops and/or at other installations. Therefore, recent development efforts have turned to concentrating photovoltaic devices (CPV), which use optics (e.g., mirrors or lenses) to focus the sun's energy onto smaller photovoltaic substrates. The primary driver behind CPV is cost. The idea for CPV is to use relatively inexpensive optics in conjunction with a small amount of expensive, very high efficiency photovoltaics, providing an overall reduction in the cost to produce electricity.

Concentrating photovoltaic devices convert a portion of the incoming energy from the sun into electricity, with the balance of energy being left to dissipate as heat during operation. If not properly dissipated, this heat can shorten the life span of various components and/or generally result in poor performance of the photovoltaic devices.

Various thermal management systems are available for other heat generating devices, such as computer systems and electronics. These thermal management systems may include a heat sink and/or a cooling fan. The heat sink is positioned adjacent the electronic components generating the most heat to absorb this heat. A cooling fan may be positioned to blow air across the heat sink to dissipate heat into the surrounding environment. While cooling fans can often be effectively implemented in computer systems and other electronic devices because of the controlled environment, photovoltaic devices by their very nature are often located outdoors and thus subject to harsh environmental conditions. Fans may become corroded and/or inoperable. In addition, fans consume energy, counter to the main purpose of photovoltaic technology, and may not provide sufficient cooling for the high temperatures generated by concentrated photovoltaic devices.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1a is a perspective view of an example heat dissipating device.

FIG. 1b is an exploded perspective view of the example heat dissipating device shown in FIG. 1a.

FIG. 1c is a diagrammatic view illustrating operation of the example heat dissipating device shown in FIG. 1a.

FIG. 1d shows an example operating environment for the heat dissipating device shown in FIG. 1a.

FIG. 2a is a perspective view of another example heat dissipating device.

FIG. 2b is an exploded perspective view of the example heat dissipating device shown in FIG. 2a.

FIG. 2c is a diagrammatic view illustrating operation of the example heat dissipating device shown in FIG. 2a.

FIG. 3a is a perspective view of another example heat dissipating device.

FIG. 3b is an exploded perspective view of the example heat dissipating device shown in FIG. 3a.

FIG. 4 is a partial exploded perspective view of another example heat dissipating device.

FIG. 5 is a perspective view of another example heat dissipating device.

FIG. 6 is a side view of another example heat dissipating device.

FIG. 7 is a bottom perspective view of another example heat dissipating device.

FIG. 8 is a perspective view of another example heat dissipating device.

FIGS. 9a-c are side views of still other example heat dissipating devices.

DETAILED DESCRIPTION

Concentrated photovoltaic devices generate large quantities of heat by the very nature of their operation (i.e., focusing the energy of the sun onto a relatively small area). It is noted that the photovoltaic devices do not “generate” heat. Rather, the heat energy represents a portion of the sun's energy that is not converted into electricity. This heat is absorbed by the photovoltaic and dissipated (transferred away from the photovoltaic) by conduction, convection, and radiation. Dissipation of the heat generated by photovoltaic devices may be employed to help prevent damage and enhance operation and lifetime of the devices. It is noted that the heat dissipating devices and methods described herein are not limiting to use with concentrating photovoltaic device, and may be implemented with other heat-generating devices (e.g., computer systems and other electronic devices).

Heat dissipating devices and methods are disclosed. An example device includes an evaporation zone where a working fluid undergoes a change from a liquid phase to a vapor phase. A condensing zone interfaces with a heat sink in thermal communication with an external environment. The working fluid in the vapor phase changes back to the liquid phase in the condensing zone. A wick structure transports the working fluid in the liquid phase to the evaporation zone.

The heat dissipating devices and methods operate in a nearly isothermal heat transfer mode (e.g., offering high thermal conductance), providing efficient heat transfer. The devices and methods also operate in a passive mode, with no moving parts or external power consumption. The devices may be manufactured in diverse and custom forms (e.g., tubular, flat, loop, and groove shapes, to name only a few examples), to fit a variety of geometries, and are relatively low weight. In addition to use in the concentrating photovoltaics field, other applications also include, but are not limited to, electronics cooling, satellite thermal control, temperature calibration, and waste, heat recovery.

Before continuing, it is noted that as used herein, the terms “includes” and “including” mean, but is not limited to, “includes” or “including” and “includes at least” or “including at least.” The term “based on” means “based on” and “based at least in part on.”

FIG. 1a is a perspective view of an example heat dissipating device 100. FIG. 1b is an exploded perspective view of the example heat dissipating device 100 shown in FIG. 1a. The heat dissipating device 100 may include a body 105. The body 105 may be sealed so that a working fluid 110 (see FIG. 1c) is contained therein. In an example, a photovoltaic substrate 101a-b may be about 3 mm by 3 mm with a 50 mm by 50 mm aperture, as shown for example in FIG. 3a (although the substrate can be scaled depending on use), and attached to the front and/or back side of the body 105. Electrical leads 102a-d are shown as these may be used to deliver electrical energy generated by the photovoltaic substrate 101a-b to a storage device (e.g., battery), transmission line (e.g., an electric grid), or end-use (e.g., operating an electrical device).

The body may include a front cover 115a, a back cover 115b, a frame 120, a channel insert 125, and a wick 130. The body 105 may be assembled such that the wick 130 is provided adjacent the channel insert 125 in the frame 120 to form zones for the working fluid 110 (see FIG. 1c).The front cover 115a and back cover 115b may be assembled on the frame 120 to enclose the structure and form the body 105 of the heat dissipating device 100.

FIG. 1c is a diagrammatic view illustrating operation of the example heat dissipating device 100 shown in FIG. 1a. The working fluid 110 may be provided in a boundary 140 formed between an interior wall 121 of the frame 120 and an exterior wall 126 of the channel insert 125. The working fluid 110 may be a liquid which can rapidly undergo phase change from a liquid to a vapor and back to a liquid again. Example working fluids 110 include, but not limited to, helium, nitrogen, ammonia, acetone, methanol, ethanol, water, and toluene, to name only a few examples. The specific working fluid 110 may be selected based on design considerations, such as thermal conductivity and boiling point. During use, the liquid phase working fluid 110 undergoes phase changes to absorb, transport, and release heat.

In an example, the channel insert 125 and wick 130 within the body 105 forms an evaporation zone 145a, where the working fluid 110 undergoes a phase change (illustrated by arrow 150a) from a liquid phase (illustrated by arrow 155a) to a vapor phase (illustrated by arrow 155b). The channel insert 125 and wick 130 within the body 105 also forms a condensation or condensing zone 145b, where the working fluid 110 undergoes a phase change (illustrated by arrow 150b) from the vapor phase 155b to the liquid phase 155a. The condensing zone 145b interfaces with a heat sink 160 in thermal communication with an external environment.

During operation, the photovoltaic substrate 101 may generate heat. This heat may be transferred to the body 105 of the heat dissipating device 100. The working fluid 110 absorbs the heat during the phase change 150a from the liquid phase 155a to the vapor phase 155b. The wick 130 transports the working fluid to the evaporation zone 145a.

The working fluid 110 is then returned to the condensing zone 145b, where the working fluid 110 releases heat as the working fluid 110 undergoes the phase change 150b from the vapor phase 155b to the liquid phase 155a. Heat may be transferred to the heat sink 160 (as illustrated by arrows 165) and dissipated by the heat sink 160 to the external environment.

More specifically, the heat applied to the evaporation zone 145a vaporizes the working fluid 110 to form a saturated or superheated vapor. The vapor pressure drives the vapor through adiabatic section to the condensing zone 145b. The vapor condenses, relating heat to the heat sink 160. Capillary pressure created by the wick 130 serves as a pumping mechanism to move the condensed working fluid back into the evaporation zone 145a. The process is substantially continuous and cyclical during operation.

For purposes of illustration, the heat sink may include aluminum conduction plates. The aluminum conduction plates may have a thermal conductivity of about 500-1200 W/m-K and offers a low resistance (e.g., less than about 15° C./W. The aluminum conduction plates may also be relatively thin (e.g., about 4 mm thick). Use of this materials enables efficient heat removal (e.g., providing a heat flux of about 300 W/cm²) in relatively flat configurations.

The operations shown and described herein are provided to illustrate example implementations. It is noted that the operations are not limited to the ordering shown. Still other operations may also be implemented.

Further operations may include transporting the working fluid 110 in an adiabatic zone 145c with substantially no heat transfer. It is noted that there may be some heat transfer even in the adiabatic zone. However, it is intended that heat transfer occurs largely in the evaporation zone (i.e., heat absorbed by the working fluid) and the condensation zone (i.e., heat released by the working fluid into the heat sink), and that heat is transported by the working fluid in the adiabatic zone.

Still further operations may include transporting heat away from a concentrating photovoltaic device using a high-rate thermodynamic cycle. Yet further operations may include recycling the working fluid through repeated condensation and capillary action.

Before continuing, it should be noted that the examples of the heat dissipating device, the components of the heat dissipating device, and the configuration described above are provided for purposes of illustration, and are not intended to be limiting. Other devices, components, and configurations are also contemplated.

FIG. 1d shows an example operating environment 170 for the heat dissipating device 100 shown in FIG. 1a. In this example, the operating environment 170 includes arrays 175a-d of concentrating photovoltaic devices. Any number of arrays 175a-d may be provided, and each array 175a-d may include any number of photovoltaic substrates 101 mounted on any number of heat dissipating devices 100. Directing sunlight onto the photovoltaic substrates 101 is illustrated by the dashed lines in FIG. 1d. It is noted that the end banks include photovoltaic substrates 101 on one side of the body 105, and the middle banks include photovoltaic substrates 101 on both sides of the body 105 in this example.

The configuration shown in FIG. 1d is only intended to be illustrative and not limiting. In other examples, a sub-support may be provided (e.g., a plastic or metal tray below the arrays). Other structures may also be provided as housing (not shown).

In the example operating environment 170, the sun's rays are reflected by optics (e.g., mirrors) 180 onto the photovoltaic substrate 101. The arrangement and configuration of the optics 180 is such that, in an example, the resulting concentration of the sun's rays onto a given area of the photovoltaic substrate 101 represents an increase of about 300 to 1200 times the energy of direct normal incident light of the sun. It is noted, however, that the heat dissipating device 100 is not limited to any particular optics arrangement and concentration of the sun's energy. The heat dissipating device 100 may be scaled to accommodate various concentrating arrangements.

By way of the above illustration, it is understood that large quantities of heat may be generated, which should be quickly dissipated in order to help ensure continued and efficient conversion of the sun's energy into electricity. In this example, heat generated at the photovoltaic substrate 101 is absorbed by the working fluid 110 in the evaporation zone 145a (see FIG. 1c). The working fluid 110 is then transported to the condensation zone 145b, where the heat is transferred (as illustrated by arrows 165 in FIG. 1c) to the heat sink 160.

The heat sink 160 may include any suitable structure. In FIG. 1d, the heat sink 160 is illustrated as a metal support structure for heat dissipating devices 100 and is provided beneath the optics 180. The heat sink 160 includes a plurality of legs 161a-e, which spread apart and away from the photovoltaic substrate 101 so that heat can be dissipated to the surrounding environment. Other configurations of the heat sink 160 are also contemplated.

FIG. 2a is a perspective view of another example heat dissipating device 200. FIG. 2b is an exploded perspective view of the example heat dissipating device 200 shown in FIG. 2a. FIG. 2c diagrammatic view illustrating operation of the example heat dissipating device 200 shown in FIG. 2a.

The heat dissipating device 200 may include a body 205. The body 205 may be sealed so that a working fluid 210 (see FIG. 2c) is contained therein. In an example, a photovoltaic substrate 201 a-b may be attached to the front and/or back side of the body 205. Electrical leads 202a-d are shown as these may be used to deliver electrical energy generated by the photovoltaic substrate 201a-b.

The body may include a cover 215, a sleeve or frame 220, a wick 225, and a channel insert 230. The body 205 may be assembled such that the channel insert 230 is provided within the wick 225, which is in turn provided in the frame 220. The channel insert 230 has a hollow interior and is open on the top (see FIG. 2c). The cover 215 may be assembled on the frame 220 to enclose the structure and form the body 205 of the heat dissipating device 200.

The working fluid 210 may be provided in a boundary 240 formed within the frame 220. The wick 225 and channel insert 230 within the body 205 forms an evaporation zone 245a, where the working fluid 210 undergoes a phase change (illustrated by arrow 250a) from a liquid phase (illustrated by arrow 255a) to a vapor phase (illustrated by arrow 255b). The wick 225 and channel insert 230 within the body 205 also form a condensation or condensing zone 245b, where the working fluid 210 undergoes a phase change (illustrated by arrow 255b) from the vapor phase 255b to the liquid phase 255a. The condensing zone 245 interfaces with a heat sink 260 in thermal communication with an external environment.

During operation, the photovoltaic substrate 201 may generate heat. This heat may be transferred to the body 205 of the heat dissipating device 200. The working fluid 210 absorbs the heat during the phase change 250a from the liquid phase 255a to the vapor phase 255b. The wick 230 transports the working fluid through the evaporation zone 245a.

The working fluid 210 is then returned to the condensing zone 245b, where the working fluid 210 releases heat as the working fluid 210 undergoes the phase change 250b from the vapor phase 255b to the liquid phase 255a. Heat may be transferred to the heat sink 260 (as illustrated by arrows 265) and dissipated by the heat sink 260 to the external environment. For example, the heat sink 260 may be similar to the heat sink 160 described above with reference to FIG. 1d.

Several examples of other heat dissipating devices will now be described with reference to FIGS. 3-7. It is noted that 300-700 series reference numbers are used in FIGS. 3-7, respectively, to describe similar components as already described above for FIGS. 1 and 2. Therefore the description of each of these components may not be described again below. These additional examples are only illustrative and not intended to be limiting. Still other examples are also contemplated as will be readily appreciated by those having ordinary skill in the art after becoming familiar with the teachings herein.

FIG. 3a is a perspective view of another example heat dissipating device 300. FIG. 3b is an exploded perspective view of the example heat dissipating device 300 shown in FIG. 3a.

The heat dissipating device 300 may include a body 305. The body 305 may be sealed so that a working fluid (not shown) is contained therein. In an example, a photovoltaic substrate 301 may be attached to the body 305 on a dielectric 306. Electrical leads 302a-b are shown as these may be used to deliver electrical energy generated by the photovoltaic substrate 301.

The body may include a cover 315, a frame 320, a channel structure 325 formed in the frame 320, and a wick 330. The body 305 may be assembled such that the wick 330 is provided over the channel structure 325. The channel structure 325. The cover 315 may be assembled on the frame 320 to enclose the structure and form the body 305 of the heat dissipating device 300.

The working fluid may be provided in a boundary 340 formed within the frame 320. The channel structure 325 and wick 330 within the body 305 forms an evaporation zone, where the working fluid undergoes a phase change from a liquid phase to a vapor phase. The channel structure 325 and wick 330 within the body 305 also forms a condensation or condensing zone, where the working fluid undergoes a phase change from the vapor phase to the liquid phase. The condensing zone interfaces with a heat sink 360 in thermal communication with an external environment. In this example, the heat sink 360 is formed as part of the body 305.

FIG. 4 is a partial exploded perspective view of another example heat dissipating device 400. The heat dissipating device 400 may include a body 405. The body 405 may be sealed so that a working fluid (not shown) is contained therein. In an example, a photovoltaic substrate 401 may be attached to the body 405. Electrical leads 402a-b are shown as these may be used to deliver electrical energy generated by the photovoltaic substrate 401.

The body may include a cover or cap 415, a frame 420, a channel structure 425 formed in the frame 420. In this example, the channel structure 425 also functions as a wick to transport condensed fluid back to the evaporation zone behind the photovoltaic substrates. The body 405 may be assembled such that the channel structure 425 slides into the frame 420. The cap 415 may be assembled on the frame 420 to enclose the structure and form the body 405 of the heat dissipating device 400.

The working fluid may be provided in a boundary formed within the frame 420. The channel (and wick) structure 425 within the body 405 forms an evaporation zone, where the working fluid undergoes a phase change from a liquid phase to a vapor phase. The channel structure 425 within the body 305 also forms a condensation or condensing zone. The condensing zone is along the top face of the channel, where heat is dumped to the heat sink fins above. Again, the condensing zone is where the working fluid undergoes a phase change from the vapor phase to the liquid phase. The condensing zone interfaces with a heat sink 460 in thermal communication with an external environment. In this example, the heat sink 460 is formed as part of the body 305.

FIG. 5 is a perspective view of another example heat dissipating device 500. The heat dissipating device 500 may include a body 505. The body 405 may be sealed so that a working fluid (not shown) is contained therein. In an example, a photovoltaic substrate 501 may be attached to the body 505. The body 505 in this embodiment is a simple block that interfaces to the cylindrical heat pipe, allowing simple conductive thermal communication between a flat PV and cylindrical heat pipe, which includes the working fluid and wick. A copper-water cylindrical design is perhaps the simplest and most “commodity-like” heatpipe configuration. The body may be configured similarly to any of the above-described examples, wherein the interior is fluidically connected to a pipe 502, wherein the phase change from liquid to vapor occurs in the body 505 to absorb heat generated by the photovoltaic substrate 501. The vapor is delivered adiabatically through the pipe 502 to a condensing zone formed adjacent the heat sink 560, where the working fluid releases heat while undergoing a phase change from vapor liquid. In this example, the heat sink 560 is formed as a stack of disks. Other structures for the heat sink 560 are also contemplated.

FIG. 6 is a side view of another example heat dissipating device 600. The heat dissipating device 600 may include a body 605. The body 605 is illustrated as a ‘box’ for purposes of simplifying the drawings, and may be sealed so that a working fluid (not shown) is contained therein as described above for other examples. Again, a photovoltaic substrate (601a and 601b) may be attached to the body 605. It is noted that sunlight is reflected onto photovoltaic substrates 601a and 601b by optics not shown in FIG. 6 (refer to FIG. 1d for an example).The body 605 may be configured similarly to any of the above-described examples, wherein the interior is fluidically connected to an interior channel 602, wherein the phase change from liquid to vapor occurs in the body 605 to absorb heat generated by the photovoltaic substrate. The vapor is delivered adiabatically through the pipe 602 to a condensing zone formed within the heat sink 660, where the working fluid releases heat while undergoing a phase change from vapor to liquid. In this example, the heat sink 660 is formed as a support structure for the optics 680 and includes interior channels 603 fluidically connected to the interior channel 602. Fins 604 may also be provided to further enhance heat transfer to the surrounding environment. Other structures for the heat sink 660 are also contemplated.

FIG. 7 is a bottom perspective view of another example heat dissipating device 700. The heat dissipating device 700 may include a body 705. The body 705 is illustrated as a ‘box’ for purposes of simplifying the drawings, and may be sealed so that a working fluid (not shown) is contained therein as described above for other examples. Again, a photovoltaic substrate (not shown) may be attached to the body 705. The body 705 may be configured similarly to any of the above-described examples, wherein the interior is fluidically connected to an interior channel, wherein the phase change from liquid to vapor occurs in the body 705 to absorb heat generated by the photovoltaic substrate. The vapor is delivered adiabatically through the pipe to a condensing zone formed within the heat sink 760, where the working fluid releases heat while undergoing a phase change from vapor liquid. In this example, the heat sink 760 is contoured to the underside of the optics 780 and includes interior channels (not shown) fluidically connected to the interior channel of the body 705. Other structures for the heat sink 760 are also contemplated.

FIG. 8 is a perspective view of another example heat dissipating device 800. This example utilizes a simple rectangular no-wick heat pipe configuration (although the heat pipe can incorporate a wick if desired). The heat pipe 800 may have a top portion 805a-b, and a bottom or tab portion 806a-b. The top and bottom portions may be rectangular in shape, or any other desired shape. The shape may depend at least to some extent on design considerations, such as the layout in a use environment.

The photovoltaic substrates 801a-b and electrical routing 802a-c may be mounted to the body 805a-b of the heat pipe 800, and thus the heat path is as small as possible. In an example, the heat pipe 800 includes liquid and vapor zones within body 805a-b. Heat that is concentrated on the photovoltaic substrates 801a-b spreads very quickly through the rectangle and condenses in the upper section of the heat pipe 800. After condensing, the liquid inside flows back down to the PV area.

The design shown in FIG. 8 is laid out to accommodate the orientation of the photovoltaic substrates 801a-b. The panels may be tilted at an angle determined to optimally collect solar insulation, and thus the photovoltaic substrates 801a-b may be at the bottom of the heat pipe 800 with the liquid flowing to this region by means of gravity.

Wickless heat pipes may be manufactured at low cost. The construction for these heat pipes can be simple. In an example, the liquid is water under higher pressure to allow liquid to evaporate at lower temperatures. The heat pipe body 805 may be made to have any desired alignment features, and thus tolerances, for assembly.

In an example, liquid is provided within separate chambers, such as a single chamber for each body 805a and 805b. In other examples, the heat pipe 800 can be configured as a single large body that may span multiple substrates 805a-b. The particular design may depend at least to some extent on design considerations, such as allowing for differences in the thermal expansion of the optics and support structure. For example, if the optics and/or support structure are manufactured of plastic, then separate heat pipes may function better.

During operation, as heat dissipates on the top of the module, the natural convection coefficient is higher, and thus provides faster heat removal and lower temperatures for better light energy to electrical energy conversion efficiency.

FIGS. 9a-c are side views of still other example heat dissipating devices. The heat dissipating devices 900, 900′, and 900″ include 900-series reference numbers to correspond to parts that have already been described. As can be seen in these figures, the heat dissipating devices may include a body 905 in FIG. 9a, 905′ in FIGS. 9b, and 905″ in FIG. 9c. The body may be sealed so that a working fluid (not shown) is contained therein as described above for FIG. 8. Again, a photovoltaic substrate (901, and 901a-b) may be attached to the body. The body may be configured so that the interior is fluidically connected to an interior channel 902, 902′ and 902″, wherein the phase change from liquid to vapor occurs in the body to absorb heat generated by the photovoltaic substrate. The vapor is delivered adiabatically through the channel 902, 902′ and 902″ to a condensing zone formed within the heat sinks shown according to different variations in FIGS. 9a-c, where the working fluid releases heat while undergoing a phase change from vapor to liquid. In this example, the heat sink extends at least partially below the optics 980, 980′ and 980″ and may also include interior channels fluidically connected to the interior channels 902, 902′ and 902″. Fins 904, 904′ and 904″ may also be provided to further enhance heat transfer to the surrounding environment. The fins may or may not include channel structures therein. Other configurations for the heat sink are also contemplated.

It is noted that the examples shown and described are provided for purposes of illustration and are not intended to be limiting. Still other examples are also contemplated.

Claims

1. A device for dissipating heat, comprising:

an evaporation zone where a working fluid undergoes a change from a liquid phase to a vapor phase;

a condensing zone interfacing with a heat sink in thermal communication with an external environment, the working fluid in the vapor phase changing back to the liquid phase in the condensing zone.

2. The device of claim 1, further comprising an adiabatic zone where the working fluid in the vapor phase is transported without heat transfer.

3. The device of claim 1, further comprising:

a sealed heat pipe body; and

a concentrating photovoltaic conductor assembly attached to the sealed heat pipe body.

4. The device of claim 1, further comprising a wick structure extending substantially adjacent each heat-generating element in a series-arranged photovoltaic conductor assembly, the wick structure to transport the working fluid in the liquid phase to the evaporation zone.

5. The device of claim 1, wherein the heat sink is arranged to substantially conform to an underside of concentrating optics for a concentrating photovoltaic conductor assembly.

6. The device of claim 1, wherein the heat sink is a fin pack.

7. The device of claim 1, wherein the evaporation zone is in a same plane as a photovoltaic conductor assembly.

8. The device of claim 1, wherein the evaporation zone is orthogonal to a photovoltaic conductor assembly.

9. The device of claim 1, further comprising a channel structure defining the evaporation zone and the condensing zone.

10. The device of claim 9, further comprising a wick structure partially wraps around the channel structure.

11. The device of claim 10, wherein the channel structure is positioned between adjacent walls of the wick structure.

12. A method of dissipating heat, comprising:

evaporating a liquid working fluid, a resulting vapor phase to absorb heat;

condensing the vaporized working fluid back to a liquid phase to release the heat to an external environment; and

returning the liquid working fluid back to the evaporation zone.

13. The method of claim 12, further comprising transporting the vaporized working fluid in an adiabatic zone without heat transfer.

14. The method of claim 12, further comprising transporting heat away from a concentrating photovoltaic device using a high-rate thermodynamic cycle.

15. The method of claim 12, further comprising recycling the working fluid through repeated condensation and capillary action.