U.S. patent application number 14/300851 was filed with the patent office on 2014-12-11 for methods and systems for temperature regulation of roof mounted and solar tracker mounted photovoltaic modules.
The applicant listed for this patent is SunEdison Energy India Private Limited. Invention is credited to Nagendra Srinivas Cherukupalli, Sandeep Rammohan Koppikar, Paresh Nasikkar, Marath Prakash.
Application Number | 20140360556 14/300851 |
Document ID | / |
Family ID | 52004409 |
Filed Date | 2014-12-11 |
United States Patent
Application |
20140360556 |
Kind Code |
A1 |
Koppikar; Sandeep Rammohan ;
et al. |
December 11, 2014 |
METHODS AND SYSTEMS FOR TEMPERATURE REGULATION OF ROOF MOUNTED AND
SOLAR TRACKER MOUNTED PHOTOVOLTAIC MODULES
Abstract
One example solar energy system includes a solar tracker, a
plurality of photovoltaic modules mounted to the solar tracker, and
a temperature regulation system. The PV modules are configured to
generate an electrical power output from solar energy incident on
the PV modules. The temperature regulation system includes a
thermal transfer fluid, a fluid pump operable to pump the thermal
transfer fluid, and a plurality of fluid heat exchangers in thermal
communication with the plurality of PV modules and in fluid
communication with the fluid pump. The fluid heat exchangers are
configured to transfer heat from the PV modules to the thermal
transfer fluid.
Inventors: |
Koppikar; Sandeep Rammohan;
(Bangalore, IN) ; Prakash; Marath; (Bangalore,
IN) ; Nasikkar; Paresh; (Bangalore, IN) ;
Cherukupalli; Nagendra Srinivas; (Cupertino, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SunEdison Energy India Private Limited |
Chennai |
|
IN |
|
|
Family ID: |
52004409 |
Appl. No.: |
14/300851 |
Filed: |
June 10, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61833262 |
Jun 10, 2013 |
|
|
|
Current U.S.
Class: |
136/248 ; 165/47;
52/173.3 |
Current CPC
Class: |
F28D 2021/0029 20130101;
Y02E 10/60 20130101; F28F 2240/00 20130101; F28D 20/0034 20130101;
Y02E 60/14 20130101; F28D 20/0052 20130101; Y02B 10/20 20130101;
Y02B 10/70 20130101; F28D 15/00 20130101; H02S 20/23 20141201; F28F
27/00 20130101; H02S 40/44 20141201; Y02E 10/47 20130101; F28F 3/12
20130101; Y02B 10/10 20130101; Y02E 10/50 20130101; Y02E 70/30
20130101; F24S 25/61 20180501 |
Class at
Publication: |
136/248 ;
52/173.3; 165/47 |
International
Class: |
F24D 3/00 20060101
F24D003/00; F24J 2/52 20060101 F24J002/52 |
Claims
1-20. (canceled)
21. A solar energy system comprising: a plurality of photovoltaic
(PV) modules mounted to the roof of a structure, the PV modules
configured to generate an electrical power output from solar energy
incident on the PV modules; and a temperature regulation system
comprising: a thermal transfer fluid; a fluid pump operable to pump
the thermal transfer fluid; and a plurality of fluid heat
exchangers in thermal communication with the plurality of PV
modules and in fluid communication with the fluid pump, the fluid
heat exchangers configured to transfer heat from the PV modules to
the thermal transfer fluid.
22. The solar energy system of claim 21, wherein the PV modules are
mounted to the roof of the structure spaced a distance from the
roof.
23. The solar energy system of claim 21, wherein the PV modules are
mounted to the roof of the structure with substantially no distance
between the PV modules and the roof.
24. The solar energy system of claim 21 further comprising a
secondary heat exchanger in fluid communication with the fluid pump
and the fluid heat exchanger, the secondary heat exchanger
configured to dissipate at least some of the heat contained in the
thermal transfer fluid.
25. The solar energy system of claim 24, wherein the secondary heat
exchanger comprises an array of tubes or coils.
26. The solar energy system of claim 21, wherein the array of tubes
or coils is configured to be buried underground.
27. The solar energy system of claim 21, wherein the array of tubes
or coils is configured for disposition under a floor to provide
underfloor heating.
28. The solar energy system of claim 21, wherein the array of tubes
or coils is configured for disposition in a body of water.
29. The solar energy system of claim 21, wherein the array of tubes
or coils is configured for disposition within walls of a structure
to provide room heating in the structure.
30. The solar energy system of claim 21, wherein the array of tubes
or coils is configured for disposition within walls of a structure
to provide room heating in the structure.
31. The solar energy system of claim 24, wherein the secondary heat
exchanger is configured to indirectly dissipate at least some of
the heat contained in the thermal transfer fluid to a second
fluid.
32. The solar energy system of claim 31, wherein the second fluid
is air.
33. The solar energy system of claim 31, wherein the second fluid
is water.
34. The solar energy system of claim 33, wherein the secondary heat
exchanger is coupled to a water storage tank to provide the water
to the water storage tank after dissipating at least some of the
heat contained in the thermal transfer fluid to the water.
35. The solar energy system of claim 33, wherein the secondary heat
exchanger is coupled to a body of water to provide the water to the
body of water after dissipating at least some of the heat contained
in the thermal transfer fluid to the water.
36. The solar energy system of claim 35, wherein the body of water
is a pool.
37. The solar energy system of claim 31, wherein the secondary heat
exchanger comprises a phase change material based heat
exchanger.
38. The solar energy system of claim 31, wherein the second fluid
is ethylene glycol.
39. The solar energy system of claim 31, wherein the second fluid
is a thermal transfer fluid.
40. The solar energy system of claim 21, wherein the PV modules are
mounted to the roof of the structure recessed into the roof.
41. The solar energy system of claim 22, wherein the PV modules are
configured to reduce a temperature of the roof below the PV
modules.
42. The solar energy system of claim 22, wherein the plurality of
PV modules are operable to generate a greater electrical power
output than similar PV modules that are not in coupled to the
temperature regulation system.
43. The solar energy system of claim 22, wherein the temperature
regulation system is configured to provide at least some of the
heat transferred from the PV modules for use in one of a
residential application, a commercial application, and an
industrial application.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Patent Application
Ser. No. 61/833,262, filed Jun. 10, 2013, which is hereby
incorporated by reference in its entirety.
FIELD
[0002] This disclosure generally relates to temperature regulation
and processing of thermal energy, and more specifically, to methods
and systems for regulating the temperature of roof and/or solar
tracker mounted photovoltaic modules and using the energy
therefrom.
BACKGROUND
[0003] Various devices can benefit from temperature regulation. In
particular, many electronic and/or electrical devices benefit from
temperature control or regulation. For example, photovoltaic (PV)
modules are devices which convert solar energy into electricity.
Some known PV modules convert around 85% of incoming sunlight into
heat. During peak conditions, this can result in a heat-generation
of 850 W/m.sup.2 and PV module temperatures as high as 70.degree.
C. The electrical power produced by PV modules decreases linearly
with increase in module temperature. For example, in bright
sunlight, crystalline silicon PV modules may heat up to
20-30.degree. C. above ambient temperature, resulting in a 10-15%
reduction in power output relative to the rated power output for
the PV module. Moreover, higher PV module temperatures may increase
material degradation, such as thermal fatigue failure of
interconnections between PV cells in the PV module. Accordingly, PV
modules may benefit from reduced temperatures and/or from reducing
a rate of increase in temperature.
[0004] This Background section is intended to introduce the reader
to various aspects of art that may be related to various aspects of
the present disclosure, which are described and/or claimed below.
This discussion is believed to be helpful in providing the reader
with background information to facilitate a better understanding of
the various aspects of the present disclosure. Accordingly, it
should be understood that these statements are to be read in this
light, and not as admissions of prior art.
BRIEF SUMMARY
[0005] According to one aspect of this disclosure, a solar energy
system includes a solar tracker, a plurality of photovoltaic (PV)
modules mounted to the solar tracker, and a temperature regulation
system. The PV modules are configured to generate an electrical
power output from solar energy incident on the PV modules. The
temperature regulation system includes a thermal transfer fluid, a
fluid pump operable to pump the thermal transfer fluid, and a
plurality of fluid heat exchangers in thermal communication with
the plurality of PV modules and in fluid communication with the
fluid pump. The fluid heat exchangers are configured to transfer
heat from the PV modules to the thermal transfer fluid.
[0006] Another aspect of this disclosure is a solar energy system
including a plurality of photovoltaic (PV) modules mounted to the
roof of a structure, and a temperature regulation system. The PV
modules are configured to generate an electrical power output from
solar energy incident on the PV modules. The temperature regulation
system includes a thermal transfer fluid, a fluid pump operable to
pump the thermal transfer fluid, and a plurality of fluid heat
exchangers in thermal communication with the plurality of PV
modules and in fluid communication with the fluid pump. The fluid
heat exchangers are configured to transfer heat from the PV modules
to the thermal transfer fluid.
[0007] Various refinements exist of the features noted in relation
to the above-mentioned aspects. Further features may also be
incorporated in the above-mentioned aspects as well. These
refinements and additional features may exist individually or in
any combination. For instance, various features discussed below in
relation to any of the illustrated embodiments may be incorporated
into any of the above-described aspects, alone or in any
combination.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a perspective view of an example PV module;
[0009] FIG. 2 is a cross-sectional view of the PV module shown in
FIG. 1 taken along the line A--A;
[0010] FIG. 3 is a cross-sectional view of a heat exchanger;
[0011] FIG. 4 is a temperature regulation system including the heat
exchanger shown in FIG. 3;
[0012] FIG. 5 is a cross-sectional illustration of an assembly
including a heat exchanger attached to a PV module;
[0013] FIG. 6 is a top view of an assembly including a heat
exchanger integrated into a PV module;
[0014] FIG. 7 is a cross sectional view of the assembly shown in
FIG. 6 taken along the line A-A in FIG. 6;
[0015] FIG. 8 is a top view of a stand-alone heat exchanger;
[0016] FIG. 9 is a cross sectional view of heat exchanger shown in
FIG. 8 taken along the line B-B in FIG. 8;
[0017] FIG. 10 is a top view of a heat exchanger including a
plurality of plastic spacers;
[0018] FIG. 11 is a cross sectional view of heat exchanger shown in
FIG. 10 taken along the line C-C in FIG. 10;
[0019] FIG. 12 is a cross sectional view of a connection assembly
for use as an inlet and/or outlet for a heat exchanger;
[0020] FIG. 13 is a heat exchanger coupled to a device;
[0021] FIG. 14 is a temperature regulation system including an
in-ground secondary heat exchanger;
[0022] FIG. 15 is another temperature regulation system including
an in-ground secondary heat exchanger;
[0023] FIG. 16 is a temperature regulation system with a secondary
heat exchanger in a body of water;
[0024] FIG. 17 is a temperature regulation system with a secondary
heat exchanger to provide hot water;
[0025] FIG. 18 is a temperature regulation system with a secondary
heat exchanger to provide hot air;
[0026] FIG. 19 is a temperature regulation system with a PCM based
storage and heat exchanger to provide hot water;
[0027] FIG. 20 is a temperature regulation system with a secondary
heat exchanger to provide hot water to a hot water storage
tank;
[0028] FIG. 21 is a temperature regulation system configured to
provide hot water to coils for underfloor heating;
[0029] FIG. 22 is a temperature regulation system with a secondary
heat exchanger to provide hot water to a pool;
[0030] FIG. 23 is an assembly of PV modules including heat
exchangers;
[0031] FIG. 24 is another exemplary assembly of PV modules
including heat exchangers;
[0032] FIG. 25 is an exploded view of the inner and outer layers of
an example heat exchanger;
[0033] FIG. 26 is a partial view of the assembled heat exchanger
shown in FIG. 25;
[0034] FIG. 27 is a view of the heat exchanger shown in FIG. 25
attached to the bottom surface of a solar panel;
[0035] FIG. 28 is a graph of output power of fixed tilt cooled and
uncooled PV modules as a function of the time of day;
[0036] FIG. 29 is a side elevation view of an exemplary system
including a PV module and heat exchanger mounted on a solar
tracker;
[0037] FIG. 30A is a graph of output power of cooled and uncooled
PV modules as a function of the angle of incidence of light on the
PV modules;
[0038] FIG. 30B is a graph of short circuit current of cooled and
uncooled PV modules as a function of the angle of incidence of
light on the PV modules;
[0039] FIG. 30C is a graph of open circuit voltage of cooled and
uncooled PV modules as a function of the angle of incidence of
light on the PV modules;
[0040] FIG. 30D is a graph of the temperature of cooled and
uncooled PV modules as a function of the angle of incidence of
light on the PV modules;
[0041] FIG. 31 is a diagram of an example PV module mounted to a
roof of a building;
[0042] FIG. 32 is a diagram of a PV module flush mounted on the
roof of a building;
[0043] FIG. 33 presents temperature measurements obtained for an
uncooled PV module and a cooled PV module installed various
distances above a roof;
[0044] FIG. 34 is a temperature regulation system including a roof
mounted PV module and heat exchanger; and
[0045] FIG. 35 is a graph of the increase in PV module power output
and the increase in water temperature, both as a function of the
flow rate of the water through a heat exchanger.
[0046] Like reference symbols in the various drawings indicate like
elements.
DETAILED DESCRIPTION
[0047] The embodiments described herein generally relate to
temperature regulation and control. More specifically, embodiments
described herein relate to methods and systems for regulating and
controlling temperature using a heat exchanger. Specific
embodiments are described herein with reference to photovoltaic
(PV) modules. However, the teachings of the present disclosure may
be applied to any device that may benefit from enhanced temperature
regulation. Moreover, although various embodiments will be
discussed with respect to cooling a device, it should be understood
that the embodiments described herein may additionally, or
alternatively, be used to heat a device with which they are
used.
[0048] Referring initially to FIGS. 1 and 2, a PV module is
indicated generally at 100. A perspective view of PV module 100 is
shown in FIG. 1. FIG. 2 is a cross sectional view of PV module 100
taken at line A-A shown in FIG. 1. PV module 100 includes a solar
panel 102 and a frame 104 circumscribing solar panel 102.
[0049] Solar panel 102 includes a top surface 106 and a bottom
surface 108 (shown in FIG. 2). Edges 110 extend between top surface
106 and bottom surface 108. In this embodiment, solar panel 102 is
rectangular shaped. In other embodiments, solar panel 102 may have
any suitable shape.
[0050] As shown in FIG. 2, this solar panel 102 has a laminate
structure that includes several layers 118. Layers 118 may include
for example glass layers, non-reflective layers, electrical
connection layers, n-type silicon layers, p-type silicon layers,
and/or backing layers. In other embodiments, solar panel 102 may
have more or fewer, including one, layer 118, may have different
layers 118, and/or may have different types of layers.
[0051] As shown in FIG. 1, frame 104 circumscribes solar panel 102.
Frame 104 is coupled to solar panel 102, as best seen in FIG. 2.
Frame 104 assists in protecting edges 110 of solar panel 102. In
this embodiment, frame 104 is constructed of four frame members
120. In other embodiments frame 104 may include more or fewer frame
members 120.
[0052] Exemplary frame 104 includes an outer surface 130 spaced
apart from solar panel 102 and an inner surface 132 adjacent solar
panel 102. Outer surface 130 is spaced apart from and substantially
parallel to inner surface 132. In this embodiment, frame 104 is
made of aluminum. More particularly, in some embodiments frame 104
is made of 6000 series anodized aluminum. In other embodiments,
frame 104 may be made of any other suitable material providing
sufficient rigidity including, for example, rolled or stamped
stainless steel, plastic, or carbon fiber.
[0053] FIG. 3 is a simplified cross-sectional view of a heat
exchanger 300 according to one embodiment of the present
disclosure. Heat exchanger 300 includes an inner layer 302, a fluid
layer 304, and an outer layer 306. In this embodiment, fluid layer
304 includes a chamber 305 and one or more spacers or spacing
material (not shown in FIG. 3) to maintain a substantially
consistent separation between inner and outer layers 302 and 306.
The spacers are connected to inner layer 302 and outer layer 306
to, among other things, prevent bulging of inner or outer layer 302
or 306 when fluid is pumped into chamber 305 of fluid layer 304.
Seals 308 connect inner and outer layers 302 and 306 to provide a
substantially water tight seal around fluid layer 304, and more
specifically around chamber 305. Thus, a heat transfer fluid, such
as water, oil, ethylene glycol, etc., may flow through fluid layer
304 to extract heat from a device with which heat exchanger 300 is
used, without the fluid contacting the device. In some embodiments,
seals 308 may be, additionally or alternatively, spacers or spacing
material. Moreover, in some embodiments, seals 308 may be
integrally formed with inner layer 302 and/or outer layer 306.
[0054] Inner layer 302 is the portion of heat exchanger 300 that
will be in contact with the device to be temperature regulated by
heat exchanger 300. Accordingly, inner layer 302 is made from a
material having relatively high thermal conductivity, such as
aluminum, copper, etc. Moreover, the material for inner layer 302
is selected to conform reasonably well to the surface of the device
with which it will be used in order to provide sufficient thermal
contact or thermal communication with the surface of the device. In
this embodiment, inner layer 302 comprises a sheet that is suitably
made of metal. In other embodiments, inner layer 302 may be an
aluminum sheet.
[0055] The thickness of inner layer 302 may be varied, e.g., to
suit different uses. Thicker sheets may be used to provide
increased rigidity and thermal transfer, but with a corresponding
decrease in flexibility and/or conformability. In some embodiments,
inner layer 302 is a thin, metal foil. In one exemplary embodiment,
inner layer 302 is a metal foil having a thickness of about 0.1
millimeter. In another embodiment, inner layer 302 is an aluminum
foil having a thickness of about 300 micrometers. Other embodiments
may use thicker or thinner metal foils. The use of thinner
materials for inner layer 302 may increase the flexibility of heat
exchanger 300, reduce the weight of heat exchanger 300, and/or
permit it to conform to more irregular shaped devices. In general,
inner layer 302 may be constructed from any thermally conductive
material of sufficient strength and impermeability to retain a heat
transfer fluid within heat exchanger 300.
[0056] Outer layer 306 is the portion of heat exchanger 300
opposite the side of heat exchanger 300 that will be in contact
with the device to be temperature regulated by heat exchanger 300
(i.e., opposite inner layer 302). In some embodiments, outer layer
306 is made of a material having relatively high thermal
conductivity, such as a metal sheet or a metal foil, to permit heat
to radiate from fluid layer 304 through outer layer 306. In other
embodiments, outer layer is fabricated from a material that is not
particularly thermally conductive, such as a plastic sheet or film.
The thickness of outer layer 306 may be varied to suit different
uses. Thicker sheets may be used to provide increased rigidity and
thermal transfer, but with a corresponding decrease in flexibility
and/or conformability. In some embodiments, outer layer 306 is a
thin, metal foil. In other embodiments, outer layer 306 is a thin
sheet that is suitably made of plastic. The use of thinner
materials for outer layer 306 may increase the flexibility of heat
exchanger 300, reduce the weight of heat exchanger 300, and/or
permit it to conform to more irregular shaped devices. In general,
outer layer 306 may be made of any material of sufficient strength
and impermeability to retain a heat transfer fluid within heat
exchanger 300. In one example embodiment, outer layer 306 is a
transparent acrylic sheet having a thickness of about three
millimeters.
[0057] FIG. 4 is a simplified diagram of a closed loop temperature
control or regulation system 400 including heat exchanger 300 (heat
exchanger may alternatively be referred to as a meshplate). Heat
exchanger 300 is coupled to a device 402 that may benefit from
temperature regulation provided by heat exchanger. In this
embodiment, device 402 is a device, such as PV module 100, that
generates heat and heat exchanger 300 is used to reduce the
temperature and/or slow the rise in temperature of device 402. In
other embodiments, heat exchanger 300 may be used to increase the
temperature of device 402 and/or slow the decrease in temperature
of device.
[0058] In this embodiment, a pump 404 pumps a thermal transfer
fluid (e.g., a coolant) to an inlet (not shown in FIG. 4) of heat
exchanger 300. The transfer fluid passes into chamber 305 of fluid
layer 304 through the inlet. Within chamber 305, the thermal
transfer fluid draws off heat from device 402, via thermal
conduction through connection of inner layer 302 to device 402. The
thermal transfer fluid exits heat exchanger 300 via an outlet (not
shown in FIG. 4) and is directed to a fluid heat exchanger 406
(also referred to herein as a secondary heat exchanger). As will be
described in more detail below, fluid heat exchanger 406 may be any
heat exchange device suitable for extracting the heat carried by
the thermal transfer fluid. For example, fluid heat exchanger may
be a radiator, an extended length of thermally conductive conduit,
a condenser, etc. Moreover, in some embodiments fluid heat
exchanger 406 may be part of another system, such that heat
extracted from thermal transfer fluid may be used by the other
system. In one example embodiment fluid heat exchanger 406 is a
radiator used to warm the air inside a structure. In another
embodiment fluid heat exchanger 406 is used to heat water.
[0059] As will be readily understood by those of ordinary skill in
the art, system 400 may, additionally or alternatively, be used to
heat device 402. In such embodiments, thermal transfer fluid having
a temperature greater than device 402 is pumped by pump 404 to heat
exchanger 300. Within chamber 305, the thermal transfer fluid loses
its heat to device 402, via conduction through inner layer 302.
Fluid heat exchanger 406 then increases the temperature of the heat
transfer fluid before pump 404 returns the fluid to heat exchange
device 300. A single system 400 may be used to selectively heat or
cool device 402 through use of a dual purpose fluid heat exchanger
406 or separate, selectable, fluid heat exchangers 406: one for
heating the thermal fluid and another for cooling the thermal
fluid. Thus, device 402 may be cooled by system 400 when
temperatures are relatively high, and warmed by system 400 when
temperatures are relatively cool.
[0060] A controller 408 controls operation of system 400. More
specifically, controller 408 controls operation of system 400 to
obtain a desired amount of cooling and/or heating of device 402. In
some embodiments, controller 408 may monitor a temperature of
device 402 with a sensor (not shown). Other embodiments do not
include controller 408. In this embodiment, controller 408 is
configured to control operation of pump 404. Controller 408 may
operate pump 404 continuously, intermittently, and/or may pulse
pump 404 to achieve a desired heating/cooling of device 402. In
some embodiments, controller 408 may additionally, or
alternatively, control operation of fluid heat exchanger 406 and/or
heat exchanger 300. In still other embodiments, controller 408 may
also control operation of device 402. For example, controller 408
may be a PV system controller that controls operation of a direct
current (DC) to alternating current (AC) power converter extracting
power from a PV module device 402.
[0061] In this embodiment, controller 408 is configured to operate
pump 404 other than continuously. Controller 408 can operate pump
404 at a duty cycle of less than 100% in some embodiments because
system 400 cools device 402 faster than the device 402 heats up
when pump 404 is turned off (i.e., not pumping). In one example,
device 402 is PV module 100 and system 400 is operable to cool down
the PV module 100 twice as fast as the PV module 100 heats up due
to the high heat capacity and low thermal conductivity of PV module
100. In this example, controller 408 may operate pump 404 with a
duty cycle between 30% and 50%. This may provide significant energy
gain while reducing pumping costs and coolant usage.
[0062] Controller 408 may be any suitable controller, including any
suitable analog controller, digital controller, or combination of
analog and digital controllers. In some embodiments, controller 408
includes a processor (not shown) that executes instructions for
software that may be loaded into a memory device. The processor may
be a set of one or more processors or may include multiple
processor cores, depending on the particular implementation.
Further, the processor may be implemented using one or more
heterogeneous processor systems in which a main processor is
present with secondary processors on a single chip. In another
embodiment, the processor may be a homogeneous processor system
containing multiple processors of the same type. In some
embodiments, controller 408 includes a memory device (not shown).
As used herein, a memory device is any tangible piece of hardware
that is capable of storing information either on a temporary basis
and/or a permanent basis. The memory device may be, for example,
without limitation, a random access memory and/or any other
suitable volatile or non-volatile storage device. The memory device
may take various forms depending on the particular implementation,
and may contain one or more components or devices. For example, the
memory device may be a hard drive, a flash memory, a rewritable
optical disk, a rewritable magnetic tape, and/or some combination
of the above. The media used by memory device also may be
removable. For example, without limitation, a removable hard drive
may be used for the memory device.
[0063] FIG. 5 is a cross-sectional illustration of an assembly
including heat exchanger 300 attached to PV module 100.
[0064] In this embodiment, solar panel 102 includes a front glass
500, solar cells 502 surrounded by an encapsulant 504, and a back
sheet 506. In this embodiment, the encapsulant 504 comprises
ethylene vinyl acetate (EVA). In other embodiments, any other
suitable encapsulant may be used. In this embodiment, back sheet
506 is a polyvinyl fluoride (PVF) material. In other embodiments,
back sheet 506 may be any other suitable back sheet material or a
laminate of materials, including, for example a laminate of PVF
surrounding a polyester material.
[0065] Thermal transfer fluid enters heat exchanger 300 via inlet
508 and passes through chamber 305 to outlet 510. A spacer 512 is
contained within chamber 305. Spacer 512 separates inner and outer
layers 302 and 306 and slows the flow of the thermal transfer fluid
through chamber 305 to permit the thermal transfer fluid to absorb
heat from solar panel 102. In this embodiment, spacer 512 includes
a mesh. More specifically, mesh is a woven-plastic mesh. In other
embodiments, spacer 512 may include a non-woven mesh, a metal mesh,
a sponge, spacer strips, capillary tubes, or some combination of
the above. In this embodiment, mesh 512 is attached to inner and
outer layers 302 and 306 and substantially fills chamber 305. In
one exemplary embodiment, mesh 512 is approximately 300 micrometers
thick.
[0066] Heat exchanger 300 may be permanently or semi-permanently
integrated into solar panel 102, or may be a standalone component
that may be removably attached to a device. A standalone heat
exchanger 300 may be coupled to device 402 by any suitable means to
provide a thermally connection between inner layer 302 and a
surface of device 402. In some embodiments, heat exchanger 300 is
connected to device 402 using a thermally conductive adhesive,
including for example a double-sided, thermally conductive
tape.
[0067] FIG. 6 is a top view of an assembly 600 including heat
exchanger 300 integrated into PV module 100. FIG. 7 is a cross
sectional view of assembly 600 taken along the line A-A in FIG.
6.
[0068] In assembly 600, heat exchanger 300 is integrally formed
with PV module 100 and does not need to be separately adhered to PV
module 100. Moreover, heat exchanger 300 uses backsheet 506 of PV
module 100 as inner layer 302. Spacer strips 602 extend between
inner layer 302 (i.e., backsheet 506) and outer layer 306 to define
cavity 305. Although not shown in FIGS. 6 and 7, cavity 305 also
includes spacer 512. In this embodiment, spacer 512 is a metallic
mesh 512 capable of withstanding the heat and pressure of
lamination with PV module 100. In other embodiments, cavity 305 may
include any other suitable filler and/or spacer. Outer layer 306
extends around spacer strips 602 to adhere heat exchanger 300 to PV
module 100 and facilitate sealing cavity 305.
[0069] FIG. 8 is a top view of a stand-alone heat exchanger 300 of
one embodiment. FIG. 9 is a cross sectional view of heat exchanger
300 taken along the line B-B in FIG. 8. The embodiment of heat
exchanger 300 shown in FIGS. 8 and 9 is not integrally formed with
any device and may be attached to any device, such as PV module
100, by any suitable type of attachment. In this embodiment, two
sets of seals 308 are included around spacer 512.
[0070] FIGS. 10 and 11 show an example heat exchanger 300 in which
spacer 512 includes a parallel arrangement of plastic spacers. FIG.
10 is a top view, and FIG. 11 is a cross sectional view taken along
the line C-C in FIG. 10. The illustrated heat exchanger 300
provides a serpentine fluid flow through heat exchanger 300. The
serpentine fluid flow provides increased heat transfer as compared
to non-serpentine fluid flows. Heat exchanger 300 shown in FIGS. 10
and 11 may be integrated into a device or may be a standalone heat
exchanger 300. The gap between adjacent spacers may be any suitable
distance that ensures good fluid flow within the system to improve
heat transfer and reduce bloating issues.
[0071] FIGS. 25, 26 and 27 show an example heat exchanger 300
including parallel chambers 305 through which heat transfer fluid
passes. FIG. 25 is an exploded view of the inner and outer layers
302 and 306. FIG. 26 is a partial view of assembled inner and outer
layers 302 and 306. FIG. 27 is a view of the example heat exchanger
300 attached to the bottom surface 108 of a solar panel 102.
Although three and four chambers 305 are shown in FIGS. 25-27, heat
exchanger 300 may include any suitable number of chambers 305,
whether more or fewer.
[0072] In this embodiment, inner layer 302 is a substantially flat
sheet, outer layer 306 is a corrugated sheet, and both inner layer
302 and outer layer 306 are aluminum. Alternatively, inner and
outer layers 302, 306 may be any other suitable thermally
conductive material. Moreover, inner layer 302 and outer layer 306
may be made of different materials. Inner layer 302 is attached to
outer layer 306 by spot welds 2500 between chambers 305.
Alternatively or additionally, inner layer 302 may be attached to
outer layer 306 by any suitable connector(s), including rivets,
nuts and bolts, adhesives, etc. Heat exchanger 300 shown in FIGS.
25-27 may be integrated into a device or may be a standalone heat
exchanger 300.
[0073] In one example, a heat exchanger 300 shown in FIGS. 25-27
was used to cool PV module 100 positioned in a fixed position
(i.e., without solar tracking). A twenty liter per hour (LPH) flow
rate of water fluid through heat exchanger 300 produced a 12% power
gain and output water that was 2.degree. C. hotter than the input
water. A 2.5 LPH flow produced a 3% power gain in PV module 100 and
output water that was 11.degree. C. hotter than the input water.
Thus, by varying the rate of flow of water, or other thermal
transfer fluid, through heat exchanger 300, the amount of cooling
(and accordingly, the power gain) and the temperature gain of the
water may be varied. FIG. 28 is a graph comparing the maximum power
output of PV module 100 with the heat exchanger 300 (the "cooled
module") to the maximum power output of an uncooled PV module 100
as a function of the time of day. FIG. 35 graphs the increase in
power output of the PV module 100 and the increase in temperature
of the water used for cooling (i.e., outlet temperature minus inlet
temperature) both as a function of the flow rate of water through
the heat exchanger 300.
[0074] FIG. 12 is a partially schematic cross section of a suitable
connection assembly 1200 for use at inlet 508 and/or outlet 510 of
any embodiment of heat exchanger 300. Assembly 1200 includes a male
component 1202 positioned inside exchanger 300 and extending
through outer layer 306. A female component 1204 is positioned
outside of heat exchanger 300 adjacent outer layer 306. Female
component 1204 receives and surrounds the portion of male component
1202 that extends outside of heat exchanger 300. A portion of outer
layer 306 is trapped between female component 1204 and male
component 1202. Tubing 1206, used to transport thermal transfer
fluid to and from heat exchanger 300, is inserted into female
component 1204 to couple tubing 1206 to male component 1202.
Assembly 1200 forms a liquid tight connection to heat exchanger
300. Thermal transfer fluid (e.g., a suitable coolant) may be
transferred, via tubing 1206 and assembly 1200, from outside of
heat exchanger 300 to the interior of heat exchanger 300, and vice
versa.
[0075] FIG. 13 is a partially schematic view of heat exchanger 300
coupled to a device 1300. The device may be any suitable device
that may benefit from temperature regulation provided by heat
exchanger 300.
[0076] FIGS. 14-22 illustrate various embodiments of closed loop
temperature control or regulation system 400 including heat
exchanger 300. It should be understood that any of the embodiments
of heat exchanger 300 described above may be used in the
temperature regulation systems 400 shown in FIGS. 14-22. At least
some of the temperature regulation systems 400 described herein
utilize thermal energy produced by the PV modules 100 for other
useful purposes and thus are sometimes referred to herein as solar
energy systems.
[0077] FIG. 14 is a simplified diagram of a temperature regulation
system 400 including heat exchanger 300 coupled to PV module 100
and an in-ground secondary heat exchanger 1400. The secondary heat
exchanger 1400 is a fluid retaining tank positioned underground.
The secondary heat exchanger 1400 may be made of metal, plastic, or
any other suitable material or combination of materials. Fluid from
the secondary heat exchanger 1400 is pumped through heat exchanger
300 by pump 404. The heated fluid exiting the heat exchanger 300
flows back to the secondary heat exchanger 1400. The heat stored in
the fluid in secondary heat exchanger 1400 is dissipated through
the secondary heat exchange 1400 into the ground. The dissipation
of heat into the ground occurs particularly at times when the fluid
is not being used to cool the PV module 100, such as a night. The
secondary heat exchanger 1400 is buried a depth "h" below the
ground level 1402. In some embodiments, h is a depth below ground
level 1402 at which the annual ground temperature is relatively
constant. Alternatively, the depth h may be any other suitable
depth. In some embodiments, additives (e.g., charcoal, metal dust,
etc.) may be added to the soil surrounding the secondary heat
exchanger 1400 to enhance the heat transfer between the secondary
heat exchanger 1400 and the ground. In still other embodiments
secondary heat exchanger 1400 may be positioned on or above ground
level.
[0078] FIG. 15 is a simplified diagram of another temperature
regulation system 400 including heat exchanger 300 coupled to PV
module 100 and an in-ground secondary heat exchanger 1500. The
secondary heat exchanger 1500 is a serpentine array of tubes
positioned underground. The secondary heat exchanger 1500 may be
made of metal, plastic, or any other suitable material or
combination of materials. The heated fluid exiting the heat
exchanger 300 flows through the secondary heat exchanger 1500
before returning to the heat exchanger 300. At least some of the
heat stored in the fluid is dissipated through the secondary heat
exchange 1500 into the ground. The secondary heat exchanger 1500 is
buried a depth "h" below the ground level 1402. In some
embodiments, h is a depth below ground level 1402 at which the
annual ground temperature is relatively constant. Alternatively,
the depth h may be any other suitable depth. In some embodiments,
additives may be added to the soil surrounding the secondary heat
exchanger 1500 to enhance the heat transfer between the secondary
heat exchanger 1500 and the ground. Although shown as a vertical
array of tubes, secondary heat exchanger 1500 may be a vertical
array of tubes, a horizontal array of tubes, an array of coils, an
array of vertical and horizontal tubes, an array of arbitrary
angled tubes, and/or any suitable combination of horizontal tubes,
vertical tubes, arbitrary angled tubes, and coils.
[0079] FIG. 16 is a simplified diagram of another temperature
regulation system 400 including heat exchanger 300 coupled to PV
module 100 and a secondary heat exchanger 1600. The secondary heat
exchanger 1600 is a serpentine array of tubes disposed in a body of
water 1602. The secondary heat exchanger 1600 may be made of metal,
plastic, or any other suitable material or combination of
materials. The heated fluid exiting the heat exchanger 300 flows
through the secondary heat exchanger 1600 before being returned by
pump 404 to the heat exchanger 300. At least some of the heat
stored in the fluid is dissipated through the secondary heat
exchange 1600 into the body of water 1602. In the illustrated
embodiment, the body of water is an open body of water, such as a
lake or pond. Alternatively, the body of water 1602 may be an
underground body of water, including a reservoir, an underground
lake, an underground river, etc. Although shown as a horizontal
array of tubes, secondary heat exchanger 1600 may be a vertical
array of tubes, a horizontal array of tubes, an array of coils, an
array of vertical and horizontal tubes, an array of arbitrary
angled tubes, and/or any suitable combination of horizontal tubes,
vertical tubes, arbitrary angled tubes, and coils.
[0080] FIG. 17 is a simplified diagram of another temperature
regulation system 400 including heat exchanger 300 coupled to PV
module 100 and a secondary heat exchanger 1700. The cooling fluid
flows through heat exchanger 300 in a first fluid loop. The
secondary heat exchanger 1700 is configured to transfer at least
some of the heat contained in fluid exiting the heat exchanger 300
to a secondary fluid loop. In the illustrated embodiment, the
secondary fluid loop provides heated water for residential,
commercial, industrial, or any other suitable application. More
particularly, the secondary heat exchanger 1700 receives the heated
fluid from the heat exchanger 300 and cooler water from a water
supply (not shown). A second pump 1702 pumps the water to secondary
heat exchanger 1700. The heat contained in the fluid exiting the
heat exchanger 300 is transferred to the water pumped into the
secondary heat exchanger 1700. The reduced temperature cooling
fluid is returned to the heat exchanger 300 by pump 404. The heated
water exits the secondary heat exchanger 1700 and is delivered for
use.
[0081] FIG. 18 is a simplified diagram of another temperature
regulation system 400 including heat exchanger 300 coupled to PV
module 100 and a secondary heat exchanger 1800. The cooling fluid
flows through heat exchanger 300 in a first fluid loop. The
secondary heat exchanger 1800 is configured to transfer at least
some of the heat contained in fluid exiting the heat exchanger 300
to a secondary fluid loop. In the illustrated embodiment, the
secondary fluid loop provides heated air for residential,
commercial, industrial, or any other suitable application. More
particularly, the secondary heat exchanger 1800 receives the heated
fluid from the heat exchanger 300 and a cooler air input. A pump,
fan, blower, or other suitable motivator (not shown) forces the
cooler air into secondary heat exchanger 1800. The heat contained
in the fluid exiting the heat exchanger 300 is transferred to the
air in secondary heat exchanger 1800. The reduced temperature
cooling fluid is returned to the heat exchanger 300 by pump 404.
The heated air exits the secondary heat exchanger 1700 and is input
to an auxiliary heater 1802 to provide additional heat to the air.
Alternatively, the heated air exiting the secondary heat exchanger
1800 is delivered for use without heating by an auxiliary heater
1802.
[0082] FIG. 19 is a simplified diagram of another temperature
regulation system 400 including heat exchanger 300 coupled to PV
module 100 and a secondary heat exchanger 1900. The cooling fluid
flows through heat exchanger 300 in a first fluid loop. The
secondary heat exchanger 1900 is a phase change material (PCM)
combined heat storage and heat exchanger configured to transfer at
least some of the heat contained in fluid exiting the heat
exchanger 300 to a secondary fluid loop. In the illustrated
embodiment, the secondary fluid loop provides heated water for
residential, commercial, industrial, or any other suitable
application. More particularly, the secondary heat exchanger 1900
receives the heated fluid from the heat exchanger 300 and cooler
water from a water supply (not shown). A second pump 1902 pumps the
water to secondary heat exchanger 1900. The heat contained in the
fluid exiting the heat exchanger 300 is transferred, via a phase
change material, to the water pumped into the secondary heat
exchanger 1900. The reduced temperature cooling fluid is returned
to the heat exchanger 300 by pump 404. The heated water exits the
secondary heat exchanger 1900 and is delivered for processing
and/or use.
[0083] FIG. 20 is a simplified diagram of another temperature
regulation system 400 including heat exchanger 300 coupled to PV
module 100 and a secondary heat exchanger 2000. The cooling fluid
flows through heat exchanger 300 in a first fluid loop. The
secondary heat exchanger 2000 is configured to transfer at least
some of the heat contained in fluid exiting the heat exchanger 300
to a secondary fluid loop. In the illustrated embodiment, the
secondary fluid loop provides heated water for residential,
commercial, industrial, or any other suitable application. More
particularly, the secondary heat exchanger 2000 receives the heated
fluid from the heat exchanger 300 and cooler water from a water
supply (not shown). A second pump 2002 pumps the water to secondary
heat exchanger 2000. The heat contained in the fluid exiting the
heat exchanger 300 is transferred to the water pumped into the
secondary heat exchanger 2000. The reduced temperature cooling
fluid is returned to the heat exchanger 300 by pump 404. The heated
water exits the secondary heat exchanger 2000 and is delivered to
an insulated hot water storage tank 2004. The storage tank 2004
includes an auxiliary heater 2006 to provide additional heat to the
water stored in the storage tank 2004. Alternatively, the auxiliary
heater 2006 may be omitted. The heated water stored in storage tank
2004 is delivered from the hot water storage tank 2004 for
processing and/or use. In the illustrated embodiment, pump 2002
pumps water from storage tank 2004 to secondary heat exchanger
2000, while the water supply provide water into storage tank 2004
as needed. Alternatively, water may be provided to secondary heat
exchanger 2000 from the water supply directly.
[0084] FIG. 21 is a simplified diagram of another temperature
regulation system 400 including heat exchanger 300 coupled to PV
module 100 and a secondary heat exchanger 2100. The secondary heat
exchanger 2100 is an array of coils 2102 for underfloor heating or
in-wall heating. The coils 2102 are disposed underneath the surface
of a floor and/or within the walls (not shown) in a home, office,
warehouse, etc. In some embodiments, the coils 2102 are disposed
within a floor, such as by being embedded in a concrete foundation.
The secondary heat exchanger 2100 may be made of metal, plastic, or
any other suitable material or combination of materials. The heated
fluid exiting the heat exchanger 300 flows through the secondary
heat exchanger 2100 before being returned by pump 404 to the heat
exchanger 300. At least some of the heat stored in the fluid is
dissipated through the secondary heat exchange 2100 into the floor
and/or through the walls. Secondary heat exchanger 2100 may be
include a vertical array of tubes, a horizontal array of tubes, an
array of coils, an array of vertical and horizontal tubes, an array
of arbitrary angled tubes, and/or any suitable combination of
horizontal tubes, vertical tubes, arbitrary angled tubes, and
coils.
[0085] FIG. 22 is a simplified diagram of another temperature
regulation system 400 including heat exchanger 300 coupled to PV
module 100 and a secondary heat exchanger 2200. The cooling fluid
flows through heat exchanger 300 in a first fluid loop. The
secondary heat exchanger 2200 is configured to transfer at least
some of the heat contained in fluid exiting the heat exchanger 300
to a secondary fluid loop. The secondary fluid loop provides heated
water for heating a body of water. In the illustrated embodiment,
the body of water is a pool 2202. Alternatively, the body of water
may be a pond, a lake, a tub, or any other body of water that may
benefit from heating. The secondary heat exchanger 2200 receives
the heated fluid from the heat exchanger 300 and cooler water from
the pool 2202. A second pump 2204 pumps the water to secondary heat
exchanger 2200. The heat contained in the fluid exiting the heat
exchanger 300 is transferred to the water pumped into the secondary
heat exchanger 2200. The reduced temperature cooling fluid is
returned to the heat exchanger 300 by pump 404. The heated water
exits the secondary heat exchanger 2200 and is delivered to the
pool 2202.
[0086] PV modules 100 including heat exchangers 300 may be mounted
to any suitable support structure. For example, a PV module 100
with heat exchanger 300 may be mounted to a ground based rack, a
roof (whether directly or via a rack), a solar tracker, etc.
[0087] FIG. 29 is a side elevation view of a system 2900 including
PV module 100 and heat exchanger 300 (not visible) mounted to a
solar tracker 2902. Tracker 2902 is a horizontal single axis
tracker configured to rotate the PV module 100 about an axis of
rotation (going into the page) at point 2904. Alternatively, the
tracker 2902 may be a multi-axis tracker, a single axis tracker
rotating about a different axis of rotation, or any other suitable
solar tracker. Moreover, although a single PV module 100 is shown
in FIG. 29, system 2900 may include more than one PV module
100.
[0088] Solar trackers (sometimes referred to herein as trackers or
tracking devices) are used to alter the position of one or more PV
modules 100 mounted to the tracker to attempt to control an angle
of incidence 2906 of sunlight on the PV modules. Typically, the
desired angle of incidence 2906 is normal (i.e. ninety degrees) to
the PV module 100. This substantially maximizes the solar energy
that is received by the PV modules 100 throughout the day. The
increased light intensity on the PV module increases the output
current of the PV module 100, thereby leading to increased power
output. The introduction of trackers can boost the output power of
a solar power plant by, for example, 10%-35%. The increased light
intensity on the PV module 100 also increases the temperature of
the PV module 100. PV modules 100 mounted on solar trackers will
often be 10.degree. C.-15.degree. C. hotter than a similar module
100 mounted in a fixed position. Heat exchanger 300 reduces the
temperature of the PV module 100 and offsets at least a portion of
the increased temperature of the PV module 100.
[0089] FIGS. 30A-30D compare the characteristics of an uncooled PV
module 100 (i.e., without a heat exchanger 300) and a cooled PV
module 100 (i.e., with a heat exchanger 300) for various angles of
incidence of light on the PV module. In this example, the light was
generated using a lamp and the indicated angle of incidence is
relative to normal. Thus, at an angle of 0 degrees, the PV module
100 faces the lamp directly and receives the most incident light
from the lamp. FIG. 30A presents the output power of the modules
100 as a function of the angle of incidence. FIGS. 30B and 30C show
the short circuit current and the open circuit voltage,
respectively, of the PV modules 100. The temperature of the PV
modules 100 is shown as a function of the angle of incidence in
FIG. 30D. As can be seen, the cooled module remained significantly
cooler than the uncooled module. The cooled module 100 provided
higher open circuit voltages at substantially the same short
circuit current as the uncooled module 100, thereby generating more
output power.
[0090] As mentioned above, PV modules 100 may be mounted to a roof
of a building. As is well known, a significant amount of heat
enters a building through the roof from sunlight shining on the
roof. Placing PV modules on a roof shades the portion of the roof
under the PV module from the sun, thereby reducing the temperature
of the roof and potentially reducing the amount of heat entering
the building through the roof. FIG. 31 is a diagram of a PV module
100 mounted to a roof 3100 of a building 3102. In FIG. 31, PV
module 100 is mounted such that it is spaced a distance d from the
surface of roof 3100. The distance d is selected to provide
clearance to permit air (e.g., wind) to pass between the roof 3100
and the PV module 100 to facilitate cooling the PV module 100.
Reducing the distance d reduces the wind loading that the PV module
100 applies to the roof 3100, at the cost of reduced cooling of the
PV module (because less air can flow between the PV module 100 and
the roof 3100). When the PV module 100 is flush mounted on roof
3100, as shown in FIG. 32, the distance d is reduced substantially
to zero and the PV module's contribution to wind loading of the
roof 3100 is substantially minimized. However, the cooling produced
by air passing between the PV module 100 and the roof 3100 is
nearly eliminated. Use of heat exchanger 300 with roof mounted PV
modules reduces the temperature of the module 100 without reliance
on the airflow between the PV module 100 and the roof 3100.
[0091] FIG. 33 presents temperature measurements obtained for
installation with various distances d (referred to in FIG. 33 as
"Height") for an uncooled PV module 100 and a cooled PV module 100
(i.e., PV module 100 with heat exchanger 300). As can be seen, the
temperature of the PV module 100 (whether cooled or uncooled)
increased as the distance d decreased. The cooled module 100,
however, was significantly cooler than the uncooled module 100 at
all heights and had a smaller temperature change than the uncooled
module 100 as the distance d changed. Moreover, when distance d was
reduced to zero (i.e., the modules 100 were flush mounted), the
temperature of the cooled module 100 was still less than the
temperature of the uncooled module at any distance. Similarly, the
temperature of the roof under the PV modules 100 increased as the
distance d decreased. The roof temperature under the cooled PV
module 100 remained cooler than the roof under the uncooled PV
module 100 at all distances d. Thus, a cooled PV module 100 (i.e.,
including heat exchanger 300) may be installed spaced apart from
the roof 3100, flush with the roof 3100, or anywhere in between to
achieve a desired wind loading on the roof 3100, reduction in roof
temperature, and/or aesthetic appearance of the installed
system.
[0092] Moreover, as shown in FIG. 34, a roof mounted PV module 100
and heat exchanger 300 may be used as part of any of the example
temperature regulation systems 400 described above. The cooling
fluid passed through the heat exchanger may be used for additional
purposes as described above (for example with respect to FIGS.
17-22). Thus, a temperature regulation system 400 may include roof
mounted PV modules 100 that reduce the temperature of the roof,
thereby reducing the temperature in the building and reducing the
cost to cool the building. The system 400 also provides hot water
(or other thermal transfer fluid) that may be used to heat drinking
water, heat non-potable water, heat an environment, etc., thereby
further reducing electrical usage (and costs) for the building.
[0093] Additionally, a roof mounted PV module 100, may be recess
mounted into the roof. The amount of recess into the roof may be
varied to vary the distance between the top surface 106 of the PV
module 100 and the surface of the roof. In some embodiments, the PV
module may be recessed to position the top surface 106 of the PV
module 100 level or below the surface of the roof. Recessing the PV
module 100 into the roof reduces the wind loading on the PV module
100 (and thereby reduces the wind loading on the roof). The reduced
wind loading may permit fewer structural components to be used to
mount the PV module 100 to the roof, thereby reducing costs.
[0094] It should be recognized that the temperature regulation
systems described above may be combined without departing from the
scope of this disclosure. For example, a temperature regulation
system may include the secondary heat exchanger 1700 and the
secondary heat exchanger 1400. Cooling fluid exiting the secondary
heat exchanger 1700 may be delivered to secondary heat exchanger
1400 for further heat dissipation. Moreover, the systems described
herein are not limited to the uses described above. For example,
systems of this disclosure may be used to provide a low grade
energy input to vapor absorption systems for cooling applications.
Other uses include a wide range of heating applications in the food
product industry, dairies, breweries, distilleries, automobile
industry, machine industry, chemical industries, paper and pulp
industries, timber processing, etc.
[0095] Although the exemplary embodiments were described above with
reference to a single device 402 and/or a single PV module 100, the
apparatus, methods, and systems described herein are not so
limited. A temperature regulation system 400 may include more than
one heat exchanger 300 coupled to one or more devices 402. FIGS. 23
and 24 illustrate two exemplary configurations of such systems. In
FIG. 23, the system 400 includes four heat exchangers 300. PV
modules 100 are coupled to each heat exchanger 300. The fluid flows
through the heat exchangers 300 in parallel. Cooling fluid branches
off from an input 2300, e.g. the output of pump 404, to provide
cooling fluid to each heat exchanger 300. The cooling fluid exiting
each heat exchanger 300 is provided to an output 2302 to be
delivered to a secondary heat exchanger. In FIG. 24, the cooling
fluid flows through four heat exchangers 300 in series. The cooling
fluid output from one heat exchanger 300 is input to the next heat
exchanger 300 in the series. The cooling fluid from the last heat
exchanger in the series or delivered to a secondary heat exchanger
for extraction of the heat in the cooling fluid. The parallel
configuration shown in FIG. 23 provides for a greater cooling fluid
flow rate than the series configuration shown in FIG. 24. The
series configuration of FIG. 24 provides a higher output
temperature for the cooling fluid than the parallel configuration
shown in FIG. 23. Moreover, the parallel configuration of FIG. 23
may provide more even cooling of the PV modules 100 than the series
connection of FIG. 24.
[0096] The heat exchangers and systems described herein generally
provide inexpensive and effective ways to regulate temperature of a
device, such as a PV module. Moreover, the temperature regulation
provided by the exemplary heat exchangers and systems may permit PV
modules to be mounted without the significant gap typically needed
between the back of the PV module and an underlying support (such
as a roof) to permit natural convective cooling of the PV module.
Such flush mounting of PV modules may decrease wind loading on
support structures and reduce installation costs. Moreover,
experiments have shown that the temperature of the surface beneath
PV modules including the exemplary temperature regulation systems
may be lower than the surface beneath a PV module without the
exemplary temperature regulation systems. This can reduce
conductive and/or convective heating of space below the mounting
surface. In roof mounted installations, the space beneath the
mounting surface may be the interior of a building. Accordingly,
the exemplary systems may facilitate reducing the cooling costs of
a building to which PV modules are attached.
[0097] Some embodiments of the heat exchangers disclosed herein can
be integrated into the backsheet structure of a PV module using
only an encapsulant and can thereby capitalize on existing
manufacturing infrastructure and corresponding economy of scale.
Some embodiments of the heat exchangers can be used with a simple
attachment mechanism to be affixed to nearly any PV modules,
thereby making it field-retrofittable and easy to clean and/or
replace. These heat exchangers are thus usable to convert a
conventional PV system or module into a PV-thermal system.
[0098] Moreover, coolant losses in the exemplary heat exchangers
and systems will be negligible in a properly constructed system
because coolant is retained within the system, i.e., it is a closed
loop system, and there is no provision to allow coolant to
intentionally escape. When used to cool PV modules, some heat
exchangers of this disclosure have produced a decrease in PV module
temperature of 18-20.degree. C., and increased power output of the
PV modules by about 10% at peak operating conditions. Other
implementations may result in greater or lesser temperature
reductions and/or greater or lesser increases in PV module
efficiency. Furthermore, some embodiments provide useful
dissipation of the heat extracted from a device. For example, the
extracted heat may be used to provide heated water, to heat a pool
or other body of water or liquid, and/or to heat air.
[0099] When introducing elements of the present invention or the
embodiment(s) thereof, the articles "a", "an", "the" and "said" are
intended to mean that there are one or more of the elements. The
terms "comprising", "including" and "having" are intended to be
inclusive and mean that there may be additional elements other than
the listed elements.
[0100] As various changes could be made in the above without
departing from the scope of the invention, it is intended that all
matter contained in the above description and shown in the
accompanying drawings shall be interpreted as illustrative and not
in a limiting sense.
* * * * *