U.S. patent application number 13/579511 was filed with the patent office on 2013-01-31 for prefabricated insulated thermal energy storage enclosure.
The applicant listed for this patent is Daniel Callaghan. Invention is credited to Daniel Callaghan.
Application Number | 20130025817 13/579511 |
Document ID | / |
Family ID | 44562757 |
Filed Date | 2013-01-31 |
United States Patent
Application |
20130025817 |
Kind Code |
A1 |
Callaghan; Daniel |
January 31, 2013 |
PREFABRICATED INSULATED THERMAL ENERGY STORAGE ENCLOSURE
Abstract
A thermally insulated enclosure manufactured in pre-assembled or
kit form, and constructed of prefabricated insulated sandwich
panels, or structural insulated sandwich panels in some
embodiments, rated for relatively high operating temperatures and
designed for the storage of thermal energy in solid phase
particulate storage medium or media at up to 125 deg C. and
possibly higher. Said energy storage medium or media will typically
be sand, gravel, or other powder or granulated material, or
combination thereof, and optionally some proportion of phase change
material. Said insulated enclosure is designed to accommodate a
variety of heat transfer device designs in storing solar energy and
off-peak-generated electric energy. The primary applications for
the invention are expected to be in domestic hot water heating,
space heating, and process heating, however in addition the thermal
energy retained in the enclosure can also be used in powering the
refrigeration cycle in some space cooling systems.
Inventors: |
Callaghan; Daniel;
(Brooklyn, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Callaghan; Daniel |
Brooklyn |
|
CA |
|
|
Family ID: |
44562757 |
Appl. No.: |
13/579511 |
Filed: |
March 12, 2010 |
PCT Filed: |
March 12, 2010 |
PCT NO: |
PCT/CA10/00327 |
371 Date: |
October 16, 2012 |
Current U.S.
Class: |
165/10 |
Current CPC
Class: |
F28D 20/021 20130101;
Y02E 70/30 20130101; F28F 2270/00 20130101; Y02B 10/20 20130101;
F24S 10/80 20180501; Y02E 10/44 20130101; F28D 20/0056 20130101;
Y02E 60/14 20130101; F24S 60/10 20180501 |
Class at
Publication: |
165/10 |
International
Class: |
F28D 17/00 20060101
F28D017/00 |
Claims
1. A prefabricated enclosure for storing thermal energy from an
external energy source of solar radiation or electricity, or a
combination of the two, with said storage to be in a particulate
solid phase thermal energy storage medium or media (PTESM) (18,
19), with said enclosure comprising prefabricated insulated panel
assemblies for the floor, walls and roof, with said assemblies
fabricated as structural insulated sandwich panels with rigid
facings (1, 3) and insulative core (2), with said facings and core
being layers of said panel assemblies and bonded together at their
contact surfaces and designed to act compositely in resisting the
gravity and lateral loading imposed by the aforementioned PTESM
over its anticipated operating temperature range, or alternately
with said insulative core being a foamed-in-place grade of
insulation such as is possible with polyurethane foam and such that
said foam self-adheres to said facings with the required adhesive
strength, and with the four edges of said panel assemblies prepared
in a manner to minimize thermal bridging through such edge
connections (11, 12, 11a 12a), and with panel corner edge brackets
and attendant fasteners (8, 9) being of the necessary structural
strength to connect said insulated sandwich panels to each other in
a manner that maintains the structural integrity of said enclosure
under all anticipated loadings, and with said enclosure suitable
for the installation in its interior of one or more thermal energy
input transfer device(s) to transfer thermal energy from said
external source to said PTESM and one or more thermal energy output
transfer device(s) being in the form of coil(s) of piping design
(14), with or without heat transfer fins to transfer thermal energy
from said PTESM either directly or indirectly to the "end use"
application of said stored energy, with said end use being for one
or a combination of domestic hot water heating, space heating,
swimming pool or similar use heating, or in powering the
refrigeration cycle by means of thermally-driven coolers in space
cooling systems.
2. A prefabricated enclosure for storing thermal energy as in claim
1 with said insulative core of said sandwich panels to consist of
multiple bonded layers of different insulative materials such that
adequate structural and thermal performance is provided by the core
in achieving the required structural performance of said sandwich
panels as a whole thereby permitting less costly materials to be
used where maximum temperature resistance requirements through the
thickness of said insulative core is reduced as a result of the
temperature gradient that naturally occurs through said sandwich
panel assemblies with increasing distance from the aforementioned
and heated said PTESM
3. A prefabricated enclosure for storing thermal energy as in claim
1, with solar radiation being the sole aforementioned external
energy source and with the aforementioned thermal energy transfer
devices provided with the enclosure, and the thermal energy input
transfer device(s) being in the form of coil(s) of piping design
(14), with or without heat transfer fins, and with input piping to
said device(s) being suitable for attachment to the outlet piping
from external solar collectors that form part of the energy
collection system of said solar energy source.
4. A prefabricated enclosure for storing thermal energy as in claim
1, with electrical energy being the sole aforementioned external
energy source and with the aforementioned thermal energy transfer
devices provided with the enclosure, and the thermal energy input
transfer device(s) being in the form of electrical resistance
wiring.
5. A prefabricated enclosure for storing thermal energy as in claim
1, with solar radiation and electrical energy being the
aforementioned external energy sources with the aforementioned
thermal energy transfer devices provided with the enclosure, and
the thermal energy input transfer device(s) being in the form of
coil(s) of piping design (14), with or without heat transfer fins
and also in the form of electrical resistance wiring, such that the
aforementioned PTESM can be heated by a combination of external
energy sources of solar radiation and electrical energy.
6. A prefabricated enclosure for storing thermal energy as in claim
1, and with the aforementioned thermal energy transfer devices
provided with the enclosure, and the thermal energy input transfer
device(s) being in the form of hot air ducting.
7. A prefabricated enclosure for storing thermal energy as in claim
2 with the aforementioned prefabricated structural sandwich panel
assemblies all provided with insulative sleeves (16) at the
locations where the aforementioned piping, wiring, and ducting of
the associated aforementioned thermal energy transfer device(s)
penetrate said sandwich panels.
8. A thermal energy storage enclosure as in claim 1 with the
aforementioned prefabricated structural sandwich panel assemblies,
panel assembly corner edge brackets, and fasteners, and some or all
of the aforementioned internal heat transfer devices with
aforementioned associated insulative sleeves all provided in kit
form ready for assembly.
9. A thermal energy storage enclosure as in claim 1, but where the
aforementioned sandwich wall panel assemblies are not required to
act compositely in resisting flexural or shearing stresses
resulting from the lateral loading imposed by the aforementioned
PTESM over the anticipated temperature range of said PTESM, but
rather are braced against external framing (13a) that provides
those strength requirements.
10. A thermal energy storage enclosure as in claim 1, but where the
aforementioned sandwich floor panels are not required to act
compositely in resisting applied flexural or shearing stresses
resulting from the gravity loading imposed by the aforementioned
PTESM over the anticipated temperature range of said storage medium
but rather are braced against external framing (26) or other
structural floor construction as in a structural concrete slab that
provides those strength requirements.
11. A thermal energy storage enclosure as in claim 1, with the
aforementioned PTESM being sand or other relatively fine
particulate-sized granular matter with the option of achieving
increased energy storage capacity provided by some fraction of the
volume of said PTESM being displaced by a phase change
material.
12. A thermal energy storage enclosure as in claim 1, with the
aforementioned PTESM being gravel or other graded and relatively
coarser particulate-sized material with the option of achieving
increased energy storage capacity provided by some fraction of the
volume of said PTESM being displaced by a phase change
material.
13. A thermal energy storage enclosure as in claim 1, with the
aforementioned PTESM being both sand and gravel or aforementioned
alternatives with the two grades of said PTESM being separated from
each other by one or more metallic cylindrical fabrication(s)
extending between the interior facings of the aforementioned floor
and roof sandwich panels of said enclosure with the main heat
transfer portions in coil form of the aforementioned heat transfer
devices installed inside said cylindrical fabrication(s) and said
sand grade or said alternative of said PTESM being placed inside
said cylindrical fabrication(s) thereby reducing the possibility of
damage to said main portions of heat transfer devices during the
filling process of said PTESM, and said gravel grade or said
alternative of said PTESM being placed outside said cylindrical
fabrication(s) with said separation of grades of PTESM thereby
allowing the selective removal of said sand grade or said
alternative of said PTESM thereby facilitating access to and
possible removal of any said heat transfer devices installed within
said fabrication(s) for service and/or replacement and said
separation of grades of PTESM also yielding benefits from improved
thermal energy storage characteristics of said gravel grade or said
alternative of PTESM relative to said sand grade or said
alternative of PTESM yet also yielding the benefits of selected use
of the sand grade or said alternative PTESM as heretofore
described.
14. A thermal energy storage enclosure as in claim 13 with some
fraction of one or both of the aforementioned grades of PTESM being
displaced by a phase change material as a means of achieving
increased thermal energy storage capacity.
15. A thermal energy storage enclosure as in claim 1 in which
provisions are made in the structural design of said enclosure to
allow the temporary removal of specific aforementioned
prefabricated sandwich roof panel assembly(ies) while maintaining
the structural integrity of the overall enclosure structure either
through the addition of temporary structural reinforcing elements
or the installation of permanent reinforcing elements to adjacent
panel assemblies, or a combination of these two methods, with said
provisions being made to facilitate the selective removal by means
of vacuum or other process the portion of the aforementioned PTESM
residing within the aforementioned metallic cylindrical
fabrication(s) and encasing the aforementioned heat transfer
devices, thereby facilitating access to and possible removal of
said heat transfer devices installed within said cylindrical
fabrication(s) for service and/or replacement of said heat transfer
devices without necessitating the removal of the remainder of said
PTESM.
16. A thermal energy storage enclosure as in claim 1 with a network
of prefabricated conduit to accommodate wiring and temperature
sensor devices, with said conduit propitiously positioned within
the interior space of said enclosure or provided in kit form for
installation during the assembly process of said enclosure, thereby
allowing said sensor devices to be securely installed at
predetermined locations in the aforementioned PTESM for the purpose
of providing data to a process control system that manages the heat
transfer processes involved.
17. Thermal energy storage enclosure as in claim 1 wherein
additional sandwich panel layered components, comprising a high
temperature insulative layer (5) and high temperature protective
liner panel (6), with the latter being in intimate contact with the
aforementioned PTESM, are bonded to the aforementioned
prefabricated insulated sandwich panel assemblies of the walls,
floor and roof of said enclosure to provide added protection
against deterioration in the structural and/or thermal performance
of said sandwich panel assemblies and hence similar deterioration
in the structural and/or thermal performance of said enclosure as a
whole assembly, due to upper temperature extremes reached in the
aforementioned PTESM that would otherwise cause a reduction in the
strength and/or insulative properties of the structural layers and
adhesive comprising said insulated sandwich panel assemblies.
18. Thermal energy storage enclosure as in claim 1 whereby said
enclosure is installed in an exterior setting and wherein the
design and specifications, or actual materials for roof framing
(22) and weatherproofing components for the roof and for the walls
of said enclosure are provided, with said weatherproofing
components comprising conventional roof and wall sheathing (22, 23)
and conventional roof coverings, resulting in a conventional
"outbuilding" appearance, but with said energy storage enclosure
forming the underlying structural form in resisting the additional
imposed design loadings of an environmental nature, including wind,
snow and seismic loading, and with additional aesthetic
requirements met by tailoring the shape of the visible said
outbuilding structure, and incorporating trim elements, including
facade-style window (24) and door (25) elements in providing an
appearance that is complementary to the site and adjoining
buildings.
19. Thermal energy storage enclosure in an exterior setting as in
claim 18 wherein the aforementioned sandwich wall panel assemblies
of said enclosure are not required to act compositely in resisting
applied compression forces in the axis of the facing panels, or
flexural or shearing stresses resulting from the lateral loading
imposed by both the aforementioned PTESM over the anticipated
temperature range of said PTESM and from aforementioned design
loadings of an environmental nature, but rather whereby said
sandwich wall panel assemblies are braced against external framing
(13a) that provides those strength requirements, with said external
framing also serving as the base structural form for attachment of
aforementioned wall sheathing and roof framing as required for the
aforementioned outbuilding construction.
20. Thermal energy storage enclosure in an exterior setting as in
claim 18 wherein the external energy source is solar, and the roof
of the aforementioned enclosure outbuilding is used as a base
structural form for mounting associated solar collectors (27), and
furthermore, as a means of increasing space for said collectors,
the roof structure in said outbuilding can be made asymmetrical to
preferentially increase space available to said solar collectors.
Description
TECHNICAL FIELD
[0001] This disclosure relates generally to enclosures for the
storage of thermal energy, and more specifically to such enclosures
utilizing solid phase storage medium or media as opposed to a
liquid phase storage medium. Said enclosures are constructed of
prefabricated insulated sandwich panel assemblies forming the
walls, floor and roof sections, suitable for manufacture as
pre-assembled units and/or in kit form, with varying options in
terms of ancillary components, such as internal heat transfer coils
as described herein.
BACKGROUND ART
[0002] It is generally known that storage of thermal energy for
later release and transfer to a structure, process or other entity
requiring heat can be a useful and cost efficient undertaking. This
concept is often used, for example, in active solar heating
systems, commonly in residential, institutional, and commercial
installations for domestic water heating or space heating. Other
examples are process systems requiring thermal energy in commercial
and industrial settings, and in heating water in swimming pools and
similar facilities.
[0003] The benefits of such systems are in a reduction in the
consumption of traditional non-renewable energy resources such as
fossil fuels, in direct energy cost savings, or as an aid in
enabling the deferral of construction of new capital-intensive
electric generating facilities through the increased use of
off-peak generation, an advantage that also benefits the consumer
in the form of lower power rates.
[0004] It is commonly accepted that the need for more efficient use
of renewable energy sources, such as solar power, and better
utilization of non-renewable energy resources, as in off-peak
electrical generation, will continue to grow as traditional fossil
fuel resources are further depleted.
[0005] Storage of thermal energy for later release, as described
above, is often achieved through the use of storage tanks
containing a medium of water, brine, or other liquids, or in a
storage medium of earth, rocks or other solid materials, all
provided with some means of transferring said energy into, and
recovery from, the energy storage medium. In some cases phase
change materials (PCMs) are used to take advantage of the latent
heat of fusion capacity available in such materials.
[0006] A number of previous patents have been issued for
apparatuses that focus on the storage of thermal energy, however
there are distinct and significant differences in the processes and
apparatuses described in those patents in accomplishing this
objective from those of the current invention, as summarized
hereinafter.
[0007] Firstly, those patents generally identify solar as the sole
energy source of interest, as opposed to one or both of solar and
electrical as per the current invention.
[0008] Some previous patents, namely Can. 1,040,953 (Atkinson,
issued Oct. 24, 1978) and Can. 1,020,828 (Strickland et al, issued
Nov. 15, 1977) provide for thermal energy storage in an enclosure,
both utilizing rocks as the storage medium, but also focus on the
novelty of the means of the actual collection of said energy. The
apparatuses defined by said patents are not particularly
well-suited to the utilization of state-of-the-art but conventional
solar collectors, for instance, as the means of energy collection.
Also, retrieval of the stored thermal energy is by air circulation,
which has practical limitations in many applications. In addition,
and of significance with respect to the current invention, the ease
and practicality of construction of said enclosures are not prime
considerations in these patents, as with the current invention.
[0009] Other existing patents, namely Can. 1,108,879 (Balch, issued
Sep. 15, 1981), and Can. 1,082,545 (Yaun, issued Jul. 29, 1980) are
for systems and apparatuses in which the energy storage is achieved
through utilization of ground mass in buried systems. These
typically rely on relatively complex processes and apparatuses in
storing and retrieving the thermal energy. By their nature they are
typically intended for larger scale energy storage than that
generally intended with the current invention.
[0010] Still other previous patents, namely Can. 1,206,106 (Hofius
and Moses, issued Jun. 17, 1986), and Can. 1,160,923 (Stice, issued
Jan. 24, 1984), focus primarily on the containers for retention of
a thermal energy storage medium, and manufacturing of the same.
Said patents offer distinctly different approaches to thermal
energy storage requiring more highly specialized processes in the
manufacturing of the inventive containers in comparison to those
required with the current invention, and also are tailored to the
use of PCMs as the primary energy storage media. As noted
heretofore, PCMs do have one advantage over the particulate solid
materials proposed herein, but they also typically have some
disadvantages, including relatively high costs and the potentially
problematic trait of experiencing relatively significant magnitudes
of expansion and contraction in passing through the phase change
temperature, a trait that must be physically accommodated in the
apparatuses of the energy storage method employed. The inventive
containers of the aforementioned patents that hold the PCMs also
collect the solar energy directly, and are not particularly
well-suited to the utilization of high efficiency conventional
solar collectors, or off-peak electrical generation as sources for
said energy, as proposed in the current invention.
[0011] The most common method of providing thermal energy storage
in active solar systems in residential, commercial, institutional,
and industrial settings, has been through single or multiple
storage tanks containing water as the energy storage medium.
Although water is known to have higher specific and volumetric heat
capacities than most solid phase materials, and can thus store
greater quantities of heat per given mass and volume respectively,
concerns related to the risks of storing relatively large
quantities of water can, for a variety of reasons, effectively
impose fixed capacity limits on thermal storage systems using that
medium.
[0012] Concerns over leakage of the contained liquid in these
storage tanks typically increase with increasing storage volume,
and also with increasing operating temperatures due to safety
considerations of potential human contact exposure. If additional
thermal energy storage is desired beyond that achievable at a given
operating pressure, it is necessary to increase said pressure of
the storage tank or tanks, thereby further increasing safety
concerns related to the accidental release of steam. Furthermore,
storage of thermal energy in water storage tanks with the water
retained for some time within a relatively moderate temperature
range of between 20.degree. and 50.degree. C.
(68.degree.-122.degree. F.) can lead to the spread of
microorganisms responsible for legionnaire's disease, (ref. OSHA
Technical Manual, Section 3, Chapter 7, Legionnaire's
Disease--updated effective Jun. 24, 2008) resulting in increased
risk to individuals exposed to said water.
[0013] Thermal storage capacity limitations of water tanks as
discussed above can impose restrictions on the capabilities of
potential installations, such as in restricting residential and
institutional solar heating systems to the supply of domestic hot
water (DHW) alone, rather than being supportive to the design of
said systems to also provide supplemental thermal energy for space
heating.
[0014] Where some form of solid phase thermal storage medium is
used, rather than liquid phase, enclosures have not been available
in an economical prefabricated form that facilitates construction
and satisfies economic viability requirements to the extent being
proposed in the current invention. Because of the relatively high
temperatures that can be attained in thermal storage systems in
some energy collection processes, specialized knowledge of material
characteristics and specific design and construction details
appropriate for a suitable enclosure are required. Such specialized
knowledge requirements can thereby constrain potential constructors
not trained in the art, resulting in the need for specialists in
the field, and potentially leading to higher costs than can be
justified in many situations. Alternately, defective designs and
unsatisfactory performance can also result.
[0015] Accordingly there is a need in the art for a pre-engineered
prefabricated enclosure, for use with solid phase thermal energy
storage media that is economical, of adequate strength, highly
thermally insulated, able to withstand the exposure temperatures to
which it is subjected, and with the required thermal storage
capacity and means of heat transfer, such as appropriately
configured heat transfer coils of electrical wiring or piping
design, with all components in a form that can be readily assembled
by persons without specialized knowledge of the process and
material characteristics required in the construction of said
enclosure and ancillaries. Said heat transfer coils should be in a
form suitable for connection to standard state of the art energy
recovery systems, such as solar-based or electric, with the latter
typically being in conjunction with an off-peak generation purchase
agreement.
[0016] The enclosure should be of a design that can be varied in
size to cover a range of thermal energy storage capacities and
applications. The enclosure should be adaptable to either interior
or exterior installations, with the latter being in a form suitable
for mounting of solar collectors on the roof of said enclosure if
advantageous in a solar-based system, and also one that satisfies
the aesthetic requirements of the installation. This latter
consideration, namely aesthetics, can be significant in
establishing an embodiment of the thermal energy storage enclosure
as the preferred alternative in an outside setting to other
energy-saving and/or cost-saving options that may be available, but
that may not offer as great an economic advantage through reduced
energy costs.
DISCLOSURE OF INVENTION
[0017] The present invention is a prefabricated insulated enclosure
for the storage of thermal energy in solid phase particulate
storage medium or media (PTESM) at temperatures up to 125 deg C.
and possibly higher, that provides a practical alternative to a
single or multiple water storage tank(s) typically used for this
application, such as in solar-heated DHW and space heating
installations, and also as an alternative to other methods and
enclosures that utilize a solid phase storage medium, but that lack
the innovations and advantages featured in the current invention.
The PTESM used to fill the enclosure can be sand, gravel, or other
powder or granulated material, or, as described later in this
section, a combination of particulate media grades, with the
different grades separated by a cylindrical metallic structural
partition, thereby benefiting the heat transfer processes involved
due to specific properties characteristic of each grade as
discussed hereinafter. In addition, it is also possible to
incorporate PCMs as a portion of the PTESM used, thereby benefiting
from latent heat capacity of the PCMs in addition to the sensible
heat capacity of the PTESM. The inventive enclosure is adaptable to
both interior installations, and exterior installations with
appropriate weather protection elements added to the enclosure as
further described hereinafter.
[0018] The inventive enclosure is constructed of a set of
panel-type envelope components forming the two side walls, two end
walls, roof and floor. Said envelope panel components are designed
as prefabricated composite "sandwich" type assemblies with rigid
facing panels and a core of sheet or board-type insulation, or
alternately, a foamed-in-place type of insulation. In one
embodiment of the current invention, these components are bonded to
each other to act compositely in providing flexural and shear
strength in resisting the lateral loading imposed on the walls by
the PTESM, as well as gravity loading, both due to the weight of
the PTESM and other interior components as further described
hereinafter, and also of external environmental loading in the
instances of exterior installations of the inventive enclosure.
Said external environmental loadings are discussed further
hereinafter. This design concept for said embodiment of the
sandwich panel is similar to that employed in structural insulated
panels, commonly known as SIPs, as used in the exterior envelope
construction of some buildings.
[0019] The aforementioned sandwich panel envelope components have
the thermal insulative resistance required to restrict heat loss
from the PTESM to acceptable values, as determined though economic
analyses that generally consider the following; cost savings though
reduced purchase requirements of conventional energy, enclosure and
system construction and installation costs, and calculated rates of
thermal energy loss though enclosure envelope components. Maximum
anticipated exposure temperature from contact with the heated PTESM
impacts on the aforementioned materials used for said sandwich
panel construction, namely, the interior facing panels, combination
structural and insulative core, and bonding adhesive(s). Given that
the panels for the inventive enclosure combine the structural
characteristics of the aforementioned SIP panels along with a high
temperature resistance necessitated by the relatively high
temperature potentially attainable in the storage medium, the said
panels for the inventive enclosure shall hereinafter be referred to
as HTSIP ("high temperature structural insulated panel") as an
abbreviated form of identification.
[0020] In a second embodiment of this invention the flexural and
shear strength requirements of the wall sections of the insulative
enclosure are provided by external structural framing against which
the sandwich wall panels are braced. Similarly, the floor panel can
be provided with additional structural support in the form of a
prefabricated but conventional floor framing assembly, or
alternately, a base slab, typically of concrete construction.
Depending on the height of wall, span of the floor, and weight and
lateral loading characteristics of the PTESM, it may not otherwise
be economically practical to provide the strength required to the
floor as in an HTSIP type assembly. In these cases the
non-structural sandwich panels shall hereinafter be referred to as
HTSANIP ("high temperature sandwich insulated panel") as an
abbreviated form of identification.
[0021] In another embodiment of the invention the insulative core
of said sandwich panels are constructed of multiple bonded layers
of different insulative materials such that adequate structural and
thermal performance is provided by the core in achieving the
required structural performance of said sandwich panels. Less
costly materials can then be used where maximum temperature
resistance requirements through the thickness of said insulative
core are reduced as a result of the temperature gradient that
naturally occurs through the sandwich panel assemblies with
increasing distance from the aforementioned and heated PTESM
[0022] In yet another embodiment of the current invention
additional sandwich panel layered components, comprising a high
temperature insulative layer and high temperature protective liner
panel in contact with the PTESM, are bonded to the prefabricated
insulated sandwich panel assemblies of the walls, floor and roof of
the enclosure, thereby providing added protection against
deterioration in the structural and/or thermal performance of the
sandwich panel assemblies as a result of the aforementioned
temperature gradient, and thus avoiding similar deterioration in
the structural and/or thermal performance of the enclosure as a
whole assembly.
[0023] In yet another embodiment of the current invention the
enclosure is provided with two separate prefabricated internal heat
transfer systems, with the "input" system consisting of one or more
heat transfer coils to transfer the thermal energy from the energy
source to the PTESM in the inventive enclosure, and the "output"
system consisting of one or more heat transfer coils to transfer
said stored energy to the end use application, or in some cases to
one or more intermediate energy transfer devices, such as an inside
water tank with relatively small thermal storage capacity in
comparison to the inventive enclosure.
[0024] Said "input" heat transfer systems can be one of a range of
alternative designs, namely in the form of piping for containment
of liquid as the heat transfer medium, ducting for containment of
hot air as the heat transfer medium, or electric resistance wiring.
Said "output" heat transfer systems are generally in the form of
piping for containment of liquid as the heat transfer medium. Where
the heat transfer system type is in the form of piping, external
fins attached to said piping may be provided to improve the
efficiency of energy transfer to or from the PTESM. Configuration
and construction of these heat transfer system elements are
designed to facilitate the placement of the PTESM with minimal risk
of damage to said elements during the process of filling the
inventive enclosure with said medium (media), and also to
preferentially transfer heat from storage areas of higher
temperature of said medium (media) within the inventive enclosure
rather than from storage areas of lower temperature of said medium
(media). In one embodiment of the invention the aforementioned
prefabricated structural sandwich panel assemblies are provided
with insulative sleeves (16) at the locations where the
aforementioned piping, wiring, and ducting of the associated
aforementioned thermal energy transfer device(s) penetrate said
sandwich panels, thus providing protection to portions of the
insulative core that may otherwise be damaged if exposed to direct
contact with the heated inlets and outlets of the heat transfer
devices.
[0025] In another embodiment of the invention the enclosure is
provided with one or more heretofore identified cylindrical
metallic fabrication(s) extending vertically between the interior
faces of the floor and roof sandwich panels of the inventive
enclosure to allow separation of different PTESM grades, thereby
providing additional benefits as summarized below; [0026] The
separation of PTESM grades as noted better optimizes the use of the
different performance characteristics of the storage media both
inside and outside the barrier created by said cylindrical
fabrication(s). A preferred grade of PTESM for placement inside the
confines of said cylindrical fabrication(s) is one such that a
balance is provided in the cost of the medium and in reducing the
potential for damage to the heat transfer coils positioned within
said fabrication(s) during the PTESM filling process, or during the
removal of the PTESM in the event servicing of said coils is
required, while still providing adequate heat transfer
capabilities, such as with sand. A preferred grade of PTESM for
placement outside the confines of said cylindrical fabrication(s)
is one, different from the aforementioned "inside" grade, such that
a balance is provided in the cost of the medium and in maximizing
both heat transfer efficiency and thermal energy storage capacity,
such as with gravel. [0027] Servicing and removal of the heat
transfer coils positioned within said cylindrical fabrication(s) is
facilitated through the ability to remove just the PTESM material
within said fabrication(s) by suction or other process, and leaving
undisturbed the PTESM material occupying the space between said
cylindrical fabrication(s) and the inside faces of the
enclosure.
[0028] In another embodiment of the invention the enclosure is
provided with conduit propitiously positioned within the interior
space to accommodate wiring and temperature sensor devices for the
purpose of recording process data and providing data to the process
control system employed in managing the heat transfer processes
involved.
[0029] The inventive enclosure can be pre-assembled, or made
available in kit form, with the previously described HTSIP and/or
HTSANIP components prefabricated for ready assembly in a location
remote from the area of said fabrication. In various embodiments of
the invention, the other heretofore-described ancillary components
can be included in said kit.
[0030] Although the inventive enclosure is suitable for use in a
variety of environments, including residential, institutional,
commercial and industrial, the anticipated highest demand is in
residential applications, and more specifically, in active solar
heating systems, for either DHW heating or space heating, or both
combined. In such solar heating systems, the PTESM in the enclosure
is heated by conventional solar collectors, with temperature
regulation by a compatible conventional control system as typically
used in solar heating systems employing storage tanks for
containment of water or other liquids as the means of storing the
thermal energy. The PTESM is able to take greater advantage of the
higher temperature capabilities of some designs of collectors, such
as "vacuum tube-" or "evacuated tube"-type solar collectors, in
comparison to what is practical in the storage of water in
conventional hot water storage tanks. In addition to heating
applications, the enclosure is also able to provide thermal energy
in powering the refrigeration cycle by means of thermally-driven
coolers in space cooling systems.
[0031] A number of parameters in the design of the inventive
enclosure and aforementioned ancillary components can be varied and
thus accordingly impact thermal energy storage capacity and
efficiency. These parameters include overall enclosure size and
thermal insulative resistance of the HTSIP envelope, thermal
characteristics of the PTESM, and design specifications of the
internal heat transfer coils.
[0032] In numerous applications, such as in solar-based residential
combined DHW and space heating systems, significantly greater
thermal energy storage capacity is typically achievable with the
inventive enclosure than with traditional water tank storage. To
illustrate this point, the theoretical thermal energy storage
capacities of typical configurations in each of the two storage
systems were calculated.
[0033] Interior measurements of the inventive enclosure were taken
as 1800 mm.times.2400 mm.times.1800 mm for comparison to a 760
litre (200 US gal) water storage tank, generally considered a
"large" tank for a residential system, and one more likely to be
used for combined DHW and space heating rather than just DHW alone,
a more common configuration. The PTESM for the inventive enclosure
was assumed to be silica sand with a specific heat value of 1,280
kJ/m.sup.3 K, in comparison to water, with a comparable value of
4,180 kJ/m.sup.3 K. Maximum operating temperatures of 125.degree.
C. and 90.degree. C. were assumed for the inventive enclosure and
storage tank respectively, in consideration of the higher
temperature capabilities typically achievable with the PTESM in the
inventive enclosure. A common reference ambient temperature of
35.degree. C. was assumed as the minimum useful temperature for
heating purposes. Based on the foregoing parameters and including
an allowance for reduced thermal storage capacity due to the space
occupied within the inventive enclosure by heat transfer coils and
other peripherals, the theoretical thermal energy storage
capacities were determined to be 866 MJ (240 kw-hr) and 170 MJ (47
kw-hr) for the inventive enclosure and water storage tank
respectively relative to the base thermal energy content at the
assumed common ambient temperature in the two sample systems as
described.
[0034] Obviously the difference in thermal energy storage
capacities would be even greater for a smaller water storage tank
more typical for this application, particularly in a residential
system. Such a difference may influence the decision regarding
degree of conversion to a more environmentally sensitive energy
system; potentially even to the extent it could be determined not
to proceed with the conversion in the first place. As previously
noted, the size of the inventive enclosure and associated volume of
PTESM can be varied over a wide range with minimal increased risk
resulting from the increased thermal storage capacities, in
contrast to the situation with water storage based systems, as
discussed heretofore, and further hereinafter.
[0035] The enclosure is adaptable to either an interior or exterior
site installation. In an exterior installation, the basic inventive
enclosure structure is typically protected from weather elements by
means of conventional roof and wall sheathing and other
conventional cover materials. In the case of the enclosure being
constructed of HTSIP elements, as heretofore defined, the said
enclosure also forms the base structural element in resisting the
additional imposed design loadings of an environmental nature.
Aesthetic requirements can be met in those instances through the
selection of appropriate cover materials and trim elements,
including facade-style window and door elements, and by tailoring
the shape of the visible "building" as desired, thereby providing
an appearance that is complementary to the site and adjoining
buildings.
[0036] An additional benefit of an exterior setting for a solar
energy installation utilizing the inventive enclosure as noted
above is that of the roof providing a convenient and preferential
location for solar collector mounting that is more-readily
accessible than is often typically the case, in turn allowing for
improved access for inspection and maintenance of said collectors,
along with the possibility of adjusting the orientation of said
roof to maximize the solar radiation collection efficiency of said
collectors.
[0037] The invention provides several advantages over existing hot
water storage systems in many potential applications; [0038] As
discussed heretofore, thermal energy storage capacity can be more
easily varied over a larger range thereby increasing the potential
for greater storage for periods of darkness and low solar
radiation, thereby yielding increased savings through greater
reductions in conventional energy costs. [0039] The concern over
liquid spillage of the storage medium is eliminated, other than the
potential risk of a smaller amount of PCM if used as replacement
for some fraction of the PTESM. Although in those systems employing
liquid-type solar collector systems, process fluids at high
temperatures still exist in the heat transfer piping systems and in
possible auxiliary equipment, such as an optional intermediate
small energy transfer tank that can be used in the heat exchange
system serving the end-use application, the total volume of hot
fluids is significantly reduced. When the inventive system is used
in conjunction with off-peak electrical generation, concern over
liquid spillage is limited to just that of the circulating liquid
type heat recovery system employed in the recovery of thermal
energy from the PTESM of the inventive enclosure. [0040] Higher
insulation levels can more easily be provided for with the
inventive enclosure in comparison to that practically achievable
with conventional hot water storage tank installations. [0041] The
maximum temperature of the storage medium can typically be
increased in comparison to water-based storage, although it is
recognized that this advantage is offset to some degree by the
lower specific heat capacity of many potential common medium
materials, such as sand, in comparison to water.
[0042] In addition to the aforementioned advantages over
alternative existing designs, the inventive enclosure incorporates
other features that increase the practicality of the form of
thermal energy storage it affords to many potential users of said
energy as follows: [0043] The invention can be readily retrofitted
to existing houses. As heretofore noted, the enclosure can be
installed in either an interior or exterior setting. In further
variations of site selection options, it can be located inside an
existing or proposed building that is outside the main residence,
such as a detached garage structure, with the connective piping to
the end use structure typically insulated and routed through burial
in a trench or in some other effective manner. [0044] The enclosure
can accommodate a range of PTESM materials. Sand and gravel are
considered the most economical relative to initial cost, however
other materials may prove to be more cost effective taking into
consideration thermal capacity and alternative energy costs. As
previously noted one alternative to further increase storage
capacity for a given enclosure is in the use of PCMs as a
replacement fraction of the PTESM mass.
[0045] The prefabricated nature of the construction, including the
integral and appropriately-configured heat transfer system
assemblies, utilizing materials specifically selected to meet
necessary thermal, structural, and aesthetic requirements, along
with the other advantages afforded by the inventive enclosure, as
heretofore outlined, in satisfying the energy demands of the
heating and/or cooling system(s) of the end use application are
considered key elements in the novelty of the invention. The
enclosure system thus has considerably greater practicality,
including economic viability, for construction by the typical
end-user, either with assistance from a contractor, or as a "do it
yourself" project, than the alternative of attempting to construct
a system utilizing similar concepts but without the benefit of the
engineering design or prefabrication of required components
[0046] Other advantages and features of the invention will become
more apparent from the following description and the accompanying
drawings which are illustrative of preferred embodiments of the
invention claimed herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0047] Drawings which illustrate embodiments of the invention and
included herein are as follows;
[0048] FIG. 1 is a sectional view taken at a vertical plane through
the basic embodiment of the invention with a single grade of core
insulation (2) and depicting heretofore described "input" heat
transfer coil (14) and "output" heat transfer coil (15) in
schematic form along with the insulative sleeves (16) of the
penetrations of the supply and return piping (14a, 15a) for said
heat transfer coils where penetrating the HTSIP or HTSANIP of the
enclosure wall
[0049] FIG. 2 is a sectional view taken at a horizontal plane
through another embodiment of the current invention with a dual
grade of core insulation (2, 5) in the heretofore described HHTSIP,
and depicting heretofore described "input" and "output" heat
transfer coils in schematic form, with the heretofore described
metallic cylindrical fabrication (17) and two different and
isolated grades of PTESM (18, 19)
[0050] FIG. 3 is a sectional view through the same embodiment of
the current invention as in FIG. 2 above but with the view taken at
a vertical plane through the invention.
[0051] FIG. 4 is a sectional view through an abutting corner of
vertical and horizontal HHTSIP panels illustrating the dual grade
nature of core insulations (2, 5), and the thermal break detail
(11b) heretofore described at said corner.
[0052] FIG. 5 is a sectional view at the junction of connecting
side edges of abutting HHTSIP panels illustrating the thermal break
detail (11a) heretofore described at said junction, and also
depicting the embodiment of said panel where two grades of
insulation (2a, 2b) are bonded to form a structural core such that
adequate structural and thermal performance is provided by the core
in achieving the required structural performance of said sandwich
panels as a whole, but permitting less costly insulative material
to be used where maximum temperature resistance requirements
through the thickness of said insulative core are reduced as
heretofore described.
[0053] FIG. 6 is a sectional view taken at a vertical plane through
an embodiment of the current invention as in FIG. 3 above but
depicting the installation in an exterior location with
weatherproofing additions to the inventive enclosure, and in this
embodiment depicting separate external structural floor support
(26) as heretofore described as a possible preferred or required
element.
[0054] FIG. 7 is an elevation view depicting the installation of
the inventive enclosure in an exterior location as in FIG. 6 but
with the inventive enclosure hidden by standard "outbuilding" type
features such as wall siding (23), roof structure and facade style
window (24) and door (25) elements, in satisfying additional
aesthetic preferences, in addition to contributing to the weather
resistant functionality of said building.
[0055] The basic embodiment of the previously-defined HTSIP
assembly as illustrated in FIG. 1 consists of a minimum of three
layers, namely an outside facing panel (1), a middle insulative
core (2), and an interior liner panel (3). The layers are bonded
together with adhesive (4) with the strength required to allow the
layered assembly to act compositely in resisting the imposed
structural loadings as heretofore described. In another embodiment
of the current invention the insulative core is self-bonding to the
facing panels, as in the case of a foamed-in-place polyurethane
grade insulation, and said adhesive is thereby not required. It is
critical that the composite assembly maintains adequate strength at
the maximum exposure temperatures anticipated at each interface and
depth throughout the thickness of the assembly. The most severe (ie
highest) exposure temperature occurs at the interface of the PTESM
and the interior liner panel (3), and decreases through the
thickness of the various layers in the HTSIPs of the inventive
enclosure to a minimum at the exterior surface of the outside
facing (1).
[0056] The interior facing (3) can be a rigid panel such as
fiber-reinforced cement board, or other panel product with adequate
strength properties at the higher temperatures anticipated from
exposure to the heated PTESM. The insulating core (2) can be one of
a variety of products that provides the desired combination of
mechanical and insulative properties at the maximum design
operating temperature, such as polyisocyanurate foam and cellular
glass rigid insulations. The exterior facing (1) can be a rigid
panel such as plywood, or other engineered wood product,
fiber-reinforced cement board, or other similar product with
adequate mechanical properties. This embodiment of the HTSIP shall
hereinafter be identified as the basic HTSIP.
[0057] In one embodiment of the current invention, per FIGS. 2-6,
where dictated by the maximum operating temperature in the PTESM,
the basic HTSIP assembly described above (1, 2, 3, 4) is provided
with additional protection against said temperature consisting of
an additional layer of high-temperature-resistant insulation (5),
such as cellular glass or mineral fiber type and a separate high
temperature liner panel (6) in direct contact with the PTESM (19).
These additional layers are bonded together with suitable high
temperature adhesive (7), and to the internal facing panel of said
basic HTSIP with heretofore described adhesive (4). In this
embodiment of the current invention it is possible that the rigid
structural panel thereby positioned in the interior of the sandwich
panel assembly (3), and provided with the additional thermal
protection heretofore described, can in some cases be a wood-based
product such as plywood or OSB whereby required strength properties
are maintained at the maximum anticipated operating temperature at
that location in the assembly. As heretofore noted, it is also
possible that depending on the temperature gradient though the
thickness of said embodiment of the sandwich panel assembly, a
polystyrene or other grade of insulation with lower maximum
operating temperature capability but also less costly grade can be
used as the structural core element (2), or as the outer layer (2b)
in a bonded multi-layer structural core in the heretofore described
HTSIP assembly and contributing to the strength requirements of
said panel. This bonded multi-layer structural core (2a, 2b) is
illustrated in the embodiment depicted in FIG. 5. This structural
sandwich panel assembly with even higher temperature resistance
then becomes another embodiment of the HTSIP assembly, and is
hereinafter identified as HHTSIP (Higher High Temperature SIP).
[0058] The panels are connected along their edges using structural
angle sections (8) predrilled at pre-determined spacings and
fastened to adjoining panels along their edges with conventional
screw type fasteners (9) of the design size and strength required
to resist the loading imposed by the PTESM. In some embodiments of
the current invention a wood spacer (10) is installed along the
edges of the panel assembly to further stabilize this connection
when required
[0059] An important feature of the edge detail of the HTSIP
assembly, as shown by FIG. 1, is that the edge of the foam core is
shaped (11) to minimize thermal bridging though the thickness of
the panel assemblies in this connecting corner region of abutting
panels of the inventive enclosure. As further security in
maintaining this thermal break and guarding against thermal energy
loss at said connecting areas, a strip of high temperature
blanket-type insulation (12) in the range of 3 mm thick is inserted
in said corner region during the assembly process of the inventive
enclosure.
[0060] Similar to the low thermal bridging objective of the HTSIP
assembly detail referenced above, a thermal break is also
incorporated in the HHTSIP assembly (11b) as illustrated in FIG. 4
in the layer of high-temperature insulation (5) as a means of
reducing the maximum temperature exposure to the basic HTSIP
assembly component of the HHTSIP assembly heretofore described.
[0061] In addition to the construction measures adopted at
connecting corner regions heretofore described, in some embodiments
of the inventive enclosure, as illustrated in FIGS. 1 and 4, the
outer panel facing (1b) of the horizontal roof HTSIP or HHTSIP is
extended beyond the outermost contact edge of the outer vertical
panel facing of the side wall (1), with said extension (1c) being
in the range of 10 mm. In these embodiments, a horizontal spacer
strip (13), typically of wood or plastic material, is installed
against the top and bottom edges of the vertical HTSIPs and secured
by the aforementioned structural angle sections (8) and attendant
securing fasteners (9) to maintain the necessary relative
positioning of the roof and floor panels with the vertical wall
panels of the inventive enclosure. These design details aid in the
assurance of full load bearing in the transmittal of gravity
loading through the roof panel (1b) to said vertical panels of the
inventive enclosure. The security of this load transfer detail
becomes even more critical when the inventive enclosure is
installed outdoors, with said enclosure providing the structural
support in resisting additional loading to that of a typical indoor
installation, namely the dead loads of the external roof
construction and any solar collector units and associated framing
mounted on said roof, and live loads imposed by snow and wind as
pertinent to the geographic region of the enclosure
installation.
[0062] Where the size of the inventive enclosure is such that
multiple HTSIP or HHTSIP panels are required for one or more sets
of opposite faces of the enclosure, an edge detail (11a) similar to
that of FIG. 5 is provided to minimize thermal bridging through
connecting side edges of abutting panels. As heretofore noted in
the case of the corner edge junctures of the inventive enclosure, a
strip of high temperature blanket type insulation (12a) in the
range of 3 mm thick is also inserted in the joint of said
connecting side edges as added insurance against thermal
bridging.
[0063] As heretofore noted, in one embodiment of the current
invention, the flexural and shear strength requirements of the
HTSANIP wall sections of the inventive enclosure are provided by
external structural framing (13a) against which the sandwich wall
panels are braced, as illustrated in FIG. 3. Said framing can be
conventional construction, as in the use of lumber components, with
the loading from the inventive enclosure transferred from said
sandwich wall panels by some standard structural element as a
filler panel (13b) possessing sufficient compressive rigidity.
[0064] In one embodiment of the current invention input and output
heat transfer coils (14, 15) are selectively positioned and spaced
to optimize heat transfer into and from the PTESM. In the
embodiments shown in FIGS. 1, 2, 3 and 6, said heat transfer coils
are shown schematically as coiled piping, however the input heat
transfer coil(s) (14) can alternately be ductwork or electric
resistance wiring as heretofore noted. Said heat transfer coil
piping, ductwork or electric resistance wiring penetrate the
inventive enclosure walls in heretofore described insulative
sleeves (16) terminating at ends (14a) for input heat transfer
coil(s) and ends (15a) for output heat transfer coil(s), with said
terminations suitable for connection to the process system services
external to the inventive enclosure. Said insulative sleeves (16)
serve to minimize heat loss from the inventive enclosure, and as
with the HTSIP or HHTSIP assembly previously described, thereby
maintain adequate performance at the maximum design exposure
temperature anticipated.
[0065] As heretofore noted in this section, in one embodiment of
the current invention one or more metallic cylindrical
fabrication(s) (17) is provided to allow the use of two separate
grades of PTESM, typically a finer grade, such as sand (18), within
the boundary of said fabrication(s), and a coarser grade, such as
gravel (19), outside the boundary of said fabrication(s).
[0066] In another embodiment of this invention, one or more roof
HTSIP or HHTSIP assembly(ies) is designed to be removable to
facilitate access to the aforementioned heat transfer coils for
servicing without the dismantling of the entire inventive enclosure
thereby minimizing the amount of PTESM to be removed. In this case
the adjacent roof and wall HTSIPs or HHTSIPs that remain in
position adjacent to the temporarily removed panel(s), and
reinforced as required, provide the necessary stiffness and
strength in maintaining the overall dimensions and structural
integrity of the enclosure under the applied loadings that remain
during said servicing procedure.
[0067] In another embodiment of the current invention, heretofore
mentioned conduits (20) are positioned within the enclosure to
accommodate wiring and enable the secure embedment of temperature
sensor devices within the PTESM (18, 19) and within the insulative
layers of the envelope of the inventive enclosure itself (2, 5) if
desired, for the purpose of recording operating data and providing
data to the process control system that manages the heat transfer
processes involved. Fittings (21) are installed in said conduit at
the embedment locations for said sensors, as shown in FIGS. 3 and
6. Said conduits penetrate the walls of the inventive enclosure in
insulative sleeves similar to those heretofore described for heat
transfer device enclosure wall penetrations (16), with end
terminations (20a) compatible with exterior data collection and
control system wiring.
[0068] As heretofore indicated, when installed outside, the
inventive enclosure is protected from the environmental elements by
a weather resistant envelope, consisting of a roof structure (22),
siding and associated strapping (23), and with windows (24) and
doors (25) of a facade nature, all contributing to the presentation
of desired appearance in the form of a site-compatible
"outbuilding" as illustrated in FIGS. 6 and 7. In the embodiment
depicted in said figures a separate external structural floor
support frame (26) as heretofore described is depicted in place
under the HHTSANIP floor panel assembly. Where the energy source is
solar, exposed roof space thus provided can serve as a preferred
area for mounting of solar collectors (27). The roof structure in
such construction can be made asymmetrical as shown schematically
in said figures to preferentially increase space available to said
collectors in a solar heating system. Maximizing solar exposure for
said collectors can thereby be achieved though combination of this
expanded roof surface and the selective orientation of said roof
surface. In this embodiment the inventive enclosure is designed as
the structural core of the structure in withstanding the additional
environmental loadings imposed in an exterior setting, as a means
of eliminating the need for additional structural elements and
their associated costs, thus contributing to the economic viability
of the inventive enclosure-based energy storage system. As
heretofore noted, other embodiments of the current invention
achieving similar functionality of the energy storage process are
achievable using HTSANIP panels in which exterior structural
framing is employed to resist the interior loading imposed by the
PTESM and also exterior loading on the structure from environmental
effects.
[0069] As will be apparent to those skilled in the art in light of
the foregoing disclosure, many modifications to the invention
described herein are possible without departing from the spirit and
scope thereof. Accordingly, the scope of the current invention is
to be construed in accordance with the substance of the claims as
defined in that section of the current application.
BEST MODE FOR CARRYING OUT THE INVENTION
[0070] Construction of the inventive HTSIP and HTSANIP enclosure
panels as heretofore described is accomplished using methods
essentially as employed in the construction of sandwich panels,
including structural insulated panels, such as are typically used
in the envelope construction of some buildings. These methods
include assembly of the sandwich panel layers, including the
insulative core sheet(s) and facings, and typically either using
adhesives and possibly heat in joining said components under
pressure, or in the utilization of a self-bonding grade of
insulation, as in the case of a foamed-in-place urethane grade. The
general methods employed in this process are thus well practiced
and understood, except that the various component materials must be
specifically selected for anticipated maximum design temperatures
and loadings, and other details such as connections and
penetrations require consideration of the end use application for
the current invention. It is significant that the maximum design
temperatures are typically greater than those encountered in said
building envelope applications. In the case of the HHTSIP panels as
heretofore noted, the basic procedure remains similar except that
an additional insulative layer is introduced to the sandwich panel
assembly as a means of further increasing it's maximum operating
temperature capability.
[0071] Also as heretofore noted the inventive enclosure with
attendant ancillary components can be pre-assembled to various
stages of completion, or the various components prefabricated in a
centralized manufacturing facility suitable for final assembly in
the field.
INDUSTRIAL APPLICABILITY
[0072] As heretofore noted, the inventive enclosure and associated
ancillary components have many potential applications where thermal
energy is required, whether that be in residential, commercial,
institutional or industrial applications. It is anticipated however
that the most widely targeted application will be for space heating
systems and DHW heating systems in single- and multi-residential,
institutional and light commercial situations and also for heating
the water of swimming pools and similar facilities. Also as noted
heretofore, the energy source most widely anticipated to be
utilized with the inventive enclosure applications is solar,
although said enclosure is also suitable for use in storage of
thermal energy from an electrical source, generally in off-peak
generation/time-of-use applications. In addition however the
thermal energy retained in the enclosure can also be used in
powering the refrigeration cycle by means of thermally-driven
coolers in space cooling systems.
* * * * *