U.S. patent application number 15/758865 was filed with the patent office on 2018-10-04 for a system and method for cooling a space utilizing thermal energy storage.
The applicant listed for this patent is NETENERGY (NAIM ENERGY TECHNOLOGIES, LLC). Invention is credited to Said Al-Hallaj, Siddique Ali Khateeb Razack, YORAM SHABTAY.
Application Number | 20180283709 15/758865 |
Document ID | / |
Family ID | 58239692 |
Filed Date | 2018-10-04 |
United States Patent
Application |
20180283709 |
Kind Code |
A1 |
Al-Hallaj; Said ; et
al. |
October 4, 2018 |
A SYSTEM AND METHOD FOR COOLING A SPACE UTILIZING THERMAL ENERGY
STORAGE
Abstract
A system and method of using the system is provided for cooling
a building space through the use of thermal storage and release of
energy by charging and discharging a phase change material
comprising low temperature wax.
Inventors: |
Al-Hallaj; Said; (Chicago,
IL) ; Khateeb Razack; Siddique Ali; (Darien, IL)
; SHABTAY; YORAM; (PROSPECT HEIGHTS, IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
NETENERGY (NAIM ENERGY TECHNOLOGIES, LLC) |
Chicago |
IL |
US |
|
|
Family ID: |
58239692 |
Appl. No.: |
15/758865 |
Filed: |
September 9, 2015 |
PCT Filed: |
September 9, 2015 |
PCT NO: |
PCT/US2015/049144 |
371 Date: |
March 9, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F28F 27/00 20130101;
F28F 21/085 20130101; F28D 20/021 20130101; F25B 2400/04 20130101;
F28D 7/087 20130101; Y02E 60/147 20130101; F28F 21/02 20130101;
F24F 2005/0032 20130101; F25B 2400/19 20130101; F28D 1/06 20130101;
Y02E 60/145 20130101; F25B 2400/24 20130101; F28D 20/023 20130101;
F24F 2140/20 20180101; F24F 5/0021 20130101; F28D 2020/0013
20130101; F25B 41/04 20130101; F28D 2020/0021 20130101; F24F
2110/10 20180101; F28D 20/026 20130101; F24F 5/001 20130101; F28D
2021/0071 20130101; Y02E 60/14 20130101 |
International
Class: |
F24F 5/00 20060101
F24F005/00 |
Claims
1.-27. (canceled)
28. A refrigerant based thermal energy storage and cooling system,
comprising: a refrigeration cycle comprising an air conditioner
condensing unit having a compressor, a condenser, an expansion
valve, and an evaporator through which refrigerant runs; a thermal
energy storage ("TES") unit in thermal communication with a
refrigerant, wherein the TES unit comprises a phase change material
("PCM") which stores and releases thermal energy, and a refrigerant
coil through which a refrigerant runs, wherein the PCM comprises a
low temperature wax; a plurality of valves for diverting the system
between a charging cycle and a discharging cycle; an insulating
apparatus which insulates the PCM and refrigerant coil of the TES
unit to avoid heat dispersion; a refrigerant for transferring
thermal energy to and from the compressor, condenser, expansion
valve, evaporator and the PCM of the TES unit through a refrigerant
management system; a refrigerant management system for delivering a
refrigerant through the system comprising a plurality of valves and
tubes; a ventilation system comprising an air inlet and an air
outlet disposed in thermal communication with the PCM of the TES
unit, and a propeller device; and a thermal control system for
controlling the thermodynamics of the system, wherein the
refrigeration cycle can operate alternative to the charging cycle,
wherein the refrigeration cycle can operate alternative to the
discharging cycle, wherein the refrigeration cycle can operate
simultaneously when the system is in charging cycle, and wherein
the refrigeration cycle can also operate simultaneously when the
system is in discharging cycle.
29. The system as in claim 1, further comprising a plurality of
external TES units each comprising a PCM, a refrigerant coil and an
external insulating apparatus and wherein the plurality of valves
are configured to provide at least one of the PCMs of the external
TES units and the PCM of the TES unit with at least one of charging
cycle, discharging cycle, simultaneous discharging cycle and
refrigeration cycle, and simultaneous charging cycle and
refrigeration cycle.
30. The system as in claim 1 whereby the PCM is in the discharging
cycle while simultaneously the refrigeration cycle is operated.
31. The system as in claim 1 whereby the PCM is in the charging
cycle simultaneously with the refrigeration cycle.
32. The system as in claim 1 further comprising a plurality of
liquid pumps.
33. The system as in claim 1 wherein the refrigeration coil is made
from a thermally conductive material selected from the group
consisting of copper, copper alloys, gold, silver, carbon alloys,
aluminum, and alloys thereof.
34. The system as in claim 1 wherein the PCM of the TES unit
further comprises at least one from the group consisting of
graphite, and graphite and aluminum oxide.
35. A phase change material composite for use in thermal energy
storage comprising: a low temperature wax; and a porous matrix
material which provides structure to a composite configuration,
wherein the porous matrix material is at least one selected from
the group consisting of expanded graphite, aluminum oxide, graphite
powder, carbon fibers, graphite/carbon nano-powders/nano-fibers,
copper, aluminum powder and conductive foam.
36. A method of cooling an environment using the system as in claim
1, comprising the steps of: providing a PCM further comprising at
least one material from the group consisting of graphite and
aluminum oxide, in thermal communication with a charging coil
through which the refrigerant passes in the refrigerant management
system; activating a charging cycle whereby the PCM is charged with
the cooled refrigerant; sensing the charged state of the PCM using
a sensor; ceasing circulation of the refrigerant through the
charging cycle when the PCM is determined to be charged; activating
a discharging cycle whereby the environment is cooled by passing
air through the air inlet of the ventilation system, past the PCM,
and out of the air outlet; establishing a threshold level for
activating at least one of the refrigeration cycle and the charging
cycle; monitoring at least one from the group consisting of the
temperature of the air exiting the air outlet, the phase state of
the PCM, and the temperature of the PCM; and upon reaching a
threshold level, delivering the refrigerant through at least one of
the refrigeration cycle and the charging cycle, wherein the
refrigeration cycle can operate simultaneously with one selected
from the group consisting of the charging cycle and the discharging
cycle.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a system and method for
cooling a space utilizing thermal energy storage. More
specifically, the invention relates to a system and method for
cooling a space through the use of thermal energy storage and the
release of thermal energy by utilizing a phase change composite
comprising of a phase change material.
BACKGROUND
[0002] For buildings located in warm climates, electricity bills
can be quite high due to energy consumption to cool these spaces
during peak hours of heat. In the case of restaurants, peak hours
are often during breakfast, lunch and dinnertime. In such peak
hours, electricity prices are particularly high. On the other hand,
during off peak and low cooling hours an air conditioning
compressor unit operates at a high coefficient of performance,
therefore necessitating lower energy consumption since the energy
necessary to reduce the heat is small in proportion to the
compressor's operating power, thereby passing lower costs to the
owners. In some cases during peak hours electricity price can be
0.05-0.07 $/kWh higher than during off-peak periods.
[0003] Traditional cooling systems for commercial buildings are air
conditioning units run continuously throughout the day. These
buildings need to be cooled mainly during the day but units that
run continuously ultimately result in high consumption costs and
low energy efficiency.
[0004] Methods to store thermal energy for cooling purposes have
been designed in order to try to manage the increasing demand for
high-peak power consumption, while at the same time, minimizing
power expenses. The goal is to save power consumption and cost in
these systems by the release of previously stored cold thermal
energy. Attempts have been made to create hybrid systems that
include traditional air conditioning units along with thermal
energy storage systems.
[0005] One such hybrid system utilizes ice, for example. The use of
ice, however, provides for an inefficient re-charge of the cooling
system when it is melted. Using more ice for better performance, in
fact, requires more volume and space, an impractical solution.
Water/ice, offers a slow response to storing and releasing cold
thermal energy due to a much lower thermal conductivity. Ice only
melts at 0.degree. C. Clearly, problems remain with overall
performance and capacity.
[0006] An effective and cost-efficient solution is needed for
managing peak and off-peak times in an energy efficient manner, and
therefore effectively reducing costs. Moreover, a system is needed
which is simple to implement and to customize to systems already
present in pre-existing commercial spaces.
SUMMARY OF THE INVENTION
[0007] The present invention is related to a system for cooling a
space of any size utilizing thermal energy storage ("TES") wherein
a phase change material composite ("PCC") comprising a phase change
material ("PCM") and one or more thermally conductive materials or
a PCM alone is coupled to an existing air conditioning refrigerant
cycle to cool an environment.
[0008] The present invention is also related to a system that can
store cold energy during the night by means of an electrically
driven air conditioning unit and a TES unit comprising a PCC or a
PCM alone, when electricity prices can be much lower than during
the day, and use the energy stored in the TES unit's PCM during the
day when electricity prices can be high, while allowing the
electrically driven air conditioning unit to rest thus allowing
energy and cost savings.
[0009] The present invention is related to a system having a PCM
that can absorb a high amount of energy while changing from a
liquid to a solid phase and release energy while changing from a
solid to a liquid phase.
[0010] The present invention relates to a method for cooling an
environment or space by routing hot air circulating from the
environment to be in thermal communication with a PCC or a PCM
alone which has been previously charged during a refrigeration
cycle, thus cooling the air.
[0011] The present invention is further related to a method for
cooling an environment or space by using low temperature wax along
with graphite, a highly thermal conductive material, which offers
much faster charging/discharging periods.
[0012] The present invention is even further related to a system
which can be adapted to different applications and operative needs
by customizing the composite in the phase change material composite
and therefore provide appropriate melting points.
[0013] The present invention is also related to a system which can
be adapted to currently existing air conditioning condensing
units.
[0014] The present invention is further related to a system
configured to have existing air conditioning units and a plurality
of thermal energy storage modules function simultaneously or
alternatively for cooling.
[0015] The present invention is moreover related to a system that
can be implemented at low cost and with low space and volume
requirements.
[0016] The present invention is even further related to a system
that is simple to install and can be customized to the type of
existing or new air conditioning condensing unit and ventilation
system needed or already present.
[0017] The present invention is related to a system in which PCMs
and PCCs can be in various configurations which enable the storage
and release of thermal energy, for example, wrapped or even poured
around the refrigerant conduit pipes of the refrigerant coil, or be
incorporated into panels in thermal communication with the
refrigerant coil.
[0018] The present invention is also related to a system which can
utilize pre-existing air conditioning units to provide a more
efficient solution for cooling.
[0019] The present invention is further related to a system having
a thermal control system which can be automatically changed,
manually changed, or be programmable to adjust for desired
environmental temperatures.
[0020] These and other features of the present invention are
further described in the section entitled the Detailed Description
of the Drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 illustrates an embodiment of the system in accordance
with the principles of the present invention;
[0022] FIG. 2 illustrates another embodiment of the system in
accordance with the principles of the present invention;
[0023] FIG. 3 illustrates yet another embodiment of the system in
accordance with the principles of the present invention;
[0024] FIG. 4 illustrates still another embodiment of the system in
accordance with the principles of the present invention;
[0025] FIG. 5 illustrates an embodiment of a PCC of the TES unit of
the system in accordance with the principles of the present
invention;
[0026] FIG. 6 illustrates still another embodiment of the system in
accordance with the principles of the present invention;
[0027] FIG. 7 illustrates an embodiment of the TES unit of the
system in accordance with the principles of the present
invention;
[0028] FIG. 8 illustrates an embodiment of the TES unit of the
system in accordance with the principles of the present
invention;
[0029] FIG. 9 illustrates an embodiment of the system in accordance
with the principles of the present invention; and
[0030] FIG. 10 illustrates yet another embodiment of the system in
accordance with the principles of the present invention.
DETAILED DESCRIPTION OF THE DRAWINGS
[0031] The following detailed embodiments presented herein are for
illustrative purposes. That is, these detailed embodiments are
intended to be exemplary of the present invention for the purposes
of providing and aiding a person skilled in the pertinent art to
readily understand how to make and use of the present
invention.
[0032] Accordingly, the detailed discussion herein of one or more
embodiments is not intended, nor is to be construed, to limit the
metes and bounds of the patent protection afforded the present
invention, in which the scope of patent protection is intended to
be defined by the claims and equivalents thereof. Therefore,
embodiments not specifically addressed herein, such as adaptations,
variations, modifications, and equivalent arrangements, should be
and are considered to be implicitly disclosed by the illustrative
embodiments and claims described herein and therefore fall within
the scope of the present invention.
[0033] Further, it should be understood that, although steps of
various claimed methods may be shown and described as being in a
sequence or temporal order, the steps of any such method are not
limited to being carried out in any particular sequence or order,
absent an indication otherwise. That is, the claimed method steps
are considered capable of being carried out in any sequential
combination or permutation order while still falling within the
scope of the present invention.
[0034] Additionally, it is important to note that each term used
herein refers to that which a person skilled in the relevant art
would understand such term to mean based on the contextual use of
such term herein. To the extent that the meaning of a term used
herein, as understood by the person skilled in the relevant art
based on the contextual use of such term, differs in any way from
any particular dictionary definition of such term, it is intended
that the meaning of the term as understood by the person skilled in
the relevant art should prevail.
[0035] Furthermore, a person skilled in the art of reading claimed
inventions should understand that "a" and "an" each generally
denotes "at least one," but does not exclude a plurality unless the
contextual use dictates otherwise. And that the term "or" denotes
"at least one of the items," but does not exclude a plurality of
items of the list.
[0036] FIG. 1 illustrates an embodiment of the system 10 of the
invention. The system in FIG. 1 has a refrigeration cycle 30, a
thermal energy storage ("TES") unit 20, a ventilation system 50,
and a thermal control system 40.
[0037] The refrigeration cycle 30 and the TES unit 20 are
thermodynamically connected via a refrigerant 1 running through a
refrigerant management system which includes tubes 3, valves and
one or more liquid pumps. In this embodiment, the refrigerant 1 is
housed in a tube 3 and is pumped through the system 10 by a liquid
pump 2.
[0038] The liquid pump 2 can be any liquid pump known in the art to
move refrigerant through a heating ventilation and air conditioning
("HVAC") system. The liquid pump 2 can be placed at any position
along the loop that guarantees the movement of the refrigerant 1
through tubes of a refrigerant management system. If required
additional pumps can be implemented. The liquid pump 2 pumps low
pressure refrigerant 1 in the form of gas into a compressor 11 of
the refrigeration cycle 30. The refrigerant 1 then increases in
pressure through the compressor 11 and is moved into a condenser 12
where the refrigerant 1 assumes a liquid phase under high pressure,
while heat is released to the environment. Also provided is an
expansion valve 13, which is located after the condenser 12 in the
refrigeration cycle 30, and in use, lowers the pressure of the
refrigerant 1 after it leaves the condenser 12. The expansion valve
13 can be any type of valve understood by a person skilled in the
art to lower the pressure of a refrigerant, such as a solenoid
valve. In some embodiments the compressor 11 alone could suffice in
terms of moving the refrigerant 1 along the loop; therefore a
liquid pump 2 could be not necessary.
[0039] The refrigerant cycle 30, when in use, cools the
refrigerant, which then enters the TES unit 20, thereby
thermodynamically connecting the refrigeration cycle 30 and the TES
unit 20.
[0040] The refrigerant 1 leaves the expansion valve 13 in a tube 3
of the refrigerant management system in a cold liquid state, and
enters the inlet 24 of the TES unit 20 and into its refrigerant
coil 22. The TES unit 20 also comprises a phase change material
("PCM") 21 in thermal communication with the refrigerant coil 22
and ultimately the refrigerant 1 therein. The PCM could be a phase
change material composite ("PCC"), or could be the PCM only. Since
either form of PCM is contemplated to be included in a TES unit 20
of the present invention, PCM will be used for referring to both
PCC and PCM, unless otherwise stated.
[0041] In use, the refrigerant 1 enters the inlet 24 of the TES
unit 20 and is pumped through the refrigerant coil 22. The
refrigerant coil 22 is either surrounded by or adjacent to the PCM
21 whereby the refrigerant 1 is in thermal communication with the
PCM 21. The PCM 21 can be arranged, for example, in a plurality of
slabs (see FIGS. 7 and 8 as one of the possible slabs
configurations), through which the refrigerant coil 22 extends. In
one embodiment, the refrigerant coil 22 can be made of copper and
can exist in the PCM in a serpentine coil disposition. The
refrigerant 1 exits the refrigerant coil 22 from the outlet 25. The
refrigerant coil 22 can also be any other material which is
conducive to the thermal transfer of energy from the refrigerant to
the PCM and vice versa.
[0042] The refrigerant 1 can be any phase change material commonly
known and commonly used in the art to run through HVAC systems, for
example, but not limited to, water and Freon.TM. (halo-carbon
product or hydro fluoro-carbons), propylene glycol or any
combination thereof. If the refrigerant 1 is water/glycol, then in
the embodiments of the system 10, the condenser is replaced by a
chiller. Moreover, if the refrigerant 1 is water/glycol no
expansion valve 13 is required (see e.g. FIG. 9). If the
refrigerant 1 is Freon, then in the embodiments of the system 10,
the liquid pump is not required (see e.g. FIG. 10).
[0043] A PCM is a thermal energy storage medium. The amount of
energy stored or released by the PCM is called `latent heat of
fusion`. Thermal energy is stored by changing the phase of the PCM
from liquid to solid or by changing the internal energy.
Conversely, thermal energy is released as the material changes its
phase solid to liquid. PCMs are designed to present high latent
heat of fusion, melt and solidify at specified temperatures and are
capable of storing and releasing a large amount of thermal
energy.
[0044] An embodiment of the invention is supported by a TES unit 20
having a PCM 21, which is a low temperature wax, on its own in a
supporting structure, and it can be used for the thermal
conductivity in the system.
[0045] In another embodiment, the PCM can be a composite, also
referred to as a PCM composite ("PCC") including graphite. Aluminum
oxide or other conductive metals can be added to the composite in
order to further enhance thermal conductivity. A PCC can be
characterized by a wide range of melting points. By increasing the
number of atoms of carbon in the PCC it is possible to increase the
melting point and vice versa. Using different percentages of low
temperature wax and graphite, and potentially other materials in
the PCC, allows the system to operate at different efficiencies due
to the different melting points of the materials involved.
Therefore, the system allows for different applications and
operative needs by customizing the composite in the PCM and
therefore providing appropriate melting points.
[0046] A PCC uses expanded graphite as a supporting porous matrix
to hold the phase change material (low temperature waxes) together.
Commercially available expanded graphite (EG) is formed by an
intercalation reaction with various acids and subsequent heat
treatment. Commercial EG is uni-axially compacted using a pneumatic
press, or any commercially available press. Examples of pressing
pressures range at between about 10 to about 30 psi pressure, and
until bulky density of between about 170-about 200 Kg/m.sup.3 is
achieved. Different pressures can be applied to achieve different
densities. Afterwards, the compressed EG is submerged in a bath of
molten PCM (low temperature waxes), kept at a temperature of
between about 5-10.degree. C. higher than its melting temperature,
and left to soak until the PCM has reached its maximum absorption
into the graphite matrix.
[0047] EG density increases with the compaction pressure applied
and it can be varied in order to reach higher thermal conductivity.
Therefore, thermal conductivity increases with EG density whereas
the PCM latent heat of fusion reduces with EG density (lower EG
mass involved).
[0048] The PCC composition can for example be, but is not limited
to, between about 60-85% PCM, and between about 15-40% EG. These
percentages are not meant to be limiting, and the percentages can
vary according to the application and operative mode desired. Other
materials can also be used to replace EG in a PCC including, for
example, but not limited to graphite powder, carbon fibers,
graphite/carbon nano-powders/nano-fibers, copper, aluminum powder
and conductive foam such as carbon, graphite, copper and aluminum.
Other additives such as polymer can also be added to improve the
mechanical properties.
[0049] PCMs store or release thermal energy along with a phase
change over a prolonged period of time. A PCM is "charged" (and
related terms used throughout the application) when it stores cold
thermal energy and solidifies, and "discharges" (and related terms
used throughout the application) when it releases thermal energy
and changes phase from a more solid state to a more liquid state.
Some PCMs are more advantageous in the TES unit 20 of the system 10
than others. For example, a PCM composite including low temperature
waxes and graphite leads to a much faster charging time due to a
high thermal conductivity of graphite. Varying the percentages of
graphite and other conductive materials, and low temperature wax,
in the PCC leads to varying thermal conductivity that can be
tailored to different requirements. This is not possible for
traditional PCMs. The system 10 is therefore customizable to many
different applications and configurations.
[0050] Low temperature waxes are reliable, non-corrosive and
chemically inert below 500.degree. C. A system which has a
refrigeration cycle and TES unit as herein described is efficient
and therefore cheaper to operate than traditional air conditioning
units and refrigeration cycles coupled with water/ice thermal
energy storage modules. The use of a low temperature wax instead of
water/ice is much more efficient also because of a much higher
volumetric energy density (under some conditions more than 32
Wh/Lit compared to the 22 Wh/Lit) which translates into being able
to store a much larger amount of heat than water/ice energy storage
solutions.
[0051] Good high thermal conductivity is important in order to
guarantee fast charge and discharge rates. With a faster charge
rate the refrigeration air conditioning cycles need to operate, and
therefore consume electricity, for shorter periods of time.
Depending on the quantity of refrigerant flowing by the PCM, the
system presents fast charging rates. For instance, with refrigerant
transferring cold energy to the PCC at a pace of 1.86 GPH (gallons
per hour-energy rate equivalent to stored energy content), PCC
slabs can be cooled and store cold thermal energy in about 1 hour.
At 4.5 GPH (energy rate twice the rate of stored energy content), a
PCC can be expected to charge in 20 to 30 minutes, while at 12 GPH
(energy rate 3-4 times higher than stored energy content) the PCC
can fully charge in approximately 10 to 20 minutes.
[0052] Another important property presented by low temperature
waxes is negligible "super cooling", which is the possibility of
lowering the temperature of a material below its freezing point
without it becoming a solid. Without solidifying, the PCM cannot
store thermal energy. Therefore, the use of low temperature waxes
in the PCM and the PCC is advantageous because it experiences
negligible super cooling and can thus freeze and store thermal
energy.
[0053] Moreover, a PCC composed of low temperature wax and other
additives in different combinations has quite a long operative
life, possibly of more than 15 years, with an endurance to function
for more than 10,000 cycles continuously with an overall efficiency
between 80 and 95%.
[0054] Therefore, for comparable performances a much lower volume
of PCM is needed compared to other PCMs such as water/ice.
Moreover, for comparable performances, a system which uses
water/ice as the PCM often requires a second refrigeration cycle
unit and components such as a universal refrigerant management
system ("URMV") not needed by the present system 10 which utilizes
a PCM having low temperature wax and graphite and/or aluminum
oxide.
[0055] PCMs can also be any organic material, inorganic materials
like salt hydrates, bio-based materials like fatty acids derived
from plant and animal sources.
[0056] The TES unit 20 also is comprised of an insulating apparatus
23 that insulates the PCM 21 and the refrigerant coil 22. The
insulating apparatus 23 prevents thermal energy dispersion. The
material of the insulating apparatus 23 could be any material
commonly known in the art to thermally insulate such as, but not
limited to, polyurethane, fiberglass, and wood.
[0057] In use, the refrigerant 1 is pumped through the refrigerant
coil 22 in thermal communication with the PCM 21 thus lending its
cold thermal energy to the PCM 21, solidifying the same. The
refrigerant 1 exits the TES unit 20 via the outlet 25 of the
refrigerant coil 22 and enters the refrigeration cycle 30 via a
liquid pump 2 through the refrigerant management system. In this
way, the refrigerant 1 can again be made cold for ultimately
charging the PCM 21.
[0058] It should be noted that the refrigerant coil need not exist
in the TES unit 20 as a serpentine coil. Any shape or disposition
is acceptable as long as the refrigerant 1 remains in thermal
communication with the PCM 21. However, a serpentine coil shape of
the refrigerant coil 22 provides ample surface area along which the
refrigerant passes by or through the PCM providing good thermal
energy transfer to the PCM. The refrigeration coil 22 could be any
material known in the art to facilitate heat exchange. Some
examples of materials which could be used include, but are not
limited to, copper, copper alloys, aluminum, silver, gold, and
alloys of the same. On the other hand, the tubes of the refrigerant
management system should be covered with an insulating material
known in the art to insulate from heat dissipation so that transfer
of the refrigerant between the various components of the system
does not disperse thermal energy. Some examples of insulating
material which could be used include, but are not limited to,
polyurethane, fiberglass and polyethylene. The TES unit 20 can, in
other words, represents a heat exchanger with a serpentine of
internal refrigerant coils 22 where the liquid refrigerant 1 runs
through and cools the PCM 21 surrounding the coils. One of the
possible configurations of the TES unit 20 can be very similar to a
plate heat exchanger, composed of thin plates with a sufficiently
large surface to allow an effective thermal communication. This is
also true for all embodiments wherein a thermal energy storage unit
is used. (FIG. 1-4, FIG. 6 and FIG. 9-10).
[0059] The ventilation system 50 is composed of an air inlet 51 and
an air outlet 52. The air inlet 51 is adjacent to the PCM 21 of the
TES unit 20. In this way, the air inlet 51 transports warm
environmental air to the TES unit 20 and is configured to put the
warm air in thermal communication with the PCM 21. Therefore, it is
more optimal, but not necessary, for the air to be transported
between the material of the insulating apparatus 23 and the PCM 21
of the TES system 20. In operation, the warm air is transported
through the air inlet 51 past or through the PCM 21 of the TES unit
20. The PCM 21 is charged and therefore in a solid state and is
able to release cold thermal energy to the air. Opposite to the air
inlet 51, and adjacent the TES unit 20, resides the air outlet 52,
which in use transports the cooled air to a building's environment,
thus cooling the air of the building.
[0060] Any ventilation system which could be considered to operate
in a commonly used air conditioning system for a building can be
used in the invention. The ventilation system 50 can include, but
is not limited to, a propulsion device 19 for moving the air
through the air inlet 51 to and through the air outlet 52. The
propulsion device 19 can for example be a fan.
[0061] The system 10 also includes a thermal control system 40. The
thermal control system 40 can be manually monitored and governed,
whereby the system is turned on and off manually; can be
automatically controlled, whereby the system is set on a timer 41
according to parameters chosen and set as desired, for example
depending on past history of energy usage, to heat recordings, to
day versus night time usage, and peak demands; and can be monitored
by sensors providing real time temperature readings of the building
environment 45 and/or the PCM/PPC temperatures 43, and adjusting
the operation of the system 10 according to threshold levels set in
the control system. The thermal control system 40 can also be
connected to a network system whereby the thermal control system 40
can adjust the operation of the system 10 according to weather
forecasts or historical data. The thermal control system 40 can
also be provided with an override to an automatic or programmable
thermal control system 40 whereby manual override is implemented
for emergencies.
[0062] FIG. 2 illustrates another embodiment of the system 10. The
system 10 of FIG. 2 provides a refrigeration cycle 30 with a liquid
pump 2, a compressor 11, a condenser 12, an expansion valve 13, a
TES unit 20, a ventilation system 50, and a thermal control system
40. In this embodiment the TES unit presents a PCM 21 in thermal
communication with a refrigerant coil 22, and an insulating
apparatus 23 to avoid thermal dispersion and keep the TES thermally
insulated. The refrigerant 1 enters the refrigerant coil 22 through
the inlet 24 and exits from the outlet 25. In this particular
embodiment, the refrigeration cycle 30 also includes an evaporator
14 that completes the refrigeration cycle. In addition, the system
10 further is provided with a first valve 5 between the TES unit 20
and the expansion valve 13 of the refrigeration cycle 30 and a
second valve 6 located between the evaporator 14 and the TES 20. If
in use, the first valve 5 is closed and the second valve 6 is open,
then the TES unit 20 is bypassed by the refrigerant 1 thus allowing
for only using the refrigeration cycle 30, which in this case would
operate as purely an air conditioning system. In this particular
embodiment illustrated in FIG. 2, however, a liquid pump is
disposed between the second valve 6 and the compressor 11 of the
refrigeration cycle 30. By closing the second valve 6 and keeping
the first valve 5 open during operation, the evaporator 14 is
bypassed and the refrigerant 1 travels through the refrigeration
cycle 30 and the refrigerant management system's tubes 3 to the PCM
21 of the TES unit 20.
[0063] The first 5 and second 6 valves are open and closed
alternatively. The first and second valves 5, 6 can be any valve
commonly used or known in the art to stop or allow the flow of
refrigerant when in an open or closed position, for example a check
valve such as a solenoid valve or a ball valve could be used. When
the first valve 5 is open and the second valve 6 is closed the TES
unit 20 is charging; on the contrary, when the first valve 5 is
closed and the second valve 6 is open the TES unit 20 is bypassed
and the system functions as a traditional air conditioning loop as
described as follows: the refrigerant fluid 1 reaches the
compressor 11 as a low pressure gas. After being compressed the
refrigerant moves to the condenser 12 as a high-pressure gas. The
refrigerant gas condenses to a liquid state and releases its heat
to the outside environment. The high-pressure liquid refrigerant
then moves to the expansion valve 13 that lowers its pressure. The
low pressure liquid then moves to the evaporator 14 where the heat
from the outside air directed to the evaporator by means of a
ventilation system 50 is absorbed by the refrigerant, which goes
back to a low pressure gas state and moves to the compressor where
the refrigeration cycle is concluded. Traditionally, for an air
conditioning refrigeration cycle described in this paragraph the
refrigerant must be used continuously. This means that the liquid
pump 2 must operate repeatedly, resulting in a large amount of
electricity needed, although the work of the compressor could be
enough to guarantee sufficient transfer of refrigerant 1 throughout
the system. The liquid pump 2 can assist the compressor 11 if a
consistent transfer energy is required but its use could be
redundant in some cases. This invention also provides an embodiment
which uses the refrigeration cycle 30 and the liquid pump 2 only
during the TES 20 charging phase. While discharging, refrigerant
circulation is not necessary; a building can be cooled with only
the ventilation system 50 moving hot air past the PCM 21 or past
the evaporator 14.
[0064] Also provided in this embodiment, is an evaporator 14 which
allows for the refrigerant 1 in the refrigeration cycle 30, if used
alone bypassing the TES unit 20, to cool air directed by the inlet
51 across the evaporator 14 of the ventilation system 50. The
evaporator 14 could also serve to further cool air which has
already traveled through the ventilation system 50 across the
charged PCM 21 of the TES system 20. The ventilation system 50 can
be provided with a propeller like a fan 19 to be able to transfer
the air throughout the different cooling stages. Through the outlet
52 of the ventilation system 50, the air cooled by the PCM 21 can
be further cooled passing by the evaporator 14. The use of the
refrigeration cycle 30 and an evaporator 14 therein can provide
additional cooling down at least another 5.degree. Celsius. With
the use of the evaporator 14 as an extra cooler for the air coming
from the outlet 52, the ventilation system 50 will be able to
provide cold air to the environment through a second outlet 53.
[0065] The thermal control system 40 can operate in the same manner
as discussed above with the additional feature of allowing for
control of the first and second valves 5 and 6. The thermal control
system 40 can include a timer 41 and temperature sensors 43 located
in thermal contact with the PCM 21 and with the building
environment or space that needs cooling.
[0066] If the refrigerant 1 is water/glycol a chiller will take the
place of the condenser in the same position along the loop. Also an
expansion valve might not be required or bypassed if water/glycol
is used. If Freon is used as refrigerant 1 the liquid pump will not
be required.
[0067] FIG. 3 is yet another embodiment of the system 10 of the
present invention, wherein provided is a refrigeration cycle 30, a
TES unit 20, an external TES unit 80, a ventilation system 50, an
external ventilation system 60 and a thermal control system 40. The
refrigeration cycle 30 also comprises a compressor 11, a condenser
12 and an expansion valve 13. The embodiment illustrated in FIG. 3
also includes a third valve 7 located between the TES 20 and the
first valve 5. In this embodiment, there is shown an external
refrigerant coil 27, external to the TES unit 20. In addition, heat
exchange can take place in a heat exchanger wherein the air and the
refrigerant exchange heat. In another embodiment, there could be a
plurality of external refrigerant coils 27, some of which can be
part of each of a plurality of external TES unit(s) 80, each also
having a PCM 81.
[0068] Moreover, this embodiment can also include an external
ventilation system 60, which is configured to put warm air from
another location of the same building into thermal communication
with the external refrigerant coils 27 and PCM 81. The ventilation
system 50 can be provided with a fan 19 or any equivalent air
propeller capable of directing warm air from an area of the
building through the PCM 21 of the TES 20. This air can enter the
ventilation system 50 through the inlet 51 and exit from the outlet
52. The external ventilation system 60 can also be provided with a
propeller 65. The warm air can enter the external ventilation
system 60 in the external ventilation system inlet 61 and exit from
the external ventilation system outlet 62. In this embodiment the
liquid pump 2 is located between the TES 20 and the external TES 80
and is configured to pump cold refrigerant from the TES 20 to cool
the PCM 81 in the external TES 80. The TES 20 includes the
refrigerant coil 22 having an inlet 24 and an outlet 25. In use,
the liquid pump 2 of the system 10 pumps the refrigerant 1 through
the refrigerant coil 22 so that the refrigerant is in thermal
communication with the PCM 21. Moreover, the TES 20 is thermally
insulated by means of an insulating apparatus 23.
[0069] In this embodiment, the PCM 21 of the TES unit 20 is charged
via the cold refrigerant 1, which runs through the tubes 3 of the
refrigerant management system, which exits the expansion valve 13
of the refrigeration cycle 30. To charge the TES 20 the third valve
7 and the second valve 6 are open while the first valve 5 is
closed. In this way the TES 80 is bypassed. Contrariwise, it is
possible to charge the TES 80 bypassing the TES 20 closing the
third valve 7 while the first valve 5 and the second valve 6 are
open. In use, when the second valve 6 and the expansion valve 13
are closed, while the first valve 5 and the third valve 7 are open,
the refrigerant 1 can utilize the charged PCM 21 of the TES unit 20
to deliver cool thermal energy to the external refrigerant coil 27
and charge the PCM 81. The external TES 80 could also be equipped
with an external insulating device 29, which would prevent
dispersion of thermal energy. The refrigerant 1 can enter the
external refrigerant coil 27 from the inlet 84 and exit from the
outlet 85. In this way, there can be more than one ventilation
system designated to cool different areas of the same building,
using the same refrigeration cycle 30, wherein the first
ventilation system 50 resides in thermal communication with only
the PCM 21 of the TES unit 20, and air passing through an external
ventilation system 60 can be cooled by thermally communicating with
the TES 80, which includes external refrigeration coil 27 and PCM
81. It is also possible that there is yet another embodiment that
illustrates a plurality of both external refrigeration coils 27 and
also external TES units 80. For such a system 10, it may be
desirable to implement the same with a plurality of liquid pumps
2.
[0070] In this embodiment, the first valve 5 is disposed between
the expansion valve 13 and the external refrigerant coil 27. The
second valve 6 is located between the liquid pump 2 and the
compressor 11. The thermal control system 40 can include, but is
not limited to, such features as a timer 41 functioning as
described in FIG. 1 but related to the TES 20, a timer 49
associated with the TES 80, a PCM temperature sensor 43 for PCM 21,
a PCM temperature sensor 83 for PCM 81, an environment temperature
sensor 45 for a first environment of the building and another
environment temperature sensor 47 for a second environment of the
same building.
[0071] FIG. 4 also shows an embodiment of the system 10 in
accordance with the principles of this invention and a refrigerant
1 running through a system of tubes 3 of the refrigerant management
system that connects the components of the different loops. The
embodiment in FIG. 4 has a refrigeration cycle 30 with a liquid
pump 7, a compressor 11, a condenser 12, and an expansion valve 13
functioning in a manner equivalent to the previous embodiments, a
TES unit 20, a second TES 80 with PCM 81, external refrigerant coil
27 and an insulating apparatus 29, a ventilation system 50, a
second ventilation system 60 and a thermal control system 40.
[0072] In this embodiment is also provided an evaporator 14 for the
refrigeration cycle 30 which allows the system 10 to potentially
run exclusively as an air conditioning refrigeration unit, but in
addition, depending on the placement of the evaporator 14 in
relation to the primary ventilation system 50 and the external
ventilation system 60, the evaporator 14 could serve to further
chill air running through the primary 50, external ventilation
system 60, or both i.e. across the TES unit 20 and/or 80 and then
the evaporator, down a few more degrees than possible only with the
TES unit 20.
[0073] Moreover, this embodiment presents a second liquid pump 7 in
addition to the liquid pump 2, a third valve 8 and a fourth
solenoid valve 9 in addition to the first solenoid valve 5 and the
second solenoid valve 6. The liquid pump 2 is placed between the
TES 20 and the TES 80; the liquid pump 7 is located between the
evaporator 14 and the compressor 11; the first solenoid valve 5 is
between the TES 80 and the fourth solenoid valve 9, while the
second solenoid valve 6 is placed between the liquid pumps 2 and 7.
The third solenoid valve 8 is between the evaporator 14 and the
expansion valve 13; the fourth solenoid valve 9 is between the
expansion valve 13 and the TES 20.
[0074] In this embodiment is shown an external refrigeration coil
27, and thus the system 10, is configured to charge the PCM 21 of
the TES unit 20, and then to operate in a discharge mode while
keeping environmental air cool. The thermal control system 40 can
include a timer 41, associated to the first ventilation system 50
and the first TES unit 20, functioning as described in FIG. 1,
another timer 49 associated to the second ventilation system 60 and
the second TES unit 80, a PCM temperature sensor 43 for PCM 21, a
PCM temperature sensor 83 for PCM 81, an environment temperature
sensor 45 for a first environment of the building and another
environment temperature sensor 47 for a second environment of the
same building.
[0075] This particular embodiment can be used as a 2-stage cooling
system for air coming from 2 distinct areas of the same building,
therefore using the same refrigeration cycle 30, but with 2
separated ventilation systems (50 and 60) and TES units (20 and
80).
[0076] The ventilation system 50 has warm air pushed from a
building environment through the inlet 51 by means of a fan 19 or
any equivalent ventilation propeller towards the PCM 21. The air
exiting the PCM 21 (and the TES unit 20) is cooled at the exit
section 52 of the ventilation system. If directed through the
evaporator 14, the air from the TES 20 is further cooled at the
outlet section 53.
[0077] The ventilation system 60 has warm air pushed from a
building environment through the inlet 61 by means of a fan 65 or
any equivalent ventilation propeller towards the PCM 81. The air
exiting the PCM 81 (and the external TES unit 80) is cooled at the
exit section 62 of the ventilation system. If directed through the
evaporator 14, the air from the external TES unit 80 is further
cooled at the outlet section 63.
[0078] In the TES 20 the refrigerant 1 coming from the refrigerant
management system's tubes 3 is put in thermal communication with
the PCM 21 when entering the refrigerant coil 22 from the inlet 24.
The refrigerant 1 exits the PCM 21 from the outlet 25. An
insulating apparatus 23 limits thermal loss and dispersion to the
surrounding environment. Similarly, in the TES unit 80 the
refrigerant 1 is put in thermal communication with the PCM 81
entering the inlet 84 to the external refrigerant coil 27. The
refrigerant 1 thereafter goes back to the refrigerant management
system exiting the outlet 85.
[0079] In the embodiment represented in FIG. 4 the system 10 can
function as a traditional air conditioning system when the valves
6, 9 and 5 are closed, and the valve 8 and the expansion valve 13
are open. In this way the TES units 20 and 80 are isolated. Warm
air from the building can be cooled only through the evaporator 14
if one of the ventilation systems 50 and 60, or both, are in use.
The PCM 21 can be charged and solidify with the refrigeration cycle
30 in use and valves 5 and 8 are closed, while valves 6 and 9 are
open. The PCM 81 can be charged when the refrigeration cycle 30 is
in use, with valves 8 and 9 closed and valves 5 and 6 open.
[0080] It is also possible to charge the PCM 81 with the cold
refrigerant 1 coming from the TES unit 20, thus with the
refrigeration cycle 30 not in use. To achieve this, liquid pump 2
is operational, while liquid pump 7 is not; for this operation the
valves 5 and 9 are open while valves 8, 6 and the expansion valve
13 are closed.
[0081] During discharge mode, the ventilation systems 50 and 60 can
be in use alternatively or at the same time, depending on the
cooling requirement of the environment.
[0082] FIG. 5 illustrates a TES unit having the PCC configured as a
slab. This could be a possible configuration of a TES unit 20 (or
80) illustrated and discussed in reference to the previous figures.
The PCM 21 is shown in a single slab design with the refrigerant
coil 22 running though the slab in the shape of a serpentine
disposed longitudinally across the PCM 21 slab, with an ample area
covered for effective thermal transfer between the refrigerant 1,
coming from the refrigerant management system's tubes 3, and the
PCM 21. The PCM 21 can be designed to be in many different
configurations including, but not limited to, a plurality of PCM 21
slabs stocked in piles, or other convenient geometrical shapes
implemented with the same concept illustrated in FIG. 5. The
refrigerant 1 is pumped by means of the pump 2, or other pumps
installed in the refrigerant loop 30, in the refrigerant coil 22;
the refrigerant 1 enters the refrigerant coil 22 through the inlet
24 from the management system tubes 3 and exits the refrigerant
coil 22 from the outlet 25.
[0083] An insulating apparatus 23 surrounds the PCM 21 and the
refrigerant coil 22 to guarantee thermal insulation and avoid the
loss of thermal energy to the surrounding environment.
[0084] Also provided is a temperature sensor 43 in thermal
communication with the PCM 21 which can be operationally connected
with the control system 40 to provide information about the
temperature of the PCM material. For instance, when the PCM
temperature reaches an established threshold, the control system 40
could start the refrigeration cycle 30 to initiate the charging
process of the PCM 21.
[0085] The PCM 21 and refrigerant coil 22 configuration proposed in
FIG. 5 can be adapted for TES solutions in all the 4 embodiments
illustrated in FIGS. 1-4 and can be suitable for TES unit 20 as
well as TES unit 80.
[0086] FIG. 6 is yet another embodiment of the system 10 of the
present invention, wherein provided is a refrigeration cycle 30, a
TES unit 20, an external ventilation system 60 and a thermal
control system 40. The refrigeration cycle 30 also comprises a
compressor 11, a condenser 12 and an expansion valve 13. The
embodiment illustrated in FIG. 6 also includes a third valve 7
located between the TES 20 and the expansion valve 13. In this
embodiment, there is shown an external refrigerant coil 27,
external to the TES unit 20. In another embodiment, there could be
a plurality of external refrigerant coils 27.
[0087] This embodiment includes an external ventilation system 60,
which is configured to put warm air from another location of the
same building into thermal communication with the external
refrigerant coils 27 that cool the warm air with refrigerant 1
coming from the cold TES unit 20. The external ventilation system
60 can also be provided with a propeller 65. The warm air can enter
the external ventilation system 60 in the inlet 61 and exit from
the outlet 62. In this embodiment the liquid pump 2 is located
between the TES unit 20 and the external refrigerant coils 27 and
is configured to pump cold refrigerant 1 from the TES unit 20 to
cool the refrigerant coils 27, when the second valve 6 is closed.
The TES unit 20 includes the refrigerant coil 22 having an inlet 24
and an outlet 25. In use, the liquid pump 2 of the system 10 pumps
the refrigerant 1 through the refrigerant coil 22 so that the
refrigerant is in thermal communication with the PCC 21. Moreover,
the TES unit 20 is thermally insulated by means of an insulating
apparatus 23.
[0088] In this embodiment, the PCC 21 of the TES unit 20 is charged
via the cold refrigerant 1, which runs through the tubes 3 of the
refrigerant management system, which exits the expansion valve 13
of the refrigeration cycle 30. To charge the TES unit 20 the third
valve 7 and the second valve 6 are open while the first valve 5 is
closed. In this way the refrigerant coils 27 are bypassed. It is
also possible to cool the refrigerant coils 27 bypassing the TES
unit 20 closing the third valve 7 while the first valve 5 and the
second valve 6 are open. In use, when the second valve 6 and the
expansion valve 13 are closed, while the first valve 5 and the
third valve 7 are open, the refrigerant 1 can utilize the charged
PCM 21 of the TES unit 20 to deliver cool thermal energy to the
external refrigerant coil 27 and cool the warm air directed by the
ventilation system 60 in thermal communication with the refrigerant
coils 27 and back to the building environment through the outlet
62. The refrigerant 1 can enter the external refrigerant coil 27
from the inlet 84 and exit from the outlet 85.
[0089] In this embodiment, the first valve 5 is disposed between
the expansion valve 13 and the external refrigerant coil 27. The
second valve 6 is located between the liquid pump 2 and the
compressor 11. The thermal control system 40 can include, but is
not limited to, such features as a timer 41 functioning as
described in FIG. 1 but related to the TES unit 20, a PCM
temperature sensor 43 for PCM 21, a PCM temperature sensor 83 for
the refrigerant coils 27 and an environment temperature sensor 47
for measuring the temperature of the air in the building.
[0090] In this embodiment, the region of the system where thermal
exchange between the refrigerant 1 and the warm air from the
environment takes place can also be thought or represented by a
typical heat exchanger for air conditioning applications where
internal coils (in this case our external refrigerant coils 27)
have refrigerant running therethrough. This heat exchanger can be
designed in order to have the largest heat exchange surface
possible, with as many indentations or fins as possible in order to
allow water molecules to remain in the cooled air.
[0091] FIGS. 7 and 8 respectively illustrate the front and rear
view in perspective of an embodiment of the TES unit 20 which has
twenty eight (28) PCC slabs (101-128) of comparable dimensions,
arranged in a pile and the refrigerant coil 22 running between the
slabs. The embodiment shown in FIGS. 7 and 8 can be enclosed in the
insulating apparatus 23 of the TES unit 20 and/or in the insulating
apparatus 29 of the TES unit 80. The refrigerant 1, after running
through the tubes 3 of the refrigerant management system pours into
the refrigerant coil 22 from the inlet 24. 101 is the first slab
from the bottom, 105 is the fifth slab from the bottom, 110 is the
tenth slab from the bottom and so on; 128 is slab on top of the
pile. As shown in the FIG. 7, in this embodiment of the TES unit
20, after the inlet 24, the refrigerant coil 22 penetrates between
the PCC slabs from the left side of the front section, splitting
into 3 conduit tubes that run from the front section to the rear
section in parallel, one over the other, between slabs 128 and 127,
between slabs 127 and 126 and between slabs 126 and 125. After
exiting the PCC slabs from the rear section the parallel tubes of
the refrigerant coil 22 go back towards the center of the rear
section between the same slabs and exit from the front section.
Again the parallel tubes go back to the rear section and come back
to the front section. In total, after splitting into 3 tubes, the
refrigerant coil 22 runs through each couple of PCC slabs with 4
tubes segments, maximizing the thermal communication between the
PCM material 21 and the refrigerant 1.
[0092] The 3 parallel tubes exiting one last time from the PCC
slabs from the front section on its right side curve towards the
lower layers of slabs and penetrate in parallel between slabs 125
and 124, 124 and 123, 123 and 122 on the right side of the front
section. Again, the tubes run back and forth from the front to the
rear and from the rear to the front section in parallel between the
same slabs twice and exit the front section on its left side before
moving to the lower slabs (between 122 and 121, between 120 and 119
and between 119 and 118) and repeating the same procedure until
reaching the last 4 slabs placed at the bottom of the TES unit 20.
The 3 parallel tubes run through the PCC slabs between slabs 4 and
3, slabs 3 and 2 and slabs 2 and 1 from left to right back and
forth 4 times and merge in a single tube refrigerant coil in the
bottom-right area of the front section of the PCC slabs pile. The
refrigerant 1 exits the refrigerant coil 22 at the outlet 25. From
the outlet 25, the refrigerant 1 flows into the tubes 3 of the
refrigerant management system.
[0093] The design described above and illustrated in FIGS. 7 and 8
can have, but is not limited to, a PCM phase change temperature of
between about 5.degree. C. to about 6.degree. C., PCC latent heat
of about 180 KJ/Kg and PCC density of about 850 Kg/m.sup.3. In one
cooling experiment, 28 slabs were piled one over the other with the
TES unit 21 comprising 74% PCC and 11.5% copper tubing for the
refrigerant coil 22. The remaining percentage is mainly the
insulating apparatus and sensors. Other characterizing features of
this embodiment of a TES unit 20 could be, but are not limited to,
a thermal capacity of about 4.2 kWh, PCC's energy density of about
54 Wh/Kg, PCC and copper refrigerant coil 22 energy density of
about 46 Wh/Kg and system energy density of about 40 Wh/Kg.
[0094] Several discharge experiments have been conducted at
different refrigerant flow rates. For example, at 1.6 L/min a total
cooling time of more than 6 hours was achieved with cold
refrigerant reaching the external refrigerant coil 27 for the whole
period, while the refrigerant flowing through the different slabs
was heating up at different rates: less than 1 hour for the
refrigerant at the inlet (slab 128 to 125), 3 to 4 hours at slabs
115 and 119, 104, to 105 hours at slab 123, 5 to 6 hours at slab
107 and 6.25 hours from slabs 104 to 101.
[0095] FIG. 9 represent an embodiment of the present invention
wherein water/glycol used as the refrigerant 1. The only difference
from the previous embodiments is the substitution of the condenser
12 with an electronically controlled chiller 18 and no expansion
valve is used in the system.
[0096] FIG. 10 represents an embodiment of the present invention
wherein the refrigerant 1 is Freon.TM.. In this embodiment, a
liquid pump is not required.
[0097] As to the manner of usage and operation of the present
invention, the same should be apparent from the above description.
Accordingly, no further discussion relating to the manner of usage
and operation will be provided.
[0098] While a preferred embodiment of the system has been
described in detail, it should be apparent that modifications and
variations thereto are possible, all of which fall within the true
spirit and scope of the invention. With respect to the above
description then, it is to be realized that the optimum dimensional
relationships for the parts of the invention, to include variations
in size, materials, shape, form, function and manner of operation,
assembly and use, are deemed readily apparent to one skilled in the
art, and all equivalent relationships to those illustrated in the
drawings and described in the specification are intended to be
encompassed by the present invention.
[0099] Throughout this specification, unless the context requires
otherwise, the word "comprise" or variations such as "comprises" or
"comprising" or the term "includes" or variations, thereof, or the
term "having" or variations thereof will be understood to imply the
inclusion of a stated element or integer or group of elements or
integers but not the exclusion of any other element or integer or
group of elements or integers. In this regard, in construing the
claim scope, an embodiment where one or more features is added to
any of the claims is to be regarded as within the scope of the
invention given that the essential features of the invention as
claimed are included in such an embodiment.
[0100] Those skilled in the art will appreciate that the invention
described herein is susceptible to variations and modifications
other than those specifically described. It is to be understood
that the invention includes all such variations and modifications
that fall within its spirit and scope. The invention also includes
all of the steps, features, compositions and compounds referred to
or indicated in this specification, individually or collectively,
and any and all combinations of any two or more of said steps or
features.
[0101] Therefore, the foregoing is considered as illustrative only
of the principles of the invention. Further, since numerous
modifications and changes will readily occur to those skilled in
the art, it is not desired to limit the invention to the exact
construction and operation shown and described, and accordingly,
all suitable modifications and equivalents may be resorted to,
falling within the scope of the invention.
* * * * *