Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
P1216-1 CA
1
COLD GENERATION AND STORAGE
FIELD OF THE INVENTION
[0001] The invention relates to the field of thermal energy storage in
general, and to
cold generation and storage in particular.
BACKGROUND
[0002] Thermal energy storage (TES) allows thermal energy to be stored and
used
io hours, days or months later, at scales ranging from the individual
consumer, a building,
a multiuser-building, a district, a town, a region, or the like.
[0003] Usage examples include balancing of energy demand between different
hours,
such that hot or cold are produced and stored during low electricity rate
hours, and used
on higher rate hours. Other uses, referred to as seasonal thermal energy
storage include
is storing summer heat for winter heating, or winter cold for summer air
conditioning.
[0004] TES may be achieved with widely differing technologies. For example,
hot
storage media include masses of native earth or bedrock accessed with heat
exchangers
by means of boreholes, deep aquifers contained between impermeable strata;
shallow,
lined pits filled with gravel and water and insulated at the top; eutectic
solutions
20 and phase-change materials, or others.
[0005] Other sources of thermal energy for storage include heat produced with
heat
pumps from off-peak, lower cost electric power, a practice called peak
shaving; heat
from combined heat and power (CHP) power plants; heat produced by renewable
electrical energy that exceeds grid demand and waste heat from industrial
processes.
25 [0006] Cold storage media may include collecting cold water or ice
tanks. When
needed, water or another fluid can be streamed through or near the water or
ice, cooled
and used in cooling systems.
[0007] Heat and cold storage, both short term (e.g. hours) and seasonal, is
considered
an important means for cheaply using variable renewable energy sources, for
purposes
30 of electricity production and integration of energy systems fed by
renewable energy.
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SUMMARY
[0008] The following embodiments and aspects thereof are described and
illustrated in
conjunction with systems, tools and methods which are meant to be exemplary
and
illustrative, not limiting in scope.
[0009] There is provided, in accordance with an embodiment a system for
generating
and storing cold, comprising: a storage container for storing cold water and
ice; and a
cooling unit comprising: a cooling element positioned within the storage
container,
designed for having cooling refrigerant streamed within; and an electrically-
insulating
io layer having electrically conductive coating, and having electrical
wiring laid over the
layer, wherein the layer is larger than a projection of the cooling element on
the layer
along a line perpendicular to the layer, the layer positioned such that the
cooling
element causes ice to form on the layer, wherein applying current to the
electrical
wiring causes the layer to heat, thereby enabling ice formed on the layer to
release and
is float towards the top of the storage container. Within the system, the
cooling unit can
further comprise a heat spreading member, the heat spreading member positioned
between the cooling element and the layer. The system can further comprise a
second
electrically insulating layer having an electrically conductive coating, such
that the
cooling element is positioned between the layer and the second layer. Within
the
20 system, the cooling unit can further comprise a second heat spreading
member, the
second heat spreading member positioned adjacent to the second layer. Within
the
system, the layer is optionally made of Kapton0 RS. Within the system, the
second
layer is optionally made of Kapton0 RS. Within the system, the layer
optionally has
thickness of at most 100 m. The system can further comprise a controllable
switch for
25 closing a circuit such that current is applied to the electrical wiring.
The system can
further comprise: a sensor for capturing at least one aspect of ice formed on
the first
layer and provide output; and a processor configured to analyze the output of
the sensor
and determine a time for applying current to the electrical wiring.
[0010] In addition to the exemplary aspects and embodiments described above,
further
30 aspects and embodiments will become apparent by reference to the figures
and by study
of the following detailed description.
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BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Exemplary embodiments are illustrated in referenced figures. Dimensions
of
components and features shown in the figures are generally chosen for
convenience and
clarity of presentation and are not necessarily shown to scale. The figures
are listed
below.
[0012] Fig. 1A is a perspective view of an ice forming and storing container,
in
accordance with some exemplary embodiments of the disclosure;
[0013] Fig. 1B is a front view of the ice forming and storing container of
Fig. 1A, in
accordance with some exemplary embodiments of the disclosure;
to [0014] Fig. 2A is an illustration of a cooling unit, in accordance with
some exemplary
embodiments of the disclosure;
[0015] Fig. 2B is a top view of the cooling unit, in accordance with some
exemplary
embodiments of the disclosure;
[0016] Fig. 2C is an illustration of a heat spreading plate, in accordance
with some
exemplary embodiments of the disclosure;
[0017] Fig. 2D is an illustration of an electrically resistive layer and
electrical wires
laid thereon, in accordance with some exemplary embodiments of the disclosure;
[0018] Fig. 3A is an illustration of a flat layer, electrical wires laid
thereon, and
formed ice cap, in accordance with some exemplary embodiments of the
disclosure;
[0019] Fig. 3B is a top view of the cooling unit and formed ice caps, in
accordance
with some exemplary embodiments of the disclosure; and
[0020] Fig. 4 is a flowchart of a steps in a method for creating and storing
cold, in
accordance with some embodiments of the disclosure.
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DETAILED DESCRIPTION
[0021] The disclosure relates to a system and a method for generating and
storing
cold, and using the same for cooling applications such as air-conditioning and
refrigeration.
[0022] Known solutions exist for cold generation and storage. Some of the
solutions
include the generation of ice blocks or chunks, such that at a later time
water or another
fluid can be streamed next to the ice, cooled, and used for cooling
applications.
[0023] Some common reasons for storing cold thermal energy include shifting
the
demand for electricity from the high rate peak demand hours to low demand, low
rate
hours. This enables a user to enjoy cooling on the higher rated hours, while
avoiding the
relevant charges of these hours and paying lower-rated electricity charges on
other
hours. The charges may be measured, for example, in $/kWh.
[0024] Another common reason for storing cold thermal energy is the aim to
utilize
the availability of renewable green energy sources such as sun and wind, by
using
photovoltaic solar cells and wind turbines. However, such sources are usually
available
only part of the time. For example, photovoltaic solar cells may be used only
in
daylight, and wind turbines are effective only when the wind blows. By storing
thermal
energy, the energy produced by such sources may be put to use also when the
source
itself is unavailable, thereby reducing usage of non-renewable polluting
energy sources.
This is true for "stand alone" or local energy production, as well as for
electricity from
the electricity grid, where the thermal storage is activated by relevant
signals from the
grid ("smart grid").
[0025] Thus, producing ice when possible or when the rates are low, and using
it for
cooling at other times, can save energy or money. For example, ice (water)
based cold
thermal energy storage may make use of the water 334J/g solid-to-fluid latent
heat
capacity. Thus, one metric ton of ice, composed of plain tap water, can store
about
93KWh of cooling thermal energy.
[0026] Some cold storage systems include components for standard refrigeration
cycle, including a compressor, a condenser, a metering device (typically an
orifice, an
expansion valve or a capillary tube) and an evaporator. The refrigeration
system may
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further comprise a thermally insulated tank for storing water or ice, the tank
having
therein a cooling element submerged in water. In some embodiments, the
evaporator is
the cooling element, also referred to as a cooling plate.
[0027] The cooling element is used to cool the fluid water in the insulated
tank, and to
5 freeze it once the water reaches a temperature near zero degrees Celsius,
thus a layer of
ice is formed on the cooling element.
[0028] The ice formed on the cooling element has poor heat conductivity, in
accordance with the following formula for conductive heat transfer:
, *A
(Eq. 1) q = K *At
-
L
wherein q is the heat flow rate; k is a constant; At is the temperature
difference between
the cooling element and the water temperature; A is the surface area of the
cooling
element; and L is the thickness of the ice layer separating the cooling
element and the
water. Thus, as the layer of ice thickens, the heat flow rate through the ice
is reduced
and the ice formation process slows down.
[0029] For example, using solar panels during sun hours, converting one metric
ton of
fluid water into solid ice in seven hours requires an average cooling rate of
13.3KW.
[0030] In the above example, using a 1 square meter flat cold element and
applying
the heat transfer equation, achieving a cooling power of 13.3 KW after the
formation of
lOmm ice thick layer over the 1 square meter flat cold element will require a
temperature gradient (At) of 60.5 C between the cold element on one side and
the fluid
water on the other side of the ice layer, which may be impractical. Increasing
the ice
thickness, for example letting the ice layer to become 11 mm thick, will
increase the
temperature gradient At at the same proportion, i.e. to over 66 C which may be
even
less practical. It will be appreciated that the cooling power is equivalent to
the heat flow
rate: in a tank full of water, once ice started forming, it can be
theoretically assumed
that all the cooling power is used to freeze additional water. Practically,
the ice layer
between the cooling element and the water also cools down to sub-zero
temperatures,
which slows down further ice creation. A similar phenomenon can be seen in
domestic
refrigerators: when freezing water into ice cubes, the water cools to zero
relatively fast,
causing the creation of a thin layer of ice on the top of each cube. However,
it takes
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additional significant time until the full volume of water freezes into ice
cubes. The
example above thus demonstrates that there is a need for a huge temperature
gradient in
order to achieve reasonable ice creation rate. Obtaining such low evaporating
temperatures requires the usage of expensive refrigeration systems that may
make the
entire solution un economical.
[0031] As can also be seen from Eq. 1 above, having a cooling element with a
large
surface area, for example a cooling element with multiple curvatures, provides
for fast
initial ice formation. However, as the ice forms, the gaps between the bends
fill with
ice, thus reducing the surface area A, which again slows the ice formation.
io Alternatively, a very large cooling element may be used, but is also
more expensive.
[0032] Thus, one technical problem of the disclosed subject matter is the need
to
periodically release the ice formed on or near the cooling element, and let
the ice float
towards the top of the tank. This will enable further ice formation to be more
efficient,
such that larger quantities of ice can be formed over time and used when
needed.
is Releasing the ice may be challenging, since if the ice sticks to the
cooling element even
at a very small area, or a bend or another geometrical limitation prevents a
part of the
ice from floating, the whole block of ice will remain stuck to the cooling
element and
will not float, thus again slowing down the cooling process. Therefore, such
cases
should be avoided.
20 [0033] It will be appreciated that gradual heating of the cooling
element, as may
happen where heating is done by streaming hot fluid through the cooling
element,
causes areas of the ice that have already been released to be heated and melt
further,
until the last bit of ice-cooling element bond is melted.
[0034] Thus, another technical problem of the disclosed subject matter is the
need to
25 provide heat for melting the ice such that the ice can be released, in a
uniform manner
to avoid unnecessary melting of the ice.
[0035] One technical solution of the disclosure relates to a method and device
for cost
effective, cold thermal energy storage. The method and device are based on a
refrigeration cycle, composed of a compressor, a condenser, a metering device
30 (typically an expansion valve or capillary tube) and an evaporator. The
refrigeration
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system cools a cooling element that is part of a cooling unit submerged in
water, inside
a thermally insulated water tank. The cooling element cools the fluid water in
the
insulated tank, and once the water reaches near zero Celsius temperature, the
water
freezes. As detailed below, the ice is then released from the cooling unit and
collected
for later use.
[0036] In some embodiments, the evaporator is a heat spreader type evaporator,
which
may be the cooling element, optionally comprising also a heat spreading
member. The
cooling element may be formed, for example as one or more tubes or flattened
tubes, a
cylinder, rolled bonded plates, or any other shape, such that the refrigerant
is flowing
io within the cooling element and cools it. The shape of the cooling unit
is required to be
such that by melting the ice formed adjacent to the cooling unit, the ice will
be released
and free to float, and will not stick or be "hooked" to the cooling element.
[0037] In further embodiments, the evaporator is used for cooling a secondary
fluid,
typically water with antifreeze solution. The cooled solution is cooled to a
sub-zero
is Celsius temperature and is circulated between the evaporator and a
cooling element that
is submerged in the cooled water tank. Once the water in the storage tank is
cooled to
about zero Celsius the same water freezing process is commended.
[0038] In both embodiments, a cooling unit that includes the cooling element
may
comprise a thin layer of electrically resistive heat conductive material, or a
thin layer of
20 electrically resistive material having conductive coating applied
thereto. The coating
may be applied as paint, as another layer positioned attached to the
electrically resistant
layer, or the like. In some embodiments, the coating may be partial, for
example not
cover the whole layer but rather be laid in a pattern, for example warp and
woof stripes.
The layer or coating may have electrical wires laid thereon.
25 [0039] Once the water within the tank cools to near zero Celsius
degrees, for example
1-2 degrees, ice begins to form on the cooling unit including parts of the
electrically
resistive layer or the coating. As ice has poor heat conductivity, the thicker
the ice layer
is, the slower the ice formation process becomes. The cooling unit is designed
such that
after some ice is formed on the layer or coating, the electrically resistive
layer or
30 coating can be heated by supplying current to the electrical wires,
which causes some
ice to melt, such that the ice layer releases, allowing the ice to naturally
float to the top
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of the water tank. It will be appreciated that the electrically conductive
coating thus
serves as a resistive heater. If previous ice crystals or blocks are already
floating at the
top of the tank, the newly released ice layer floats as high as it can. Then,
the direct
contact of the layer or coating with the water is regained, and another ice
forming cycle
can start, thus achieving overall faster, energy efficient ice formation rate.
[0040] The cooling unit is designed such that when the cooling element is
active, at
least a certain amount of ice is formed on the layer before bonding with ice
formed
directly on the cooling element or on other parts of the cooling unit. This is
useful in
avoiding "hooking" of the ice over the cooling element. For this effect to be
achieved,
io the layer may be, for example, a flat film which extends beyond the
cooling element. In
other words, the layer may be larger than the projection of the cooling
element on the
layer. In some embodiments, since the layer is very thin, its edges may be
strengthened
by a rigid frame. The rigid frame may be made of heat insulating material
which will
not be cooled by the cooling element, such that ice will not form on the
frame, thus
is preventing the ice formed on the layer from bonding to ice formed on the
cooling
element.
[0041] In some embodiments, a heat spreading member made of thermal conductive
material may be positioned between the cooling element and the layer. For
example, the
heat spreading member may be designed to correspond to the structure of the
cooling
20 element on one side, such that the heat spreading member reduces the
amount of ice
that is formed on the cooling element, and to the electrically resistive layer
on the other
side. The layer may also be larger than the side of the heat spreading plate
attached
thereto.
[0042] In order to enable release of the ice formed on the layer, current may
be
25 applied to the wires. The current will cause the coating of the layer to
heat due to the
electric conductivity of the coating, thus releasing the ice formed thereon.
[0043] The layer may provide electric insulation between the coating and the
heat
spreading member or the cooling element which are generally made of
electrically
conductive material such as copper or aluminum, thus preventing a short-
circuit through
30 the heat spreading member or the cooling element. However, the layer may be
extremely thin, and thus makes only a minor disturbance to the heat flow from
the water
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to the cooling element. Due to the design, in which the layer is larger than
the cooling
element or the heat spreading layer attached thereto, the ice formed on the
layer is
easily released as it is separate from ice formed on parts of the cooling
element or the
heat spreading member that are in contact with the water.
[0044] The layer may be made of Kapton RS, which indeed comprises the
required
properties as detailed below.
[0045] 1. Due to its extreme thinness, such as 10-200 m, for example 50 m, it
does
not thermally insulate the cooling element from the water, thus causing
practically no
disturbance to the ice forming. However, even such thin layer of Kapton RS is
sturdy
i o and durable.
[0046] 2. Electrical insulation: since the cooling element may be made, for
example,
of copper or aluminum, it is a very good electrical conductor. Thus,
activating an
electrical heating system requires electrically insulating the cooling element
from the
heating element. If, for example, conductive paint would be applied directly
to the
is cooling element, the current would flow through the cooling element thus
creating a
short-circuit, without the heating element being heated. The Kapton RS thus
provides
the required electrical insulation between the cooling element and the
electrified area.
[0047] 3. By laying the electrical wires on two opposite ends of the coating,
once
current is applied to the wires, the coating becomes a very thin heating
element that
20 heats evenly, thus releasing the formed ice all over and allowing it to
float.
[0048] It will be appreciated that materials other than Kapton may also be
used, for
example silicone, rubber, PET plastic, or the like. However, in order to
provide the
required electric insulation, such materials may have to be thicker than
Kapton, thus
reducing the heat transfer between the water and the cooling element.
25 [0049] One technical effect of the disclosure is a fast and efficient
system and method
for cold generation and storage, that create significant amounts of ice which
can then be
used for cooling purposes at other times. The system and method are designed
to
periodically release ice formed in a container, such that further water can
make direct
contact with cold elements and form more ice. The formed and released ice
gathers at
30 the top of the container and is then ready for use. The specific
structure, including the
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thin electrically insulating layer positioned between the cooling element and
a heating
element, e.g. the coating, provides for effective release of the formed ice,
such that
further ice can be formed at high rate, wherein the thinness of the layer does
not disturb
the ice forming.
5 [0050] Another technical effect of the disclosure is that the system and
method can
use renewable resources for cooling when available for producing and storing
cold, and
using the stored cold when the resources are unavailable, thus using renewable
"green"
energy sources. Systems and devices in accordance with the disclosure may be
incorporated into smart grids in which the grid communicate with the device
and causes
10 it to start and stop.
[0051] The disclosure thus provides for generation and storage of cold in
hours during
which the full electricity generation facilities are not fully utilized, for
example during
night hours in hot countries. The cold can then be utilized during hours in
which the
demand is high, wherein said demand is currently supplied by polluting peaking
power
plants which emit excess carbon dioxide due to low energy efficiency.
Moreover, some
of these plants are highly polluting due to their usage of polluting
substances like mazut
or diesel fuel.
[0052] Referring now to Fig 1A, showing an exemplary embodiment of a
perspective
view of an ice forming and storing container, and Fig. 1B, showing a front
view of the
same, in accordance with some embodiments of the disclosure.
[0053] Fig. 1A shows a container 100, which may be made of any sturdy
material,
such as metal, plastic, or the like. Container 100 may have an inner container
104,
insulated from container 100 by insulation layer 106 made of any insulation
material,
such as fiberglass (specifically glass wool), cellulose, rock wool,
polystyrene foam,
urethane foam, vermiculite, perlite, cork, or others. In some embodiments, the
external
radius of the container may be several decimeters, for example between 50 and
150 cm,
and the internal radios may be smaller in 5-20 cm, for example 10 cm, thus
providing
for 10cm of insulation.
[0054] Within container 104 are tubes 108 through which a refrigerant fluid
may be
streamed to and from cooling unit 114. Cooling unit 114 may comprise cooling
element
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116, which may have attached thereto on either side, directly or indirectly, a
thin
electrically resistant layer 112. Layer 112 may have thereon electrically
conductive
coating and electrical wires. In some embodiments, layer 112 may be
strengthened by a
thermal insulating frame.
[0055] The system may further comprise a feedback mechanism or a sensor for
estimating the amount of ice formed on layer 112, or whether a sufficient
amount has
been formed within the container. The system may also comprise a controllable
switch
(not shown), for closing a circuit such that current is applied to the
electrical wires
when it is determined that a sufficient amount of ice has been formed on the
layer and
io should be released. When applying current, the refrigeration may be
stopped, for
enhancing the ice release process and saving energy.
[0056] It will be appreciated that a cooling system may comprise additional
components positioned externally or internally to container 100, such as a
compressor,
condenser, metering device, or the like.
[0057] Referring now to Fig. 2A, showing a more detailed view of an embodiment
of
cooling unit 114, in accordance with some embodiments of the disclosure.
[0058] Cooling unit 114 may comprise cooling element 116, heat spreading
plates
204, and layer 112.
[0059] Cooling element 116 may be formed as a spiral tube as shown in Fig. 2A,
flattened tube, or the like. In further embodiments cooling element 116 may
comprise
two metal plates made for example from aluminum, copper, or the like, that are
rolled-
bonded together with the refrigerant channels embedded between, or the like.
The spiral
tube shown on Fig. 2A may comprise straight parts 202 and bends 203.
[0060] Cooling unit 114 may also comprise one or more heat spreading plates
204,
designed to correspond to and be attached to cooling element 116 along
straight parts
202. Plates 204 may therefore reduce the contact area of cooling element 116
with the
water, and thus the amount of ice formed thereon, which ice is hard to
release.
However, plates 204 may transfer the heat from the water to the cooling
element,
thereby transferring cold from cooling element 116 to the water. Heat
spreading plates
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204 may be of any heat conductive material, such as aluminum, copper, any
other
metal, or the like.
[0061] Fig. 2B shows a top view of the cooling unit, including cooling element
116,
heat spreading plates 204 and layers 112.
[0062] Fig. 2C shows an exemplary embodiment of heat spreading plate 204 and
layers 112. Heat spreading plate 204 has thereon grooves 206 corresponding to
straight
parts 202 of cooling element 116 which is formed as a spiral tube.
[0063] Layer 112 may be made of a thin electrically resistant polyimide film,
such as
a film of Kapton 0. The film may be made of Kapton 0 RS, which has thereon
io electrically conducive coating. Layers 112 may be positioned such that
the coating is on
the side of the film far from heat spreading plate 204. Kapton 0 RS may have
surface
electrical resistivity of 100 ohms/sq. and Tensile Strength larger than 100
MPa. Kapton
0 RS may be resilient to high range of temperatures. The thickness of layer
112 may
be, for example, 50 m. Thus, layer 112 does not thermally insulate between
heat
is spreading plate 204 and the water.
[0064] In other embodiments, layer 112 may be made of Silicone Rubber or PET
plastic. However, Kapton RS offers higher electrical resistance, thin gauge
and
mechanical properties.
[0065] While heat spreading plate 204 may generally correspond in size to the
parts of
20 cooling element 116 which it is attached to, layer 112 may be larger,
for example
between two millimeters and ten centimeters on either side of either
dimension. This
enables a significant volume of ice to be formed on layer 112 on the area
corresponding
to heat spreading plate 204, without connecting to the ice formed on the areas
of
cooling element 116 which are in direct contact with water.
25 [0066] Fig. 2D shows layer 112, with electrical wires 208 and 218
attached thereto on
opposite ends of its coated side. Due to the electrical conductivity of the
coating of
layer 112, once current is supplied to wires 208 and 218, layer 112 heats, and
the ice
formed on it releases.
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[0067] Fig. 3A shows a perspective view of layer 112 with electrical wires
208, 218
and ice cap 304 formed on layer 112 in the areas at which heat spreading plate
204 is in
touch with layer 112.
[0068] Fig. 3B is a top view of the cooling unit, with cooling element 116,
heat
spreading plates 204, layers 112 and ice caps 304 formed on either layer 112.
[0069] It will be appreciated that Figs. 3A and 3B are illustrative, and the
ice may be
formed on layers 112 and melted in different shapes when current is supplied
to
electrical wires 208, 218. However, as layers 112 are heated throughout, and
due to the
size of layers 112 exceeding the projection of cooling element 116, the ice
releases and
io does not stick to any point or area of cooling unit 116 or hook to the
cooling unit 116.
[0070] It will be appreciated that the layers 112 do not have to be heated at
once.
However, once any layer 112 is heated, cooling element 116 may not be cooled,
in
order to save energy. Thus, heating layers 112 at different times causes
longer pauses in
the ice generation process, therefore in some embodiments layers 112 may be
heated
concurrently.
[0071] Referring now to Fig. 4, showing a flowchart of a steps in a method for
creating and storing cold, in accordance with some embodiments of the
disclosure.
[0072] On step 400, a cooling unit may be activated, for example by streaming
refrigerant through a cooling element.
[0073] On step 404, which may be performed in an ongoing manner, it may be
determined whether a predetermined amount of ice has been created. This check
may be
performed using any method or any sensor for capturing at least one aspect of
the
formed ice. In one embodiment, the temperature of the fluid flowing back from
the
cooling unit may be measured. A temperature below a predetermined value may
indicate that at least a sufficient amount of ice has been formed on the
cooling unit or
members thereof. In other embodiments, the size of the ice block formed on the
layers
may be determined by analyzing images captured by an image capturing device,
or the
like.
[0074] It will be appreciated that a cooling system in accordance with the
disclosure
may further comprise a controllable switch, for closing a circuit such that
current is
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applied to the electrical wiring when it is determined that a sufficient
amount of ice has
been formed on the layer and should be released. The current may be applied
for a very
short period of time, sufficient for melting enough ice such that the block
may release,
but not more than that. For example, the current may be supplied for a period
such as 10
seconds to five minutes, for example one minute.
[0075] On step 408, if the predetermined amount of ice has been formed, the
cooling
cycle may be stopped and current may be supplied to electrical wires laid on
members
of the cooling unit, such as the electrically resistant layer coated by
thermally
conductive material, such that the Kapton 0 RS layer. The coating is heated,
which
io causes the ice accumulated thereon to release and float towards the top
of the container.
In some embodiments, the heating may start not immediately after cooling has
stopped,
but at a time difference enabling for temperature balancing. If the amount of
ice has not
reached the threshold, execution may continue at step 400 and the cooling
cycle may
continue.
[0076] Once the ice has released, it may be determined on step 412 whether at
least a
predetermined amount of ice has been stored, e.g., whether the amount of ice
that
floated to the top of the container is sufficient, or whether there is room
for more ice in
the container. If the predetermined amount has been stored, the cooling cycle
may stop,
and the ice may be removed or used, at the current time or at a later time. In
some
embodiments, a notification may be provided to a user or operator of the
cooling
system, such as a visual or vocal indication.
[0077] If the amount of stored ice has not reached the predetermined value,
execution
may continue at step 400 and the cooling cycle may continue. The cooling
cycles may
continue as long as the rates are cheap, as long as the green energy is
available, or the
like.
[0078] The formation of an amount for ice that needs to be released, whether
the
amount has indeed been released, and weather a sufficient amount has been
formed
within the container may be determined in a plurality of ways. Some
embodiments
include a visual sensor and a processor for analyzing captured images. Other
embodiments comprise the measurement of the height of the content of water and
ice
within the container. When ice is formed, the water level rises, and when the
ice is
Date Recue/Date Received 2021-02-17
P1216-1 CA
released, its top floats above the water level, therefore the water level
decreases. These
changes can be measured, such that the cooling and heating can alternate as
required.
When the container is full, the ice cannot float, therefore the water level
does not
decrease after a heating cycle. Thus, if after a predetermined time, for
example twice or
5 three times the expected duration of a cooling and heating cycle there is
no change in
the water level, it may be assumed that the container is full of ice. In
further
embodiments, if ice is formed on the cooling element, the temperature of the
refrigerant
going back from the container is lower than after the ice has been released,
therefore the
stages of the process may be determined according to the refrigerant
temperature.
10 [0079] The flowchart Fig. 4 illustrates the functionality and operation
of possible
implementations of systems according to various embodiments of the present
invention.
In this regard, each block in the flowchart may represent a module, segment,
or portion
of instructions, which may comprise one or more executable instructions for
implementing the specified logical function(s). In some alternative
implementations, the
15 functions noted in the block may occur out of the order noted in the
figures. For
example, two blocks shown in succession may, in fact, be executed
substantially
concurrently, or the blocks may sometimes be executed in the reverse order,
depending
upon the functionality involved. It will also be noted that each block of the
flowchart
illustration, and combinations of blocks in the flowchart illustration, can be
implemented by special purpose hardware-based systems such as a controller or
Programmable Logic Controller (PLC) that perform the specified functions or
acts or
carry out combinations of special purpose hardware and computer instructions.
[0080] The descriptions of the various embodiments of the present invention
have
been presented for purposes of illustration, but are not intended to be
exhaustive or
limited to the embodiments disclosed. Many modifications and variations will
be
apparent to those of ordinary skill in the art without departing from the
scope and spirit
of the described embodiments. The terminology used herein was chosen to best
explain
the principles of the embodiments, the practical application or technical
improvement
over technologies found in the marketplace, or to enable others of ordinary
skill in the
art to understand the embodiments disclosed herein.
Date Recue/Date Received 2021-02-17
P1216-1 CA
16
[0081] In the description and claims of the application, each of the words
"comprise"
"include" and "have", and forms thereof, are not necessarily limited to
members in a list
with which the words may be associated.
Date Recue/Date Received 2021-02-17
